Journal: ACS Omega

Article Title: Identification of a Thyroid Hormone Binding Site in Hsp90 with Implications for Its Interaction with Thyroid Hormone Receptor Beta

doi: 10.1021/acsomega.2c02331

Figure Lengend Snippet: Influence of T3 on binding activity of ATP-Cy5 to Hsp90. (a) Scheme of microarray-based binding assay of ATP-Cy5 on spotted Hsp90 and ATP-Cy5 (left) in the presence of radicicol (middle) or T3 (right) and the corresponding monitoring of the bound ATP-Cy5 at the right side of the microarray. (b) Heat-map of fluorescence intensities obtained from bound ATP-Cy5 to Hsp90 or XcHtpG and (c) corresponding dose-responsive curve of T3 binding to Hsp90. Data are presented as the mean of 10 spots ± S.D. (d) Monitoring of the Hsp90-T3 interaction by MST. MST traces of Cy5-labeled Hsp90 with increasing concentrations of T3 are displayed in the mode of thermophoresis + T-jump. Different concentrations of T3 were indicated by different colored traces. Laser-induced temperature changes for F cold were from −1 to 0 s and F hot from 4 to 5 s applied, respectively. The dose-responsive fittings in (e) were performed with the function y = A 1 + ( A 2 – A 1 )/{1 + 10̂[(log x 0 – x )* p ]} between top and bottom asymptotes, with hill slope p and log x 0 as the center at indicated concentration x .

Article Snippet: This was done using a contactless GeSim Nano-Plotter (GeSim) with a nanotip pipette at a 3 mg/mL protein concentration and treated before incubation with a blocking solution Cy5-ATP label, as described earlier., ATP-Cy5 (Jenabioscience NU-814-CY5) was diluted to a constant concentration of 100 nM in buffer containing 20 mM HEPES-KOH, pH 7.3, 50 mM KCl, 5 mM MgCl 2 , 20 mM Na 2 MoO 4 , 0.01% (v/v) Tween 20, 2% (v/v) DMSO, 0.1 mg/mL BSA, and 1 mM DTT.

Techniques: Binding Assay, Activity Assay, Microarray, Fluorescence, Labeling, Concentration Assay

Journal: ACS Omega

Article Title: Identification of a Thyroid Hormone Binding Site in Hsp90 with Implications for Its Interaction with Thyroid Hormone Receptor Beta

doi: 10.1021/acsomega.2c02331

Figure Lengend Snippet: Influence of T3 or sobetirome on the interaction of Hsp90 and spotted TRb. (a) Synthesis and purification of TRb. E. coli lysate after expression of TRb (Lane 1) and after Ni-IMAC purification of TRb shown in Coomassie-stained gel (Lane 2) and the corresponding immunoblot (Lane 3). (b) Inset: microarray-based interaction assay with purified TRb and Hsp90 and Cy5-ATP. (b) Purified TRb was spotted at 3 mg/mL concentration in columns of 10 spots onto the NC microarray. After blocking, each pad was incubated overnight at 4 °C with indicated Hsp90 concentrations and 100 nM ATP-Cy5, whereas it was excluded that the spotted proteins did not bind the fluorescent label. Dose-responsive binding curve of Hsp90 on TRb with and without 10 nM T3 or sobetirome. (c) Immune detection of Hsp90 after elution from bound TRb on the Ni-IMAC resin. Lysates obtained from NIH3T3 cells pretreated for 1 h with or without 100 nM T3 or purified Hsp90 were incubated with TRb bound on the Ni-IMAC resin for 1 h on ice in the absence and presence of T3. The resin was washed with a 10-fold volume of the resin volume, and the bound protein was eluted into buffer containing 500 mM imidazole. The fractions were transferred for SDS-PAGE and immunoblot analysis. The lanes were analyzed by Hsp90 enrichment using anti Hsp90 as the primary antibody with the Lane 1 eluted fraction of NIH3T3 cell lysate without T3 pretreatment, Lane 2 eluted fraction of NIH3T3 cell lysate with T3 pretreatment, Lane 3 eluted fraction of purified Hsp90 without T3 pretreatment, Lane 4 flowthrough of purified Hsp90 without T3 pretreatment, Lane 5 eluted fraction of purified Hsp90 without T3 pretreatment, Lane 6 flowthrough of purified Hsp90 with T3 pretreatment, and Lane 7 eluted fraction of purified Hsp90 with T3 pretreatment. (d) Effect of TRb on Hsp90. The Cy5-ATP intensity of Hsp90 spotted microarray with the increase of TRb without and with T3 of 100 nM. T3-triggered TRb release from Hsp90.

Article Snippet: This was done using a contactless GeSim Nano-Plotter (GeSim) with a nanotip pipette at a 3 mg/mL protein concentration and treated before incubation with a blocking solution Cy5-ATP label, as described earlier., ATP-Cy5 (Jenabioscience NU-814-CY5) was diluted to a constant concentration of 100 nM in buffer containing 20 mM HEPES-KOH, pH 7.3, 50 mM KCl, 5 mM MgCl 2 , 20 mM Na 2 MoO 4 , 0.01% (v/v) Tween 20, 2% (v/v) DMSO, 0.1 mg/mL BSA, and 1 mM DTT.

Techniques: Purification, Expressing, Staining, Western Blot, Microarray, Concentration Assay, Blocking Assay, Incubation, Binding Assay, SDS Page

Journal: Science Advances

Article Title: CMOS electrochemical pH localizer-imager

doi: 10.1126/sciadv.abm6815

Figure Lengend Snippet: ( A ) Schematic illustration of pH-regulated enzymatic incorporation of nucleotides to substrate DNA molecules on a glass ceiling with spatioselectivity. Localized pH control induces a spatioselective deprotection of DNA strands. These deprotected strands can then be enzymatically elongated with Cy5-labeled ddATP nucleotides in parallel. The ceiling height is about 14 μm. ( B ) After parallelized enzymatic incorporation of Cy5-labeled ddATP to spatioselectively deprotected sites, epifluorescence imaging shows that the Cy5 fluorescence pattern (right) matches the randomly selected current stimulation pattern (left) exactly, thus confirming the enzymatic incorporation of nucleotides at the spatioselectively deprotected sites. The pH map at the midpoint of the 80-s-long stimulation is shown in the middle.

Article Snippet: For elongation of the deprotected strands with Cy5-labeled ddATP, the glass ceiling was spotted for 5 min with a Cy5-labeling enzymatic solution, consisting of 50 μM ddATP-Cy5 (Jena Bioscience, Jena, Germany), 8 μM TdT enzyme (Mutant F6, DNA Script, Paris, France), 1 mM CoCl 2 , and 1× TdT buffer (DNA Script, Paris, France).

Techniques: Labeling, Imaging, Fluorescence