recombinant flag- ikkε Search Results


95
Selleck Chemicals inhibitors
(A) HEK293 cells were transiently transfected with a His-3xFLAG-FAT10 (FLAG-FAT10) expression construct and stimulated for 24 h with TNF. Lysates were subjected to immunoprecipitation using FLAG-reactive antibodies, coupled to sepharose beads, and subsequently analyzed by Phos-tag/SDS–PAGE/IB analysis. Where indicated, cells were pretreated before TNF stimulation with the displayed <t>inhibitors</t> for a total of 3 h (10 µM each). (B) HEK293 cells were transiently transfected with expression plasmids for the different kinases. Cells were harvested, lysed, and subjected to immunoprecipitation using anti-FLAG or anti-HA antibodies, coupled to sepharose beads. Subsequently, the immunoprecipitated kinases were incubated with recombinant FAT10 (rFAT10) and an in vitro reaction was performed in the kinase buffer. The phosphorylation status of FAT10 was analyzed by Phos-tag/SDS–PAGE and IB. Asterisks mark unspecific background bands. (C) FLAG-FAT10 and the indicated kinases were transiently overexpressed in HEK293 cells followed by TNF stimulation. After 24 h, cells were lysed and subjected to immunoprecipitation against the FLAG-tag, combined with Phos-tag/SDS–PAGE and IB analysis. (D) Recombinant FAT10 (rFAT10) was incubated with recombinant kinases IKKβ, IKKε or MK3 for 45 min at 30°C. Subsequently, proteins were separated on a Phos-tag/SDS–PAGE followed by immunoblot analysis using the antibodies indicated. (E) HEK293 cells were prepared as described in (A). Where specified, cells were pretreated with the inhibitors indicated (10 µM each) for a total of 3 h before stimulation with TNF. One representative example out of three independent experiments with the same outcomes is shown. Source data are available for this figure.
Inhibitors, supplied by Selleck Chemicals, used in various techniques. Bioz Stars score: 95/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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Average 95 stars, based on 1 article reviews
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90
Active Motif recombinant flag- ikkε #31177
(A) HEK293 cells were transiently transfected with a His-3xFLAG-FAT10 (FLAG-FAT10) expression construct and stimulated for 24 h with TNF. Lysates were subjected to immunoprecipitation using FLAG-reactive antibodies, coupled to sepharose beads, and subsequently analyzed by Phos-tag/SDS–PAGE/IB analysis. Where indicated, cells were pretreated before TNF stimulation with the displayed <t>inhibitors</t> for a total of 3 h (10 µM each). (B) HEK293 cells were transiently transfected with expression plasmids for the different kinases. Cells were harvested, lysed, and subjected to immunoprecipitation using anti-FLAG or anti-HA antibodies, coupled to sepharose beads. Subsequently, the immunoprecipitated kinases were incubated with recombinant FAT10 (rFAT10) and an in vitro reaction was performed in the kinase buffer. The phosphorylation status of FAT10 was analyzed by Phos-tag/SDS–PAGE and IB. Asterisks mark unspecific background bands. (C) FLAG-FAT10 and the indicated kinases were transiently overexpressed in HEK293 cells followed by TNF stimulation. After 24 h, cells were lysed and subjected to immunoprecipitation against the FLAG-tag, combined with Phos-tag/SDS–PAGE and IB analysis. (D) Recombinant FAT10 (rFAT10) was incubated with recombinant kinases IKKβ, IKKε or MK3 for 45 min at 30°C. Subsequently, proteins were separated on a Phos-tag/SDS–PAGE followed by immunoblot analysis using the antibodies indicated. (E) HEK293 cells were prepared as described in (A). Where specified, cells were pretreated with the inhibitors indicated (10 µM each) for a total of 3 h before stimulation with TNF. One representative example out of three independent experiments with the same outcomes is shown. Source data are available for this figure.
Recombinant Flag Ikkε #31177, supplied by Active Motif, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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Average 90 stars, based on 1 article reviews
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95
Santa Cruz Biotechnology sc
(A) HEK293 cells were transiently transfected with a His-3xFLAG-FAT10 (FLAG-FAT10) expression construct and stimulated for 24 h with TNF. Lysates were subjected to immunoprecipitation using FLAG-reactive antibodies, coupled to sepharose beads, and subsequently analyzed by Phos-tag/SDS–PAGE/IB analysis. Where indicated, cells were pretreated before TNF stimulation with the displayed <t>inhibitors</t> for a total of 3 h (10 µM each). (B) HEK293 cells were transiently transfected with expression plasmids for the different kinases. Cells were harvested, lysed, and subjected to immunoprecipitation using anti-FLAG or anti-HA antibodies, coupled to sepharose beads. Subsequently, the immunoprecipitated kinases were incubated with recombinant FAT10 (rFAT10) and an in vitro reaction was performed in the kinase buffer. The phosphorylation status of FAT10 was analyzed by Phos-tag/SDS–PAGE and IB. Asterisks mark unspecific background bands. (C) FLAG-FAT10 and the indicated kinases were transiently overexpressed in HEK293 cells followed by TNF stimulation. After 24 h, cells were lysed and subjected to immunoprecipitation against the FLAG-tag, combined with Phos-tag/SDS–PAGE and IB analysis. (D) Recombinant FAT10 (rFAT10) was incubated with recombinant kinases IKKβ, IKKε or MK3 for 45 min at 30°C. Subsequently, proteins were separated on a Phos-tag/SDS–PAGE followed by immunoblot analysis using the antibodies indicated. (E) HEK293 cells were prepared as described in (A). Where specified, cells were pretreated with the inhibitors indicated (10 µM each) for a total of 3 h before stimulation with TNF. One representative example out of three independent experiments with the same outcomes is shown. Source data are available for this figure.
Sc, supplied by Santa Cruz Biotechnology, used in various techniques. Bioz Stars score: 95/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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92
Santa Cruz Biotechnology rabbit antibodies against ikkα
(A) Tax activates <t>IKK</t> in a cell-free system. Cell extracts (S100) of Jurkat T or NEMO-deficient Jurkat T cells were incubated with Tax WT or M22 (100 nM each), and ATP for 1 h at 30°C. Recombinant NEMO (100 nM) was added into the NEMO-deficient extracts to restore IKK activation. IKK activation was detected by phosphorylation of IKKα, IKKβ and its substrate IκBα. (B) Tax activates NF-κB in cells. 293T cells in 12-well-plates were transfected with 1, 10 or 100 ng of plasmids encoding Tax WT or M22, together with a NF-κB firefly-luciferase reporter and a renilla-luciferase reporter (internal control). The firefly-luciferase activity was measured 24 h later and normalized by renilla-luciferase. Tax protein expression was detected by immunoblotting with an anti-Tax antibody. FH: FLAG-10xHis tag.
Rabbit Antibodies Against Ikkα, supplied by Santa Cruz Biotechnology, used in various techniques. Bioz Stars score: 92/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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92
Addgene inc kinaseinactive ikkε k38a
Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with <t>IKKε.</t> A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.
Kinaseinactive Ikkε K38a, supplied by Addgene inc, used in various techniques. Bioz Stars score: 92/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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92
Addgene inc ikkα
Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with <t>IKKε.</t> A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.
Ikkα, supplied by Addgene inc, used in various techniques. Bioz Stars score: 92/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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90
Tularik Inc recombinant flag-ikk α
Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with <t>IKKε.</t> A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.
Recombinant Flag Ikk α, supplied by Tularik Inc, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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90
Active Motif recombinant flag-ikkε
Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with <t>IKKε.</t> A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.
Recombinant Flag Ikkε, supplied by Active Motif, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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96
Proteintech ikk γ
Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with <t>IKKε.</t> A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.
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93
Addgene inc human flag ikkε
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Human Flag Ikkε, supplied by Addgene inc, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
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(A) HEK293 cells were transiently transfected with a His-3xFLAG-FAT10 (FLAG-FAT10) expression construct and stimulated for 24 h with TNF. Lysates were subjected to immunoprecipitation using FLAG-reactive antibodies, coupled to sepharose beads, and subsequently analyzed by Phos-tag/SDS–PAGE/IB analysis. Where indicated, cells were pretreated before TNF stimulation with the displayed inhibitors for a total of 3 h (10 µM each). (B) HEK293 cells were transiently transfected with expression plasmids for the different kinases. Cells were harvested, lysed, and subjected to immunoprecipitation using anti-FLAG or anti-HA antibodies, coupled to sepharose beads. Subsequently, the immunoprecipitated kinases were incubated with recombinant FAT10 (rFAT10) and an in vitro reaction was performed in the kinase buffer. The phosphorylation status of FAT10 was analyzed by Phos-tag/SDS–PAGE and IB. Asterisks mark unspecific background bands. (C) FLAG-FAT10 and the indicated kinases were transiently overexpressed in HEK293 cells followed by TNF stimulation. After 24 h, cells were lysed and subjected to immunoprecipitation against the FLAG-tag, combined with Phos-tag/SDS–PAGE and IB analysis. (D) Recombinant FAT10 (rFAT10) was incubated with recombinant kinases IKKβ, IKKε or MK3 for 45 min at 30°C. Subsequently, proteins were separated on a Phos-tag/SDS–PAGE followed by immunoblot analysis using the antibodies indicated. (E) HEK293 cells were prepared as described in (A). Where specified, cells were pretreated with the inhibitors indicated (10 µM each) for a total of 3 h before stimulation with TNF. One representative example out of three independent experiments with the same outcomes is shown. Source data are available for this figure.

Journal: Life Science Alliance

Article Title: FAT10 is phosphorylated by IKKβ to inhibit the antiviral type-I interferon response

doi: 10.26508/lsa.202101282

Figure Lengend Snippet: (A) HEK293 cells were transiently transfected with a His-3xFLAG-FAT10 (FLAG-FAT10) expression construct and stimulated for 24 h with TNF. Lysates were subjected to immunoprecipitation using FLAG-reactive antibodies, coupled to sepharose beads, and subsequently analyzed by Phos-tag/SDS–PAGE/IB analysis. Where indicated, cells were pretreated before TNF stimulation with the displayed inhibitors for a total of 3 h (10 µM each). (B) HEK293 cells were transiently transfected with expression plasmids for the different kinases. Cells were harvested, lysed, and subjected to immunoprecipitation using anti-FLAG or anti-HA antibodies, coupled to sepharose beads. Subsequently, the immunoprecipitated kinases were incubated with recombinant FAT10 (rFAT10) and an in vitro reaction was performed in the kinase buffer. The phosphorylation status of FAT10 was analyzed by Phos-tag/SDS–PAGE and IB. Asterisks mark unspecific background bands. (C) FLAG-FAT10 and the indicated kinases were transiently overexpressed in HEK293 cells followed by TNF stimulation. After 24 h, cells were lysed and subjected to immunoprecipitation against the FLAG-tag, combined with Phos-tag/SDS–PAGE and IB analysis. (D) Recombinant FAT10 (rFAT10) was incubated with recombinant kinases IKKβ, IKKε or MK3 for 45 min at 30°C. Subsequently, proteins were separated on a Phos-tag/SDS–PAGE followed by immunoblot analysis using the antibodies indicated. (E) HEK293 cells were prepared as described in (A). Where specified, cells were pretreated with the inhibitors indicated (10 µM each) for a total of 3 h before stimulation with TNF. One representative example out of three independent experiments with the same outcomes is shown. Source data are available for this figure.

Article Snippet: When indicated, cells were pretreated for 3 h with the following inhibitors: 10 μM IKK-16 (pan-IKK inhibitor, S2882; Selleckchem), 10 μM SP600125 (pan-JNK inhibitor, S1460; Selleckchem), 10 μM SB203580 (p38 MAPK inhibitor, S1076; Selleckchem), 10 μM trametinib (MEK1/2 inhibitor, S2673; Selleckchem), 5 μM TPCA-1 (IKKβ inhibitor, SC-203083; Santa Cruz) or 10 μM CAY10576 (IKKε inhibitor, 10011249; Cayman).

Techniques: Transfection, Expressing, Construct, Immunoprecipitation, SDS Page, Incubation, Recombinant, In Vitro, Phospho-proteomics, FLAG-tag, Western Blot

(A) FAT10 mRNA levels were analyzed and quantified by real-time PCR in A549 cells 24 h after TNF/IFNγ treatment or 24 h after IAV infection. (B) A549 cells were infected with IAV (MOI:1) for 0, 6, 24 or 48 h, as indicated. Cell lysates were subjected to SDS–PAGE combined with immunoblot analysis with the antibodies indicated. (C) Immunoblot showing endogenous FAT10 expression in A549 cells treated for 24 h with TNF/IFNγ, or infected for 24 h with IAV. FAT10 was immunoprecipitated with a monoclonal FAT10-reactive antibody (clone 4F1) and an immunoblot was performed with the antibodies indicated. (D) A549 cells stably expressing His-3xFLAG-FAT10 (FLAG-FAT10) were lysed after 24 h of TNF stimulation or after 24 h of IAV infection. The lysates were subjected to immunoprecipitation using FLAG-reactive antibodies coupled to sepharose beads. Subsequently, a Phos-tag/SDS–PAGE and immunoblot analysis with the indicated antibodies was performed. Asterisk marks an unspecific background band. (E) Recombinant 6His-SUMO-FAT10 was purified via Ni-NTA and left bound to the beads. 400 units λ phosphatase was added and incubated twice for 30 min at 30°C. Beads were extensively washed and FAT10 was eluted by treatment with the ULP1 enzyme to receive untagged and non-phosphorylated FAT10. Lysates from untreated or IAV-infected A549 cells were prepared and incubated with the purified FAT10, as indicated, for 30 min at 30°C. Proteins were separated on a Phos-tag/SDS–PAGE and analyzed by immunoblotting with a FAT10-reactive, polyclonal antibody. (F) A549 cells stably expressing FLAG-FAT10 were infected with IAV for 24 h. Cell lysates were subjected to a FLAG-immunoprecipitation and analyzed by Phos-tag/SDS–PAGE, followed by immunoblotting using the antibodies indicated. Where indicated, cells were pretreated with the indicated inhibitors (5 mM IKKβ inhibitor, 10 μM IKKε inhibitor) for 3 h, before IAV infection. For each panel, one representative example out of three independent experiments with similar outcomes is shown. Source data are available for this figure.

Journal: Life Science Alliance

Article Title: FAT10 is phosphorylated by IKKβ to inhibit the antiviral type-I interferon response

doi: 10.26508/lsa.202101282

Figure Lengend Snippet: (A) FAT10 mRNA levels were analyzed and quantified by real-time PCR in A549 cells 24 h after TNF/IFNγ treatment or 24 h after IAV infection. (B) A549 cells were infected with IAV (MOI:1) for 0, 6, 24 or 48 h, as indicated. Cell lysates were subjected to SDS–PAGE combined with immunoblot analysis with the antibodies indicated. (C) Immunoblot showing endogenous FAT10 expression in A549 cells treated for 24 h with TNF/IFNγ, or infected for 24 h with IAV. FAT10 was immunoprecipitated with a monoclonal FAT10-reactive antibody (clone 4F1) and an immunoblot was performed with the antibodies indicated. (D) A549 cells stably expressing His-3xFLAG-FAT10 (FLAG-FAT10) were lysed after 24 h of TNF stimulation or after 24 h of IAV infection. The lysates were subjected to immunoprecipitation using FLAG-reactive antibodies coupled to sepharose beads. Subsequently, a Phos-tag/SDS–PAGE and immunoblot analysis with the indicated antibodies was performed. Asterisk marks an unspecific background band. (E) Recombinant 6His-SUMO-FAT10 was purified via Ni-NTA and left bound to the beads. 400 units λ phosphatase was added and incubated twice for 30 min at 30°C. Beads were extensively washed and FAT10 was eluted by treatment with the ULP1 enzyme to receive untagged and non-phosphorylated FAT10. Lysates from untreated or IAV-infected A549 cells were prepared and incubated with the purified FAT10, as indicated, for 30 min at 30°C. Proteins were separated on a Phos-tag/SDS–PAGE and analyzed by immunoblotting with a FAT10-reactive, polyclonal antibody. (F) A549 cells stably expressing FLAG-FAT10 were infected with IAV for 24 h. Cell lysates were subjected to a FLAG-immunoprecipitation and analyzed by Phos-tag/SDS–PAGE, followed by immunoblotting using the antibodies indicated. Where indicated, cells were pretreated with the indicated inhibitors (5 mM IKKβ inhibitor, 10 μM IKKε inhibitor) for 3 h, before IAV infection. For each panel, one representative example out of three independent experiments with similar outcomes is shown. Source data are available for this figure.

Article Snippet: When indicated, cells were pretreated for 3 h with the following inhibitors: 10 μM IKK-16 (pan-IKK inhibitor, S2882; Selleckchem), 10 μM SP600125 (pan-JNK inhibitor, S1460; Selleckchem), 10 μM SB203580 (p38 MAPK inhibitor, S1076; Selleckchem), 10 μM trametinib (MEK1/2 inhibitor, S2673; Selleckchem), 5 μM TPCA-1 (IKKβ inhibitor, SC-203083; Santa Cruz) or 10 μM CAY10576 (IKKε inhibitor, 10011249; Cayman).

Techniques: Real-time Polymerase Chain Reaction, Infection, SDS Page, Western Blot, Expressing, Immunoprecipitation, Stable Transfection, Recombinant, Purification, Incubation

(A) Tax activates IKK in a cell-free system. Cell extracts (S100) of Jurkat T or NEMO-deficient Jurkat T cells were incubated with Tax WT or M22 (100 nM each), and ATP for 1 h at 30°C. Recombinant NEMO (100 nM) was added into the NEMO-deficient extracts to restore IKK activation. IKK activation was detected by phosphorylation of IKKα, IKKβ and its substrate IκBα. (B) Tax activates NF-κB in cells. 293T cells in 12-well-plates were transfected with 1, 10 or 100 ng of plasmids encoding Tax WT or M22, together with a NF-κB firefly-luciferase reporter and a renilla-luciferase reporter (internal control). The firefly-luciferase activity was measured 24 h later and normalized by renilla-luciferase. Tax protein expression was detected by immunoblotting with an anti-Tax antibody. FH: FLAG-10xHis tag.

Journal: PLoS Pathogens

Article Title: HTLV-1 Tax Functions as a Ubiquitin E3 Ligase for Direct IKK Activation via Synthesis of Mixed-Linkage Polyubiquitin Chains

doi: 10.1371/journal.ppat.1005584

Figure Lengend Snippet: (A) Tax activates IKK in a cell-free system. Cell extracts (S100) of Jurkat T or NEMO-deficient Jurkat T cells were incubated with Tax WT or M22 (100 nM each), and ATP for 1 h at 30°C. Recombinant NEMO (100 nM) was added into the NEMO-deficient extracts to restore IKK activation. IKK activation was detected by phosphorylation of IKKα, IKKβ and its substrate IκBα. (B) Tax activates NF-κB in cells. 293T cells in 12-well-plates were transfected with 1, 10 or 100 ng of plasmids encoding Tax WT or M22, together with a NF-κB firefly-luciferase reporter and a renilla-luciferase reporter (internal control). The firefly-luciferase activity was measured 24 h later and normalized by renilla-luciferase. Tax protein expression was detected by immunoblotting with an anti-Tax antibody. FH: FLAG-10xHis tag.

Article Snippet: Rabbit antibodies against IKKα (sc-7218, dilution 1:1,000), IKKβ (sc-7607, dilution 1:1,000), NEMO (sc-8330, dilution 1:1,000) and mouse antibody against ubiquitin (sc-8017, dilution 1:1,000) were obtained from Santa Cruz Biotechnology; antibodies against TAK1 (ab109526, dilution 1:1,000), UbcH7 (ab108936, dilution 1:2,000), Ubc13 (ab109286, dilution 1:5,000), RNF8 (ab131221, dilution 1:1,000), p-IKKα S176 (ab138426, dilution 1:500) were from Abcam; antibodies against CYLD (#8462, dilution 1:1,000), p-TAK1 Thr187 (#4536, dilution 1:1,000), p-IKKα/β Ser176/180 (#2697, dilution 1:1,000) and p-IκBα Ser32/36 (#9246, dilution 1:1,000) were from Cell Signaling; antibodies against FLAG-tag (M20008, dilution 1:5,000) and His-tag (M20001, dilution 1:1,000) were from Abmart; antibodies against IκBα and UbcH5c were homemade; and antibody against Tax (mAB, clone Lt-4) was described in Lee et al. [ ].

Techniques: Incubation, Recombinant, Activation Assay, Phospho-proteomics, Transfection, Luciferase, Control, Activity Assay, Expressing, Western Blot

(A) Multiple E2s mediate IKK activation by Tax in vitro . The same in vitro assay as in was performed except UbcH7 was replaced with the indicated recombinant E2s. (B) E2 DN (dominant-negative) mutants impair IKK-NF-κB activation by Tax in cells. 293T cells were transfected with E2 DN mutants, or GFP as a control. After 6 hours, cells were transfected again with plasmids encoding Tax or TRAF6, together with a NF-κB firefly-luciferase reporter and a renilla-luciferase internal control. The luciferase activity was measured and normalized by renilla luciferase. Protein expression was detected by immunoblotting with an anti-FLAG antibody. FH: FLAG-10xHis tag.

Journal: PLoS Pathogens

Article Title: HTLV-1 Tax Functions as a Ubiquitin E3 Ligase for Direct IKK Activation via Synthesis of Mixed-Linkage Polyubiquitin Chains

doi: 10.1371/journal.ppat.1005584

Figure Lengend Snippet: (A) Multiple E2s mediate IKK activation by Tax in vitro . The same in vitro assay as in was performed except UbcH7 was replaced with the indicated recombinant E2s. (B) E2 DN (dominant-negative) mutants impair IKK-NF-κB activation by Tax in cells. 293T cells were transfected with E2 DN mutants, or GFP as a control. After 6 hours, cells were transfected again with plasmids encoding Tax or TRAF6, together with a NF-κB firefly-luciferase reporter and a renilla-luciferase internal control. The luciferase activity was measured and normalized by renilla luciferase. Protein expression was detected by immunoblotting with an anti-FLAG antibody. FH: FLAG-10xHis tag.

Article Snippet: Rabbit antibodies against IKKα (sc-7218, dilution 1:1,000), IKKβ (sc-7607, dilution 1:1,000), NEMO (sc-8330, dilution 1:1,000) and mouse antibody against ubiquitin (sc-8017, dilution 1:1,000) were obtained from Santa Cruz Biotechnology; antibodies against TAK1 (ab109526, dilution 1:1,000), UbcH7 (ab108936, dilution 1:2,000), Ubc13 (ab109286, dilution 1:5,000), RNF8 (ab131221, dilution 1:1,000), p-IKKα S176 (ab138426, dilution 1:500) were from Abcam; antibodies against CYLD (#8462, dilution 1:1,000), p-TAK1 Thr187 (#4536, dilution 1:1,000), p-IKKα/β Ser176/180 (#2697, dilution 1:1,000) and p-IκBα Ser32/36 (#9246, dilution 1:1,000) were from Cell Signaling; antibodies against FLAG-tag (M20008, dilution 1:5,000) and His-tag (M20001, dilution 1:1,000) were from Abmart; antibodies against IκBα and UbcH5c were homemade; and antibody against Tax (mAB, clone Lt-4) was described in Lee et al. [ ].

Techniques: Activation Assay, In Vitro, Recombinant, Dominant Negative Mutation, Transfection, Control, Luciferase, Activity Assay, Expressing, Western Blot

(A) IKK complex purified from 293F/NEMO-FLAG knock-in cells was incubated with recombinant E1, Ub, UbcH7 WT or C86A mutant and Tax in ATP buffer at 37°C for 2 h. IKK activation was determined by phosphorylation of IKKα and IKKβ. Polyubiquitin chains were detected by anti-ubiquitin immunoblotting. IKKα, IKKβ and NEMO were also blotted. (B) The same assay as in (A) was performed except the UbcH7 was replaced by UbcH5c or its enzymatic-dead mutant C85A.

Journal: PLoS Pathogens

Article Title: HTLV-1 Tax Functions as a Ubiquitin E3 Ligase for Direct IKK Activation via Synthesis of Mixed-Linkage Polyubiquitin Chains

doi: 10.1371/journal.ppat.1005584

Figure Lengend Snippet: (A) IKK complex purified from 293F/NEMO-FLAG knock-in cells was incubated with recombinant E1, Ub, UbcH7 WT or C86A mutant and Tax in ATP buffer at 37°C for 2 h. IKK activation was determined by phosphorylation of IKKα and IKKβ. Polyubiquitin chains were detected by anti-ubiquitin immunoblotting. IKKα, IKKβ and NEMO were also blotted. (B) The same assay as in (A) was performed except the UbcH7 was replaced by UbcH5c or its enzymatic-dead mutant C85A.

Article Snippet: Rabbit antibodies against IKKα (sc-7218, dilution 1:1,000), IKKβ (sc-7607, dilution 1:1,000), NEMO (sc-8330, dilution 1:1,000) and mouse antibody against ubiquitin (sc-8017, dilution 1:1,000) were obtained from Santa Cruz Biotechnology; antibodies against TAK1 (ab109526, dilution 1:1,000), UbcH7 (ab108936, dilution 1:2,000), Ubc13 (ab109286, dilution 1:5,000), RNF8 (ab131221, dilution 1:1,000), p-IKKα S176 (ab138426, dilution 1:500) were from Abcam; antibodies against CYLD (#8462, dilution 1:1,000), p-TAK1 Thr187 (#4536, dilution 1:1,000), p-IKKα/β Ser176/180 (#2697, dilution 1:1,000) and p-IκBα Ser32/36 (#9246, dilution 1:1,000) were from Cell Signaling; antibodies against FLAG-tag (M20008, dilution 1:5,000) and His-tag (M20001, dilution 1:1,000) were from Abmart; antibodies against IκBα and UbcH5c were homemade; and antibody against Tax (mAB, clone Lt-4) was described in Lee et al. [ ].

Techniques: Purification, Knock-In, Incubation, Recombinant, Mutagenesis, Activation Assay, Phospho-proteomics, Ubiquitin Proteomics, Western Blot

(A) Ubiquitin mutants impair IKK activation by Tax. Jurkat T S100 was incubated with Tax and the indicated ubiquitin mutants in ATP buffer at 30°C for 1 h. IKK activation was detected by phosphorylation of IκBα. (B) Jurkat T S100 was incubated with Tax and different concentrations of CYLD or its enzymatic-dead mutant C601A. IKK activation was detected by phosphorylation of IκBα. (C) The same assay as in (B) was performed except CYLD was replaced by vOTU or its enzymatic-dead mutant C40A. (D) Interaction between NEMO and ubiquitin chains is required for Tax-dependent IKK activation. Cell extracts (S100) of NEMO-deficient Jurkat T (C2) cells were incubated with Tax and NEMO WT or the indicated mutants (100 nM each) in ATP buffer at 30°C for 1 h. IKK activation was detected by phosphorylation of IKKβ and its substrate IκBα. (E) Mixed-linkage polyUb chains synthesized by Tax activate IKK directly. Purified IKK complex was incubated with the indicated polyUb chains (prepared and purified as described in ) in ATP buffer at 37°C for 2 h. IKK activation was detected by phosphorylation of IKKβ. Mixed: Mixed linkage polyUb chains synthesized by Tax and UbcH5c. K63: K63 linkage polyUb chains synthesized by TRAF6 and Ubc13/Uev2. K48: K48 linkage polyUb chains synthesized by IpaH and UbcH5c. Linear: Linear linkage polyUb chains synthesized by HOIP-RBRC and UbcH7.

Journal: PLoS Pathogens

Article Title: HTLV-1 Tax Functions as a Ubiquitin E3 Ligase for Direct IKK Activation via Synthesis of Mixed-Linkage Polyubiquitin Chains

doi: 10.1371/journal.ppat.1005584

Figure Lengend Snippet: (A) Ubiquitin mutants impair IKK activation by Tax. Jurkat T S100 was incubated with Tax and the indicated ubiquitin mutants in ATP buffer at 30°C for 1 h. IKK activation was detected by phosphorylation of IκBα. (B) Jurkat T S100 was incubated with Tax and different concentrations of CYLD or its enzymatic-dead mutant C601A. IKK activation was detected by phosphorylation of IκBα. (C) The same assay as in (B) was performed except CYLD was replaced by vOTU or its enzymatic-dead mutant C40A. (D) Interaction between NEMO and ubiquitin chains is required for Tax-dependent IKK activation. Cell extracts (S100) of NEMO-deficient Jurkat T (C2) cells were incubated with Tax and NEMO WT or the indicated mutants (100 nM each) in ATP buffer at 30°C for 1 h. IKK activation was detected by phosphorylation of IKKβ and its substrate IκBα. (E) Mixed-linkage polyUb chains synthesized by Tax activate IKK directly. Purified IKK complex was incubated with the indicated polyUb chains (prepared and purified as described in ) in ATP buffer at 37°C for 2 h. IKK activation was detected by phosphorylation of IKKβ. Mixed: Mixed linkage polyUb chains synthesized by Tax and UbcH5c. K63: K63 linkage polyUb chains synthesized by TRAF6 and Ubc13/Uev2. K48: K48 linkage polyUb chains synthesized by IpaH and UbcH5c. Linear: Linear linkage polyUb chains synthesized by HOIP-RBRC and UbcH7.

Article Snippet: Rabbit antibodies against IKKα (sc-7218, dilution 1:1,000), IKKβ (sc-7607, dilution 1:1,000), NEMO (sc-8330, dilution 1:1,000) and mouse antibody against ubiquitin (sc-8017, dilution 1:1,000) were obtained from Santa Cruz Biotechnology; antibodies against TAK1 (ab109526, dilution 1:1,000), UbcH7 (ab108936, dilution 1:2,000), Ubc13 (ab109286, dilution 1:5,000), RNF8 (ab131221, dilution 1:1,000), p-IKKα S176 (ab138426, dilution 1:500) were from Abcam; antibodies against CYLD (#8462, dilution 1:1,000), p-TAK1 Thr187 (#4536, dilution 1:1,000), p-IKKα/β Ser176/180 (#2697, dilution 1:1,000) and p-IκBα Ser32/36 (#9246, dilution 1:1,000) were from Cell Signaling; antibodies against FLAG-tag (M20008, dilution 1:5,000) and His-tag (M20001, dilution 1:1,000) were from Abmart; antibodies against IκBα and UbcH5c were homemade; and antibody against Tax (mAB, clone Lt-4) was described in Lee et al. [ ].

Techniques: Ubiquitin Proteomics, Activation Assay, Incubation, Phospho-proteomics, Mutagenesis, Synthesized, Purification

(A) Ubiquitin R63 mutant impairs IKK activation by Tax. The same assay as in was performed except ubiquitin was replaced by Ub R48 or R63 mutants. (B) Polyubiquitin chains pre-synthesized by E1, UbcH5c, Tax and Ub WT or the indicated mutants were incubated with purified IKK complex, in ATP buffer at 37°C for 2 h. IKK activation was detected by phosphorylation of IKKβ. (C) Ub R63 is inefficient in polyubiquitination by Tax. Tax was incubated with E1, UbcH5c, and the indicated Ub in ATP buffer at 37°C for the indicated time. Synthesis of polyUb chains was determined by immunoblotting using anti-Ub antibody. (D) Model illustrating IKK activation by Tax.

Journal: PLoS Pathogens

Article Title: HTLV-1 Tax Functions as a Ubiquitin E3 Ligase for Direct IKK Activation via Synthesis of Mixed-Linkage Polyubiquitin Chains

doi: 10.1371/journal.ppat.1005584

Figure Lengend Snippet: (A) Ubiquitin R63 mutant impairs IKK activation by Tax. The same assay as in was performed except ubiquitin was replaced by Ub R48 or R63 mutants. (B) Polyubiquitin chains pre-synthesized by E1, UbcH5c, Tax and Ub WT or the indicated mutants were incubated with purified IKK complex, in ATP buffer at 37°C for 2 h. IKK activation was detected by phosphorylation of IKKβ. (C) Ub R63 is inefficient in polyubiquitination by Tax. Tax was incubated with E1, UbcH5c, and the indicated Ub in ATP buffer at 37°C for the indicated time. Synthesis of polyUb chains was determined by immunoblotting using anti-Ub antibody. (D) Model illustrating IKK activation by Tax.

Article Snippet: Rabbit antibodies against IKKα (sc-7218, dilution 1:1,000), IKKβ (sc-7607, dilution 1:1,000), NEMO (sc-8330, dilution 1:1,000) and mouse antibody against ubiquitin (sc-8017, dilution 1:1,000) were obtained from Santa Cruz Biotechnology; antibodies against TAK1 (ab109526, dilution 1:1,000), UbcH7 (ab108936, dilution 1:2,000), Ubc13 (ab109286, dilution 1:5,000), RNF8 (ab131221, dilution 1:1,000), p-IKKα S176 (ab138426, dilution 1:500) were from Abcam; antibodies against CYLD (#8462, dilution 1:1,000), p-TAK1 Thr187 (#4536, dilution 1:1,000), p-IKKα/β Ser176/180 (#2697, dilution 1:1,000) and p-IκBα Ser32/36 (#9246, dilution 1:1,000) were from Cell Signaling; antibodies against FLAG-tag (M20008, dilution 1:5,000) and His-tag (M20001, dilution 1:1,000) were from Abmart; antibodies against IκBα and UbcH5c were homemade; and antibody against Tax (mAB, clone Lt-4) was described in Lee et al. [ ].

Techniques: Ubiquitin Proteomics, Mutagenesis, Activation Assay, Synthesized, Incubation, Purification, Phospho-proteomics, Western Blot

Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with IKKε. A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.

Journal: The Journal of biological chemistry

Article Title: SAMHD1 impairs type I interferon induction through the MAVS, IKKε, and IRF7 signaling axis during viral infection.

doi: 10.1016/j.jbc.2023.104925

Figure Lengend Snippet: Figure 3. SAMHD1 suppresses MAVS aggregation and disrupts MAVS interaction with IKKε. A, THP-1 Ctrl and SAMHD1 KO cells were mock-infected or infected with SeV (MOI of 10) for 8 h. Crude mitochondria were isolated and subjected to SDD-AGE (top). Whole cell lysates were analyzed by SDS-PAGE (bottom). Quantification of pTBK1 (S172) and pIRF3 (S396) levels was performed by densitometry and normalized relative to total TBK1 and IRF3, respectively. B, HEK293T cells were transfected with expression plasmids encoding the indicated proteins (FLAG-MAVS, myc-IKKε, and increasing amounts of HA-SAMHD1). Cells were lysed 36 h posttransfection, and IP was performed using an anti-FLAG antibody. Indicated proteins were detected by IB. C, THP-1 Ctrl and SAMHD1 cells were mock-infected (M) or infected with SeV (MOI of 10) and harvested at the indicated time points. Cell lysates were analyzed by IB with the indicated antibodies. Quantification of pIKKε (S172) levels was performed by densitometry and expressed relative to total IKKε. A–C, representative results from three independent experiments are shown. IB, immunoblot; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; M, mock infection; MAVS, mitochondrial antiviral-signaling protein; MOI, multiplicity of infection; pIKKε, phospho-IKKε; SAMHD, sterile alpha motif and HD domain-containing protein; SDD-AGE, semidenaturing detergent agarose gel electrophoresis; SeV, Sendai virus; SeV NP, nucleoprotein of SeV; TBK1, TANK binding kinase 1.

Article Snippet: FLAG-tagged kinaseinactive IKKε K38A was a gift from Tom Maniatis (Addgene plasmid #26202). plentiCRISPR v2-Blasticidin was a gift from Mohan Babu (Addgene plasmid # 83480).

Techniques: Infection, Isolation, SDS Page, Transfection, Expressing, Western Blot, Sterility, Agarose Gel Electrophoresis, Virus, Binding Assay

Figure 4. SAMHD1 inhibits IKKε-mediated IFN-I signaling and disrupts IRF7 binding to the IKKε kinase domain. A, recombinant SAMHD1 and IKKε purified from Escherichia coli and HEK293T cells, respectively, were pulled down with an anti-SAMHD1 antibody and analyzed by IB. Representative data from two independent experiments are shown. B, HEK293T cells were cotransfected with increasing amounts of plasmid encoding HA-SAMHD1, IFN-β- luciferase reporter, renilla-TK, and myc-tagged IKKε. Dual luciferase assay was performed at 24 h posttransfection, and cell lysates were harvested for IB. Error bars represent mean ± SD. Statistical significance was determined using one-way ANOVA; ***p < 0.001 compared with the vector control in the same group. C, schematic representation of full-length (FL) human IKKε (top). Five myc-tagged C-terminal and N-terminal deletion mutants are represented by the solid bars below the FL IKKε. The aa numbers of IKKε are shown. D–F, HEK293T cells were cotransfected with plasmids encoding HA-SAMHD1 and myc- tagged IKKε FL or C-terminal deletion mutants (D), IKKε N-terminal deletion lacking the kinase domain (ΔKD) (E), or IKKε kinase-inactive mutant K38A (F). Cells were lysed, and IP was performed using anti-HA antibody at 36 h posttransfection. Nonspecific IgG was used as a negative control in IP, and the indicated proteins were detected by IB. G, HEK293T cells were cotransfected with myc-IKKε KD, FLAG-IRF7, and HA-SAMHD1. Cells were lysed, and IP was performed using anti-myc antibody at 36 h posttransfection. The indicated proteins were detected by IB. A and B and D–G, representative data from three independent experiments are shown. HLH, helix-loop-helix domain; IB, immunoblot; IFN, interferon; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; KD, kinase domain; LZ, leucine zipper domain; SAMHD, sterile alpha motif and HD domain-containing protein; ULD, ubiquitin-like domain; V, vector controls; WT, wild-type.

Journal: The Journal of biological chemistry

Article Title: SAMHD1 impairs type I interferon induction through the MAVS, IKKε, and IRF7 signaling axis during viral infection.

doi: 10.1016/j.jbc.2023.104925

Figure Lengend Snippet: Figure 4. SAMHD1 inhibits IKKε-mediated IFN-I signaling and disrupts IRF7 binding to the IKKε kinase domain. A, recombinant SAMHD1 and IKKε purified from Escherichia coli and HEK293T cells, respectively, were pulled down with an anti-SAMHD1 antibody and analyzed by IB. Representative data from two independent experiments are shown. B, HEK293T cells were cotransfected with increasing amounts of plasmid encoding HA-SAMHD1, IFN-β- luciferase reporter, renilla-TK, and myc-tagged IKKε. Dual luciferase assay was performed at 24 h posttransfection, and cell lysates were harvested for IB. Error bars represent mean ± SD. Statistical significance was determined using one-way ANOVA; ***p < 0.001 compared with the vector control in the same group. C, schematic representation of full-length (FL) human IKKε (top). Five myc-tagged C-terminal and N-terminal deletion mutants are represented by the solid bars below the FL IKKε. The aa numbers of IKKε are shown. D–F, HEK293T cells were cotransfected with plasmids encoding HA-SAMHD1 and myc- tagged IKKε FL or C-terminal deletion mutants (D), IKKε N-terminal deletion lacking the kinase domain (ΔKD) (E), or IKKε kinase-inactive mutant K38A (F). Cells were lysed, and IP was performed using anti-HA antibody at 36 h posttransfection. Nonspecific IgG was used as a negative control in IP, and the indicated proteins were detected by IB. G, HEK293T cells were cotransfected with myc-IKKε KD, FLAG-IRF7, and HA-SAMHD1. Cells were lysed, and IP was performed using anti-myc antibody at 36 h posttransfection. The indicated proteins were detected by IB. A and B and D–G, representative data from three independent experiments are shown. HLH, helix-loop-helix domain; IB, immunoblot; IFN, interferon; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; KD, kinase domain; LZ, leucine zipper domain; SAMHD, sterile alpha motif and HD domain-containing protein; ULD, ubiquitin-like domain; V, vector controls; WT, wild-type.

Article Snippet: FLAG-tagged kinaseinactive IKKε K38A was a gift from Tom Maniatis (Addgene plasmid #26202). plentiCRISPR v2-Blasticidin was a gift from Mohan Babu (Addgene plasmid # 83480).

Techniques: Binding Assay, Recombinant, Plasmid Preparation, Luciferase, Control, Mutagenesis, Negative Control, Western Blot, Sterility, Ubiquitin Proteomics

Figure 10. SAMHD1 impairs IFN-I induction through the MAVS, IKKε, and IRF7 signaling axis during viral infection. SAMHD1 inhibits MAVS- and IKKε-mediated IFN-I induction in monocytic cells. Mechanistically, SAMHD1 interacts with the CARD of MAVS and suppresses MAVS aggre- gation, resulting in reduced IKKε recruitment to MAVS and IKKε phos- phorylation (indicated with a letter P). SAMHD1 also binds to the kinase domain of IKKε and disrupts binding of IRF7 to IKKε KD. SAMHD1 sup- pression of the IRF7-mediated antiviral response depends on its interaction with the inhibitory domain of IRF7. Our results also indicated that endog- enous IRF7 in THP-1 cells is required for efficient HIV-1 infection and viral gene expression. The red T-shaped symbols indicate inhibitory functions confirmed in experiments, while the black T-shaped symbols indicate pro- posed inhibitory mechanisms. This figure was created with BioRender.com. CARD, caspase-recruitment domain; HIV, human immunodeficiency virus; IFN, interferon; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; KD, kinase domain; MAVS, mitochondrial antiviral- signaling protein; SAMHD, sterile alpha motif and HD domain-containing protein.

Journal: The Journal of biological chemistry

Article Title: SAMHD1 impairs type I interferon induction through the MAVS, IKKε, and IRF7 signaling axis during viral infection.

doi: 10.1016/j.jbc.2023.104925

Figure Lengend Snippet: Figure 10. SAMHD1 impairs IFN-I induction through the MAVS, IKKε, and IRF7 signaling axis during viral infection. SAMHD1 inhibits MAVS- and IKKε-mediated IFN-I induction in monocytic cells. Mechanistically, SAMHD1 interacts with the CARD of MAVS and suppresses MAVS aggre- gation, resulting in reduced IKKε recruitment to MAVS and IKKε phos- phorylation (indicated with a letter P). SAMHD1 also binds to the kinase domain of IKKε and disrupts binding of IRF7 to IKKε KD. SAMHD1 sup- pression of the IRF7-mediated antiviral response depends on its interaction with the inhibitory domain of IRF7. Our results also indicated that endog- enous IRF7 in THP-1 cells is required for efficient HIV-1 infection and viral gene expression. The red T-shaped symbols indicate inhibitory functions confirmed in experiments, while the black T-shaped symbols indicate pro- posed inhibitory mechanisms. This figure was created with BioRender.com. CARD, caspase-recruitment domain; HIV, human immunodeficiency virus; IFN, interferon; IKKε, inhibitor of nuclear factor kappa-B kinase epsilon; IRF, IFN regulatory factor; KD, kinase domain; MAVS, mitochondrial antiviral- signaling protein; SAMHD, sterile alpha motif and HD domain-containing protein.

Article Snippet: FLAG-tagged kinaseinactive IKKε K38A was a gift from Tom Maniatis (Addgene plasmid #26202). plentiCRISPR v2-Blasticidin was a gift from Mohan Babu (Addgene plasmid # 83480).

Techniques: Infection, Binding Assay, Gene Expression, Virus, Sterility

KEY RESOURCES TABLE

Journal: Molecular cell

Article Title: Stabilization of ERK-Phosphorylated METTL3 by USP5 Increases m 6 A Methylation

doi: 10.1016/j.molcel.2020.10.026

Figure Lengend Snippet: KEY RESOURCES TABLE

Article Snippet: Human Flag-IKKε , Addgene , 26201.

Techniques: Control, Recombinant, Luciferase, Mutagenesis, Modification, Multiplex Assay, CRISPR, Generated, Ubiquitin Proteomics, Software