ck1 inhibitor d4476 Search Results


93
Tocris ck1 inhibitor d4476
(A and B) Dzip1 interacts with GSK3β. Endogenous GSK3β was immunoprecipitated by Dzip1 but not IgG (A), and endogenous Dzip1 was immunoprecipitated with GFP-GSK3β in HEK 293T cells (B). (C and D) Dzip1 is co-localized with GSK3β at the basal body. G0-phase NIH 3T3 cells expressing GFP-GSK3β were immunostained for Dzip1 and AcTub (C), or cells expressing BFP-Centrin2 were immunostained with GSK3β and Dzip1 (D). Scale bar: 5 μm. (E) GSK3β binds Dzip1 in a kinase-substrate interaction manner. Wild-type (WT) GFP-GSK3β and the mutants S9A, K85R, and R96A were each co-expressed with Myc-Dzip1 in G0-phase HEK 293T cells, and treated with the <t>CK1</t> inhibitor <t>D4476</t> or the CK2 inhibitor CX4945. Note that treatment with CX4945 but not D4476 led to a significant decrease in the extent of the up-shifted Dzip1 bands, although the binding of Dzip1 to the GFP-GSK3β variants showed no difference. The extent of the up-shifting of the Dzip1 bands was decreased in K85R-expressing cells. (F) Phosphorylation of Dzip1 is coordinated with GSK3β activation. The kinase activity of GSK3β was negatively correlated with serum stimulation in NIH 3T3 cells. Note that the up-shifted bands (arrowheads) of Dzip1 became evident after serum depletion for 24–48 h, and disappeared after serum restimulation. γ-Tubulin was set as a loading control. (G) GSK3β phosphorylates Dzip1 in vivo. In resting mouse embryo fibroblast (MEFs) treated versus not treated with GSK3 and CK2 inhibitors, the Dzip1 bands were up-shifted less in GSK3- and CK2-inhibited cells. The protein levels of total β-Catenin and GSK3β were steady, but the phosphorylated (S33/37/T41) β-Catenin specifically disappeared from GSK3-inhibited cells. α-Tubulin was set as a loading control. (H) GSK3β phosphorylates Dzip1 in vitro. Auto-phosphorylation of GSK3β (55 kD), and the phosphorylated bands of the middle (28 kD), C-terminus (36 kD), and N- terminus (50 kD) of Dzip1 are shown (left panel). Coomassie blue staining of the gel shows the loaded amounts of Dzip1 fragments (right panel). Note that the S520A mutation resulted in decreased phosphorylation of Dzip1 by GSK3β. (I) Inhibition of GSK3 by BIO causes loss of phospho-S520 in Dzip1.
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Santa Cruz Biotechnology ck1 inhibitor d4476
Early phosphorylation of p53 in S20 induced by Resv is necessary for p53-stability in MCF-7 R cells. ( A ) MCF-7 R cells were treated with CDDP (6 μM) with or without Resv (100 μM) and ( B ) MCF-7 cells were treated with Resv (100 μM); both cell cultures were treated for 6 h with specific p53-pS20 site kinase inhibitors: <t>CK1</t> (60 μM), CHK2 (25 μM) or AMPK (40 μM). Total and phospho-p53 contents are assessed by Western blot using antibodies directed against total p53 (DO-1) or against the specific phosphorylated residue on S20, as indicated. ( C ) MCF-7 and MCF-7 R cells were treated with a DMSO–ethanol vehicle as control or CDDP (6 μM) with resveratrol (100 μM) and cultured in combination with CK1 (60 μM), CHK2 (25 μM) or AMPK (40 μM) inhibitors for 48 h and were double-stained with Annexin V and propidium iodide (PI) followed by flow cytometry analysis to determine apoptotic cells. The viable cells are located in the lower left quadrant (double negative with Annexin V–/PI–). Apoptotic cells (Annexin V+/PI–) appear in the lower right (early apoptosis) and upper right (late apoptosis) quadrant of data plots. Data are presented as a percentage of the cell population. ( D ) The combined results of three independent cytometry analyses depicting the mean levels of total apoptotic cells are shown. Results are presented as the means ± SD. *** p < 0.001 by one-way ANOVA followed by Turkey’s Multiple Comparison test.
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Cayman Chemical casein kinase 1 (ck1) inhibitor d4476
Early phosphorylation of p53 in S20 induced by Resv is necessary for p53-stability in MCF-7 R cells. ( A ) MCF-7 R cells were treated with CDDP (6 μM) with or without Resv (100 μM) and ( B ) MCF-7 cells were treated with Resv (100 μM); both cell cultures were treated for 6 h with specific p53-pS20 site kinase inhibitors: <t>CK1</t> (60 μM), CHK2 (25 μM) or AMPK (40 μM). Total and phospho-p53 contents are assessed by Western blot using antibodies directed against total p53 (DO-1) or against the specific phosphorylated residue on S20, as indicated. ( C ) MCF-7 and MCF-7 R cells were treated with a DMSO–ethanol vehicle as control or CDDP (6 μM) with resveratrol (100 μM) and cultured in combination with CK1 (60 μM), CHK2 (25 μM) or AMPK (40 μM) inhibitors for 48 h and were double-stained with Annexin V and propidium iodide (PI) followed by flow cytometry analysis to determine apoptotic cells. The viable cells are located in the lower left quadrant (double negative with Annexin V–/PI–). Apoptotic cells (Annexin V+/PI–) appear in the lower right (early apoptosis) and upper right (late apoptosis) quadrant of data plots. Data are presented as a percentage of the cell population. ( D ) The combined results of three independent cytometry analyses depicting the mean levels of total apoptotic cells are shown. Results are presented as the means ± SD. *** p < 0.001 by one-way ANOVA followed by Turkey’s Multiple Comparison test.
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Merck KGaA ck1 inhibitor d4476
( A ) Linear peptide docking sites for enzymes that regulate p53 function. The N-terminus is composed of three transactivation motifs,TAD1, TAD2, and Proline-repeat domain (PRD). A key regulatory domain in the C-terminus (REG) contains the acetylation motifs and phosphorylation site and flanks the Tetramerization domain (TET). The overlapping, but distinct, linear polypeptide docking motifs for p53 regulators include the acetyltransferase p300, the E3 ubiquitin ligase MDM2, iASPP, and the protein kinases including CDK, CK2, <t>CK1,</t> and CHK2 are highlighted. ( B ) Conservation of key phospho-acceptor sites between urochordate and human. The panel highlights the conservation of amino acids and phospho-acceptor sites in the BOX-I transactivation domain of p53 (TAD1 in Figure ) between human and urochordate ( Ciona intestinalis ). The ATM phospho-acceptor site at Ser15 and the Calcium Calmodulin kinase/CK1 phospho-acceptors sites at Thr18 and Ser20 are highlighted as indicated.
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93
Selleck Chemicals ck1 inhibitor d 4476
GSK3β promotes ubiquitination and degradation of Ajuba. A Western blot analysis of HCT116 cells treated with <t>CK1</t> inhibitor D 4476 (50 μM), GSK3β inhibitor CHIR-99021 (50 μM) and S6K1 inhibitor PF-4708671 (50 μM) for 24 h. B HCT116, HT29 and SW480 cells were incubated with GSK3β inhibitor CHIR-99021 (50 μM) for 24 h and collected for western blot. C Western blot analysis for HCT116 cells treated with 50 μM CHIR-99021 at different time points. D HCT116 cells cultured with GSK3β inhibitor CHIR-99021 (50 μM) for 24 h were pretreated with MG132 (20 μM) for 5 h and harvested for IP. E Western blot analysis of HCT116, SW480 and RKO cells transfected with siRNAs targeting GSK3β for 72 h. F Overexpression of Myc-GSK3β and HA-Ajuba to evaluate the expression level of exogenous Ajuba. G HEK293T cells were transfected with increasing amounts of Myc-GSK3β plasmid, followed by western blot analysis. H, I Cells were transfected with the indicated plasmids for 36 h with or without CHIR-99021 (50 μM) for 24 h and exogenous interaction between GSK3β and Ajuba was analyzed with western blot. J, K Upper panel: RKO cells transfected with two GSK3β siRNAs for 72 h were treated with CHX (50 mg/mL) for the indicated times and then were subjected to western blot. Lower panel: Quantification of Ajuba band intensity. L RKO cells were transfected with GSK3β siRNAs and pretreated with MG132 (20 μM) for 5 h. The cell lysates were immunoprecipitated and then subjected to western blot to analyze the ubiquitination level of Ajuba. M GSK3β and β-TrCP siRNAs were either cotransfected or transfected alone into HCT116 cells and the protein level of Ajuba was detected by western blot.
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Merck KGaA chk2 inhibitor
( A ) Linear peptide docking sites for enzymes that regulate p53 function. The N-terminus is composed of three transactivation motifs,TAD1, TAD2, and Proline-repeat domain (PRD). A key regulatory domain in the C-terminus (REG) contains the acetylation motifs and phosphorylation site and flanks the Tetramerization domain (TET). The overlapping, but distinct, linear polypeptide docking motifs for p53 regulators include the acetyltransferase p300, the E3 ubiquitin ligase MDM2, iASPP, and the protein kinases including CDK, CK2, CK1, and <t>CHK2</t> are highlighted. ( B ) Conservation of key phospho-acceptor sites between urochordate and human. The panel highlights the conservation of amino acids and phospho-acceptor sites in the BOX-I transactivation domain of p53 (TAD1 in Figure ) between human and urochordate ( Ciona intestinalis ). The ATM phospho-acceptor site at Ser15 and the Calcium Calmodulin kinase/CK1 phospho-acceptors sites at Thr18 and Ser20 are highlighted as indicated.
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Merck KGaA chk1 inhibitor sb218078
( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A <t>CHK1</t> inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor <t>SB218078</t> (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.
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MetaMorph Inc neurite outgrowth of pc12 cells
( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A <t>CHK1</t> inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor <t>SB218078</t> (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.
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LC Laboratories chemicals immunotechniques im
( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A <t>CHK1</t> inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor <t>SB218078</t> (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.
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ICOS Corporation ck1-specific inhibitors ic261
( A ) Kinase activity in PC12 cells. Equal amounts of protein lysates from PC12 cells either untreated (control) or exposed to NGF for 24 h were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (24 h after NGF stimulation). ( B ) The kinase activity in peak fraction 21 of untreated (control) and NGF stimulated PC12 cells (24 h) was significantly reduced by <t>IC261</t> specifically inhibiting CK1δ and ε in the micromolar range. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting. ( C ) Kinase activity in rat retina. Equal amounts of protein lysates from rat retinal tissue either untreated or treated with ONC+LI were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (ONC+LI). ( D ) The kinase activity in peak fraction 38 of extracts prepared from ONC+LI treated animals was significantly reduced by the CK1δ/ε specific inhibitor IC261. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting.
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Cayman Chemical ikk inhibitor (bay11-7082
( A ) Kinase activity in PC12 cells. Equal amounts of protein lysates from PC12 cells either untreated (control) or exposed to NGF for 24 h were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (24 h after NGF stimulation). ( B ) The kinase activity in peak fraction 21 of untreated (control) and NGF stimulated PC12 cells (24 h) was significantly reduced by <t>IC261</t> specifically inhibiting CK1δ and ε in the micromolar range. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting. ( C ) Kinase activity in rat retina. Equal amounts of protein lysates from rat retinal tissue either untreated or treated with ONC+LI were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (ONC+LI). ( D ) The kinase activity in peak fraction 38 of extracts prepared from ONC+LI treated animals was significantly reduced by the CK1δ/ε specific inhibitor IC261. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting.
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Image Search Results


(A and B) Dzip1 interacts with GSK3β. Endogenous GSK3β was immunoprecipitated by Dzip1 but not IgG (A), and endogenous Dzip1 was immunoprecipitated with GFP-GSK3β in HEK 293T cells (B). (C and D) Dzip1 is co-localized with GSK3β at the basal body. G0-phase NIH 3T3 cells expressing GFP-GSK3β were immunostained for Dzip1 and AcTub (C), or cells expressing BFP-Centrin2 were immunostained with GSK3β and Dzip1 (D). Scale bar: 5 μm. (E) GSK3β binds Dzip1 in a kinase-substrate interaction manner. Wild-type (WT) GFP-GSK3β and the mutants S9A, K85R, and R96A were each co-expressed with Myc-Dzip1 in G0-phase HEK 293T cells, and treated with the CK1 inhibitor D4476 or the CK2 inhibitor CX4945. Note that treatment with CX4945 but not D4476 led to a significant decrease in the extent of the up-shifted Dzip1 bands, although the binding of Dzip1 to the GFP-GSK3β variants showed no difference. The extent of the up-shifting of the Dzip1 bands was decreased in K85R-expressing cells. (F) Phosphorylation of Dzip1 is coordinated with GSK3β activation. The kinase activity of GSK3β was negatively correlated with serum stimulation in NIH 3T3 cells. Note that the up-shifted bands (arrowheads) of Dzip1 became evident after serum depletion for 24–48 h, and disappeared after serum restimulation. γ-Tubulin was set as a loading control. (G) GSK3β phosphorylates Dzip1 in vivo. In resting mouse embryo fibroblast (MEFs) treated versus not treated with GSK3 and CK2 inhibitors, the Dzip1 bands were up-shifted less in GSK3- and CK2-inhibited cells. The protein levels of total β-Catenin and GSK3β were steady, but the phosphorylated (S33/37/T41) β-Catenin specifically disappeared from GSK3-inhibited cells. α-Tubulin was set as a loading control. (H) GSK3β phosphorylates Dzip1 in vitro. Auto-phosphorylation of GSK3β (55 kD), and the phosphorylated bands of the middle (28 kD), C-terminus (36 kD), and N- terminus (50 kD) of Dzip1 are shown (left panel). Coomassie blue staining of the gel shows the loaded amounts of Dzip1 fragments (right panel). Note that the S520A mutation resulted in decreased phosphorylation of Dzip1 by GSK3β. (I) Inhibition of GSK3 by BIO causes loss of phospho-S520 in Dzip1.

Journal: PLoS Biology

Article Title: GSK3β-Dzip1-Rab8 Cascade Regulates Ciliogenesis after Mitosis

doi: 10.1371/journal.pbio.1002129

Figure Lengend Snippet: (A and B) Dzip1 interacts with GSK3β. Endogenous GSK3β was immunoprecipitated by Dzip1 but not IgG (A), and endogenous Dzip1 was immunoprecipitated with GFP-GSK3β in HEK 293T cells (B). (C and D) Dzip1 is co-localized with GSK3β at the basal body. G0-phase NIH 3T3 cells expressing GFP-GSK3β were immunostained for Dzip1 and AcTub (C), or cells expressing BFP-Centrin2 were immunostained with GSK3β and Dzip1 (D). Scale bar: 5 μm. (E) GSK3β binds Dzip1 in a kinase-substrate interaction manner. Wild-type (WT) GFP-GSK3β and the mutants S9A, K85R, and R96A were each co-expressed with Myc-Dzip1 in G0-phase HEK 293T cells, and treated with the CK1 inhibitor D4476 or the CK2 inhibitor CX4945. Note that treatment with CX4945 but not D4476 led to a significant decrease in the extent of the up-shifted Dzip1 bands, although the binding of Dzip1 to the GFP-GSK3β variants showed no difference. The extent of the up-shifting of the Dzip1 bands was decreased in K85R-expressing cells. (F) Phosphorylation of Dzip1 is coordinated with GSK3β activation. The kinase activity of GSK3β was negatively correlated with serum stimulation in NIH 3T3 cells. Note that the up-shifted bands (arrowheads) of Dzip1 became evident after serum depletion for 24–48 h, and disappeared after serum restimulation. γ-Tubulin was set as a loading control. (G) GSK3β phosphorylates Dzip1 in vivo. In resting mouse embryo fibroblast (MEFs) treated versus not treated with GSK3 and CK2 inhibitors, the Dzip1 bands were up-shifted less in GSK3- and CK2-inhibited cells. The protein levels of total β-Catenin and GSK3β were steady, but the phosphorylated (S33/37/T41) β-Catenin specifically disappeared from GSK3-inhibited cells. α-Tubulin was set as a loading control. (H) GSK3β phosphorylates Dzip1 in vitro. Auto-phosphorylation of GSK3β (55 kD), and the phosphorylated bands of the middle (28 kD), C-terminus (36 kD), and N- terminus (50 kD) of Dzip1 are shown (left panel). Coomassie blue staining of the gel shows the loaded amounts of Dzip1 fragments (right panel). Note that the S520A mutation resulted in decreased phosphorylation of Dzip1 by GSK3β. (I) Inhibition of GSK3 by BIO causes loss of phospho-S520 in Dzip1.

Article Snippet: The CK1 inhibitor D4476 (Tocris Bioscience, 2902), rabbit anti-GSK3β (Santa Cruz Biotechnology, sc-9166), β-Catenin (BD, 610154), phosphorylated GSK3β (S9, Cell Signaling Technology, #93365), and phosphorylated β-Catenin (N3, Cell Signaling Technology, #9561) were kind gifts from Dr. Wei Wu (Tsinghua University).

Techniques: Immunoprecipitation, Expressing, Binding Assay, Phospho-proteomics, Activation Assay, Activity Assay, Serum Depletion, Control, In Vivo, In Vitro, Staining, Mutagenesis, Inhibition

Early phosphorylation of p53 in S20 induced by Resv is necessary for p53-stability in MCF-7 R cells. ( A ) MCF-7 R cells were treated with CDDP (6 μM) with or without Resv (100 μM) and ( B ) MCF-7 cells were treated with Resv (100 μM); both cell cultures were treated for 6 h with specific p53-pS20 site kinase inhibitors: CK1 (60 μM), CHK2 (25 μM) or AMPK (40 μM). Total and phospho-p53 contents are assessed by Western blot using antibodies directed against total p53 (DO-1) or against the specific phosphorylated residue on S20, as indicated. ( C ) MCF-7 and MCF-7 R cells were treated with a DMSO–ethanol vehicle as control or CDDP (6 μM) with resveratrol (100 μM) and cultured in combination with CK1 (60 μM), CHK2 (25 μM) or AMPK (40 μM) inhibitors for 48 h and were double-stained with Annexin V and propidium iodide (PI) followed by flow cytometry analysis to determine apoptotic cells. The viable cells are located in the lower left quadrant (double negative with Annexin V–/PI–). Apoptotic cells (Annexin V+/PI–) appear in the lower right (early apoptosis) and upper right (late apoptosis) quadrant of data plots. Data are presented as a percentage of the cell population. ( D ) The combined results of three independent cytometry analyses depicting the mean levels of total apoptotic cells are shown. Results are presented as the means ± SD. *** p < 0.001 by one-way ANOVA followed by Turkey’s Multiple Comparison test.

Journal: Nutrients

Article Title: Induction of p53 Phosphorylation at Serine 20 by Resveratrol Is Required to Activate p53 Target Genes, Restoring Apoptosis in MCF-7 Cells Resistant to Cisplatin

doi: 10.3390/nu10091148

Figure Lengend Snippet: Early phosphorylation of p53 in S20 induced by Resv is necessary for p53-stability in MCF-7 R cells. ( A ) MCF-7 R cells were treated with CDDP (6 μM) with or without Resv (100 μM) and ( B ) MCF-7 cells were treated with Resv (100 μM); both cell cultures were treated for 6 h with specific p53-pS20 site kinase inhibitors: CK1 (60 μM), CHK2 (25 μM) or AMPK (40 μM). Total and phospho-p53 contents are assessed by Western blot using antibodies directed against total p53 (DO-1) or against the specific phosphorylated residue on S20, as indicated. ( C ) MCF-7 and MCF-7 R cells were treated with a DMSO–ethanol vehicle as control or CDDP (6 μM) with resveratrol (100 μM) and cultured in combination with CK1 (60 μM), CHK2 (25 μM) or AMPK (40 μM) inhibitors for 48 h and were double-stained with Annexin V and propidium iodide (PI) followed by flow cytometry analysis to determine apoptotic cells. The viable cells are located in the lower left quadrant (double negative with Annexin V–/PI–). Apoptotic cells (Annexin V+/PI–) appear in the lower right (early apoptosis) and upper right (late apoptosis) quadrant of data plots. Data are presented as a percentage of the cell population. ( D ) The combined results of three independent cytometry analyses depicting the mean levels of total apoptotic cells are shown. Results are presented as the means ± SD. *** p < 0.001 by one-way ANOVA followed by Turkey’s Multiple Comparison test.

Article Snippet: The AMPK inhibitor Compound C (or dorsomorphin), the CK1 inhibitor D4476, the Chk2 inhibitor, anti-rabbit and anti-mouse secondary antibodies, mouse monoclonal anti-phospho-ATM (S1981), rabbit polyclonal anti-ATM, monoclonal anti-p53-HRP (DO-1), and monoclonal anti-BCL-2 were purchased from Santa Cruz Biotechnology (San Diego, CA, USA).

Techniques: Phospho-proteomics, Western Blot, Residue, Control, Cell Culture, Staining, Flow Cytometry, Cytometry, Comparison

In the MCF-7 resistant cell variant (MCF-7 R ), Resv attenuates phosphorylation in S15 and S46 of p53 by dephosphorylation and deactivation of ATM. However, it activates kinases CK1, CHK2, and AMPK to induce phosphorylation of p53 in S20 (which is required to activate p53 in order to upregulate BAX and PUMA genes) and modifies the ratio between BCL-2/BAX expression. The BAX protein was increased while BCL-2 protein was decreased, restoring apoptosis and overcoming chemoresistance. On the other hand, the overexpression of BCL-2 in MCF-7 R cells after CDDP treatment maintains the chemoresistance and blocks apoptosis despite the phosphorylation of p53 in S15 and S46 and the upregulation of NOXA and PUMA .

Journal: Nutrients

Article Title: Induction of p53 Phosphorylation at Serine 20 by Resveratrol Is Required to Activate p53 Target Genes, Restoring Apoptosis in MCF-7 Cells Resistant to Cisplatin

doi: 10.3390/nu10091148

Figure Lengend Snippet: In the MCF-7 resistant cell variant (MCF-7 R ), Resv attenuates phosphorylation in S15 and S46 of p53 by dephosphorylation and deactivation of ATM. However, it activates kinases CK1, CHK2, and AMPK to induce phosphorylation of p53 in S20 (which is required to activate p53 in order to upregulate BAX and PUMA genes) and modifies the ratio between BCL-2/BAX expression. The BAX protein was increased while BCL-2 protein was decreased, restoring apoptosis and overcoming chemoresistance. On the other hand, the overexpression of BCL-2 in MCF-7 R cells after CDDP treatment maintains the chemoresistance and blocks apoptosis despite the phosphorylation of p53 in S15 and S46 and the upregulation of NOXA and PUMA .

Article Snippet: The AMPK inhibitor Compound C (or dorsomorphin), the CK1 inhibitor D4476, the Chk2 inhibitor, anti-rabbit and anti-mouse secondary antibodies, mouse monoclonal anti-phospho-ATM (S1981), rabbit polyclonal anti-ATM, monoclonal anti-p53-HRP (DO-1), and monoclonal anti-BCL-2 were purchased from Santa Cruz Biotechnology (San Diego, CA, USA).

Techniques: Variant Assay, Phospho-proteomics, De-Phosphorylation Assay, Expressing, Over Expression

( A ) Linear peptide docking sites for enzymes that regulate p53 function. The N-terminus is composed of three transactivation motifs,TAD1, TAD2, and Proline-repeat domain (PRD). A key regulatory domain in the C-terminus (REG) contains the acetylation motifs and phosphorylation site and flanks the Tetramerization domain (TET). The overlapping, but distinct, linear polypeptide docking motifs for p53 regulators include the acetyltransferase p300, the E3 ubiquitin ligase MDM2, iASPP, and the protein kinases including CDK, CK2, CK1, and CHK2 are highlighted. ( B ) Conservation of key phospho-acceptor sites between urochordate and human. The panel highlights the conservation of amino acids and phospho-acceptor sites in the BOX-I transactivation domain of p53 (TAD1 in Figure ) between human and urochordate ( Ciona intestinalis ). The ATM phospho-acceptor site at Ser15 and the Calcium Calmodulin kinase/CK1 phospho-acceptors sites at Thr18 and Ser20 are highlighted as indicated.

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: ( A ) Linear peptide docking sites for enzymes that regulate p53 function. The N-terminus is composed of three transactivation motifs,TAD1, TAD2, and Proline-repeat domain (PRD). A key regulatory domain in the C-terminus (REG) contains the acetylation motifs and phosphorylation site and flanks the Tetramerization domain (TET). The overlapping, but distinct, linear polypeptide docking motifs for p53 regulators include the acetyltransferase p300, the E3 ubiquitin ligase MDM2, iASPP, and the protein kinases including CDK, CK2, CK1, and CHK2 are highlighted. ( B ) Conservation of key phospho-acceptor sites between urochordate and human. The panel highlights the conservation of amino acids and phospho-acceptor sites in the BOX-I transactivation domain of p53 (TAD1 in Figure ) between human and urochordate ( Ciona intestinalis ). The ATM phospho-acceptor site at Ser15 and the Calcium Calmodulin kinase/CK1 phospho-acceptors sites at Thr18 and Ser20 are highlighted as indicated.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Phospho-proteomics, Ubiquitin Proteomics

p53 is activated by distinct stresses, some of which include as indicated, ionising radiation, viral infection, metabolic stress induced by an altered AMP/ATP ratio, and oncogene activation. The X-ray-induced Ser20 site kinase is ATM-dependent, but its identity is unknown (highlighted by

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: p53 is activated by distinct stresses, some of which include as indicated, ionising radiation, viral infection, metabolic stress induced by an altered AMP/ATP ratio, and oncogene activation. The X-ray-induced Ser20 site kinase is ATM-dependent, but its identity is unknown (highlighted by "?"). CK1 is the DNA virus HHV-6B-induced p53 Ser20 kinase, but the upstream sensor is currently undefined (highlighted by "?"). The Ser20 site kinase induced by an elevated AMP/ATP ratio is AMPK, and LKB is the likely upstream sensor. DAPK-1 is the p53 Ser20 kinase induced by inappropriate oncogene activation, and ERK or ARF are the likely upstream sensors. These data support the formation of a model suggesting that the phosphorylation of p53 at Ser20 is triggered by distinct stress-responsive signaling cascades. Future analysis will be required to determine the identity of all the enzymes that mediate stress-induced phosphorylation at this site and "integrate" the p53 response and developing disease models that deregulate these signaling cascades.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Infection, Activation Assay, Virus, Phospho-proteomics

( A ) A CK1 inhibitor attenuates Ser20 site phosphorylation of p53 and p53 induction mediated by HHV-6B infection. MOLT-3 cells were infected with (even-numbered lanes) or without (odd-numbered lanes) HHV-6B for 48 hours in the presence of increasing concentrations (10-100μM) of the CK1 inhibitor D4476 (lanes 3-14) or a DMSO solvent control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( B ) A CK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (10-60μM) of the CK1 inhibitor D4476 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: ( A ) A CK1 inhibitor attenuates Ser20 site phosphorylation of p53 and p53 induction mediated by HHV-6B infection. MOLT-3 cells were infected with (even-numbered lanes) or without (odd-numbered lanes) HHV-6B for 48 hours in the presence of increasing concentrations (10-100μM) of the CK1 inhibitor D4476 (lanes 3-14) or a DMSO solvent control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( B ) A CK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (10-60μM) of the CK1 inhibitor D4476 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Phospho-proteomics, Infection, Solvent, Control, Western Blot, Cell Culture

( A ) An AMPK inhibitor attenuates Ser20 site phosphorylation of p53 and p53 induction mediated by treatment with AICAR. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 0.5mM AICAR for 24 hours after an initial 24-hour pre-treatment with: increasing concentrations (2.5-20μM) of the AMPK inhibitor Compound C (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( B ) An AMPK inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1.25-10μM) of the AMPK inhibitor Compound C (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C ) A CK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with AICAR. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 0.5mM AICAR for 24 hours after an initial 24-hour pre-treatment with: increasing concentrations (10-60μM) of the CK1 inhibitor D4476 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( D ) An ATM inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with AICAR. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 0.5mM AICAR for 24 hours after an initial 24-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: ( A ) An AMPK inhibitor attenuates Ser20 site phosphorylation of p53 and p53 induction mediated by treatment with AICAR. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 0.5mM AICAR for 24 hours after an initial 24-hour pre-treatment with: increasing concentrations (2.5-20μM) of the AMPK inhibitor Compound C (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( B ) An AMPK inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1.25-10μM) of the AMPK inhibitor Compound C (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C ) A CK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with AICAR. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 0.5mM AICAR for 24 hours after an initial 24-hour pre-treatment with: increasing concentrations (10-60μM) of the CK1 inhibitor D4476 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( D ) An ATM inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with AICAR. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 0.5mM AICAR for 24 hours after an initial 24-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Phospho-proteomics, Solvent, Control, Western Blot, Cell Culture

GSK3β promotes ubiquitination and degradation of Ajuba. A Western blot analysis of HCT116 cells treated with CK1 inhibitor D 4476 (50 μM), GSK3β inhibitor CHIR-99021 (50 μM) and S6K1 inhibitor PF-4708671 (50 μM) for 24 h. B HCT116, HT29 and SW480 cells were incubated with GSK3β inhibitor CHIR-99021 (50 μM) for 24 h and collected for western blot. C Western blot analysis for HCT116 cells treated with 50 μM CHIR-99021 at different time points. D HCT116 cells cultured with GSK3β inhibitor CHIR-99021 (50 μM) for 24 h were pretreated with MG132 (20 μM) for 5 h and harvested for IP. E Western blot analysis of HCT116, SW480 and RKO cells transfected with siRNAs targeting GSK3β for 72 h. F Overexpression of Myc-GSK3β and HA-Ajuba to evaluate the expression level of exogenous Ajuba. G HEK293T cells were transfected with increasing amounts of Myc-GSK3β plasmid, followed by western blot analysis. H, I Cells were transfected with the indicated plasmids for 36 h with or without CHIR-99021 (50 μM) for 24 h and exogenous interaction between GSK3β and Ajuba was analyzed with western blot. J, K Upper panel: RKO cells transfected with two GSK3β siRNAs for 72 h were treated with CHX (50 mg/mL) for the indicated times and then were subjected to western blot. Lower panel: Quantification of Ajuba band intensity. L RKO cells were transfected with GSK3β siRNAs and pretreated with MG132 (20 μM) for 5 h. The cell lysates were immunoprecipitated and then subjected to western blot to analyze the ubiquitination level of Ajuba. M GSK3β and β-TrCP siRNAs were either cotransfected or transfected alone into HCT116 cells and the protein level of Ajuba was detected by western blot.

Journal: Neoplasia (New York, N.Y.)

Article Title: SCF β-TrCP targets Ajuba for degradation in a GSK3β-dependent manner in colorectal cancer

doi: 10.1016/j.neo.2025.101175

Figure Lengend Snippet: GSK3β promotes ubiquitination and degradation of Ajuba. A Western blot analysis of HCT116 cells treated with CK1 inhibitor D 4476 (50 μM), GSK3β inhibitor CHIR-99021 (50 μM) and S6K1 inhibitor PF-4708671 (50 μM) for 24 h. B HCT116, HT29 and SW480 cells were incubated with GSK3β inhibitor CHIR-99021 (50 μM) for 24 h and collected for western blot. C Western blot analysis for HCT116 cells treated with 50 μM CHIR-99021 at different time points. D HCT116 cells cultured with GSK3β inhibitor CHIR-99021 (50 μM) for 24 h were pretreated with MG132 (20 μM) for 5 h and harvested for IP. E Western blot analysis of HCT116, SW480 and RKO cells transfected with siRNAs targeting GSK3β for 72 h. F Overexpression of Myc-GSK3β and HA-Ajuba to evaluate the expression level of exogenous Ajuba. G HEK293T cells were transfected with increasing amounts of Myc-GSK3β plasmid, followed by western blot analysis. H, I Cells were transfected with the indicated plasmids for 36 h with or without CHIR-99021 (50 μM) for 24 h and exogenous interaction between GSK3β and Ajuba was analyzed with western blot. J, K Upper panel: RKO cells transfected with two GSK3β siRNAs for 72 h were treated with CHX (50 mg/mL) for the indicated times and then were subjected to western blot. Lower panel: Quantification of Ajuba band intensity. L RKO cells were transfected with GSK3β siRNAs and pretreated with MG132 (20 μM) for 5 h. The cell lysates were immunoprecipitated and then subjected to western blot to analyze the ubiquitination level of Ajuba. M GSK3β and β-TrCP siRNAs were either cotransfected or transfected alone into HCT116 cells and the protein level of Ajuba was detected by western blot.

Article Snippet: CK1 inhibitor D 4476 (S7642), GSK3β inhibitor CHIR-99021 (S1263) and S6K1 inhibitor PF-4708671 (S2163) were purchased from Selleck.

Techniques: Ubiquitin Proteomics, Western Blot, Incubation, Cell Culture, Transfection, Over Expression, Expressing, Plasmid Preparation, Immunoprecipitation

( A ) Linear peptide docking sites for enzymes that regulate p53 function. The N-terminus is composed of three transactivation motifs,TAD1, TAD2, and Proline-repeat domain (PRD). A key regulatory domain in the C-terminus (REG) contains the acetylation motifs and phosphorylation site and flanks the Tetramerization domain (TET). The overlapping, but distinct, linear polypeptide docking motifs for p53 regulators include the acetyltransferase p300, the E3 ubiquitin ligase MDM2, iASPP, and the protein kinases including CDK, CK2, CK1, and CHK2 are highlighted. ( B ) Conservation of key phospho-acceptor sites between urochordate and human. The panel highlights the conservation of amino acids and phospho-acceptor sites in the BOX-I transactivation domain of p53 (TAD1 in Figure ) between human and urochordate ( Ciona intestinalis ). The ATM phospho-acceptor site at Ser15 and the Calcium Calmodulin kinase/CK1 phospho-acceptors sites at Thr18 and Ser20 are highlighted as indicated.

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: ( A ) Linear peptide docking sites for enzymes that regulate p53 function. The N-terminus is composed of three transactivation motifs,TAD1, TAD2, and Proline-repeat domain (PRD). A key regulatory domain in the C-terminus (REG) contains the acetylation motifs and phosphorylation site and flanks the Tetramerization domain (TET). The overlapping, but distinct, linear polypeptide docking motifs for p53 regulators include the acetyltransferase p300, the E3 ubiquitin ligase MDM2, iASPP, and the protein kinases including CDK, CK2, CK1, and CHK2 are highlighted. ( B ) Conservation of key phospho-acceptor sites between urochordate and human. The panel highlights the conservation of amino acids and phospho-acceptor sites in the BOX-I transactivation domain of p53 (TAD1 in Figure ) between human and urochordate ( Ciona intestinalis ). The ATM phospho-acceptor site at Ser15 and the Calcium Calmodulin kinase/CK1 phospho-acceptors sites at Thr18 and Ser20 are highlighted as indicated.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Phospho-proteomics, Ubiquitin Proteomics

( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A CHK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor SB218078 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: ( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A CHK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor SB218078 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Phospho-proteomics, Cell Culture, Solvent, Control, Western Blot

( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A CHK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor SB218078 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Journal: Aging

Article Title: The regulation of p53 by phosphorylation: a model for how distinct signals integrate into the p53 pathway

doi:

Figure Lengend Snippet: ( A, B ) A CHK2 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( A ) or 10-100μM ( B )] of the CHK2 inhibitor (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( C, D ) A CHK1 inhibitor does not attenuate Ser20 site phosphorylation of p53 nor p53 induction mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations [1-10μM ( C ) or 5-50μM ( D )] of the CHK1 inhibitor SB218078 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins. ( E ) An ATM inhibitor attenuates Ser20 site phosphorylation of p53, but not p53 induction, mediated by treatment with X-rays. MOLT-3 cells were treated with (even-numbered lanes) or without (odd-numbered lanes) 6Gy X-ray and cultured for 4 hours after an initial 44-hour pre-treatment with: increasing concentrations (1-10μM) of the ATM inhibitor KU-55933 (lanes 5-12), a DMSO solvent control (lanes 3-4), or a culture medium control (lanes 1-2). Cell lysates were examined by Western blotting with antibodies against the indicated proteins.

Article Snippet: The AMPK inhibitor Compound C (or Dorsomorphin), the CHK1 inhibitor SB218078, the CHK2 inhibitor, and the CK1 inhibitor D4476 were purchased from Merck Chemicals (Nottingham, UK).

Techniques: Phospho-proteomics, Cell Culture, Solvent, Control, Western Blot

( A ) Kinase activity in PC12 cells. Equal amounts of protein lysates from PC12 cells either untreated (control) or exposed to NGF for 24 h were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (24 h after NGF stimulation). ( B ) The kinase activity in peak fraction 21 of untreated (control) and NGF stimulated PC12 cells (24 h) was significantly reduced by IC261 specifically inhibiting CK1δ and ε in the micromolar range. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting. ( C ) Kinase activity in rat retina. Equal amounts of protein lysates from rat retinal tissue either untreated or treated with ONC+LI were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (ONC+LI). ( D ) The kinase activity in peak fraction 38 of extracts prepared from ONC+LI treated animals was significantly reduced by the CK1δ/ε specific inhibitor IC261. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting.

Journal: PLoS ONE

Article Title: Neurite Outgrowth of Mature Retinal Ganglion Cells and PC12 Cells Requires Activity of CK1δ and CK1ε

doi: 10.1371/journal.pone.0020857

Figure Lengend Snippet: ( A ) Kinase activity in PC12 cells. Equal amounts of protein lysates from PC12 cells either untreated (control) or exposed to NGF for 24 h were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (24 h after NGF stimulation). ( B ) The kinase activity in peak fraction 21 of untreated (control) and NGF stimulated PC12 cells (24 h) was significantly reduced by IC261 specifically inhibiting CK1δ and ε in the micromolar range. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting. ( C ) Kinase activity in rat retina. Equal amounts of protein lysates from rat retinal tissue either untreated or treated with ONC+LI were loaded onto a 1 ml Resource-Q column for ion exchange chromatography and eluted with a linear gradient of increasing NaCl concentration (represented as a solid diagonal line). Fractions were collected and the CK1δ/ε specific kinase activity was determined in each single fraction as described in detail in Material and Methods. Kinase activities (CPM: counts per minute) are represented by open squares (control) or closed triangles (ONC+LI). ( D ) The kinase activity in peak fraction 38 of extracts prepared from ONC+LI treated animals was significantly reduced by the CK1δ/ε specific inhibitor IC261. Phosphate incorporation into GST-p53 1–64 (FP267) was quantified by Cherenkov counting.

Article Snippet: After 30 min, medium was exchanged to growth medium containing the CK1-specific inhibitors IC261 (ICOS Corporation, Bothell, USA) or D4476 (Calbiochem, Darmstadt, Germany) or DMSO/transfection reagent (as a negative control).

Techniques: Activity Assay, Control, Ion Exchange Chromatography, Concentration Assay

( A ) PC12 cells were cultured for 3 days without NGF (control) and in the presence of NGF+vehicle or NGF+CKI-7 (50 and 200 µM) or IC261 (0.5, 1.5 and 50 µM). In a concentration dependent manner the average neurite length of NGF stimulated PC12 cells was markedly reduced in the presence of the CK1-specific inhibitors CKI-7 or IC261. Treatment effects: **p<0.01 and ***p<0.001 compared to cells exposed to NGF+vehicle. ( B, C ) LI stimulated RGCs were cultured in the absence (control) or presence of CKI-7 (B; 50, 200 and 800 µM) or IC261 (C; 0.5, 1.5 and 50 µM). Neurite outgrowth was compromised in a concentration dependent manner. The survival of RGCs was only affected in the presence of CKI-7 at 800 µM. Treatment effects compared to control groups: *p<0.05, **p<0.01, ***p<0.001.

Journal: PLoS ONE

Article Title: Neurite Outgrowth of Mature Retinal Ganglion Cells and PC12 Cells Requires Activity of CK1δ and CK1ε

doi: 10.1371/journal.pone.0020857

Figure Lengend Snippet: ( A ) PC12 cells were cultured for 3 days without NGF (control) and in the presence of NGF+vehicle or NGF+CKI-7 (50 and 200 µM) or IC261 (0.5, 1.5 and 50 µM). In a concentration dependent manner the average neurite length of NGF stimulated PC12 cells was markedly reduced in the presence of the CK1-specific inhibitors CKI-7 or IC261. Treatment effects: **p<0.01 and ***p<0.001 compared to cells exposed to NGF+vehicle. ( B, C ) LI stimulated RGCs were cultured in the absence (control) or presence of CKI-7 (B; 50, 200 and 800 µM) or IC261 (C; 0.5, 1.5 and 50 µM). Neurite outgrowth was compromised in a concentration dependent manner. The survival of RGCs was only affected in the presence of CKI-7 at 800 µM. Treatment effects compared to control groups: *p<0.05, **p<0.01, ***p<0.001.

Article Snippet: After 30 min, medium was exchanged to growth medium containing the CK1-specific inhibitors IC261 (ICOS Corporation, Bothell, USA) or D4476 (Calbiochem, Darmstadt, Germany) or DMSO/transfection reagent (as a negative control).

Techniques: Cell Culture, Control, Concentration Assay

( A ) LI stimulated RGCs were cultured for 24 h and then exposed to vehicle or different concentrations of the CK1-specific inhibitors IC261 (0.5, 1.5 and 50 µM) or CKI-7 (50 and 200 µM). The average neurite length of RGCs was determined after 24 h (first control) and 48 h, respectively. Treatment effects: ***p<0.001. ( B ) The number of RGCs per well in all groups was not affected by any treatment described in (A). ( C ) LI stimulated RGCs were cultured for 48 h and subsequently monitored in a flow-through chamber for live cell imaging. In the presence of vehicle or inhibitors IC261 (50 µM) or D4476 (5 µM) cells were recorded for 4 h. Retraction of the outgrown neurite after exposure to IC261 and D4476 is shown at 0, 120 and 240 min. Arrowheads indicate the position of the cell body, arrows the position of the growth cone. Scale bar: 50 µm. ( D ) Quantification of neurite retraction of RGCs over time exposed to vehicle (control, closed squares) or inhibitors IC261 (50 µM, open triangles) or D4476 (5 µM, open squares) specifically inhibiting CK1δ and ε.

Journal: PLoS ONE

Article Title: Neurite Outgrowth of Mature Retinal Ganglion Cells and PC12 Cells Requires Activity of CK1δ and CK1ε

doi: 10.1371/journal.pone.0020857

Figure Lengend Snippet: ( A ) LI stimulated RGCs were cultured for 24 h and then exposed to vehicle or different concentrations of the CK1-specific inhibitors IC261 (0.5, 1.5 and 50 µM) or CKI-7 (50 and 200 µM). The average neurite length of RGCs was determined after 24 h (first control) and 48 h, respectively. Treatment effects: ***p<0.001. ( B ) The number of RGCs per well in all groups was not affected by any treatment described in (A). ( C ) LI stimulated RGCs were cultured for 48 h and subsequently monitored in a flow-through chamber for live cell imaging. In the presence of vehicle or inhibitors IC261 (50 µM) or D4476 (5 µM) cells were recorded for 4 h. Retraction of the outgrown neurite after exposure to IC261 and D4476 is shown at 0, 120 and 240 min. Arrowheads indicate the position of the cell body, arrows the position of the growth cone. Scale bar: 50 µm. ( D ) Quantification of neurite retraction of RGCs over time exposed to vehicle (control, closed squares) or inhibitors IC261 (50 µM, open triangles) or D4476 (5 µM, open squares) specifically inhibiting CK1δ and ε.

Article Snippet: After 30 min, medium was exchanged to growth medium containing the CK1-specific inhibitors IC261 (ICOS Corporation, Bothell, USA) or D4476 (Calbiochem, Darmstadt, Germany) or DMSO/transfection reagent (as a negative control).

Techniques: Cell Culture, Control, Live Cell Imaging