recombinant stat1  (Sino Biological)

Journal: Oncotarget

Article Title: Signal transducer and activator of transcription 3 (STAT3) inhibitor, S3I-201, acts as a potent and non-selective alkylating agent

doi: 10.18632/oncotarget.7838

Figure Lengend Snippet: a. Curve of 4a labeling purified STAT3 protein over a kinetic time course. SDS-PAGE image shows time-dependent increases in fluorescent intensities of STAT3 protein. The curve generated was obtained from the quantification of the relative fluorescent intensity of the respective bands within the gel. b. Purified STAT3, STAT5 and STAT1 proteins incubated with 100 μM 4a for 16 h followed by SDS-PAGE. c. Total protein images of SDS-PAGE for MDA-MB-231 cell lysates incubated with increasing doses of 4a. Total protein content observed by Coomassie Brilliant Blue staining (LEFT). Same gel viewed under fluorescent excitation conditions (RIGHT). d. Total protein images of SDS-PAGE for MDA-MB-231 cells dosed with increasing concentration of 4a prior to lysing. Total protein content observed by Coomassie Brilliant Blue staining (LEFT). Same gel viewed under fluorescent excitation conditions (RIGHT). e. SDS-PAGE of MDA-MB-231 cell lysates treated with either 4a ( O -tosyl) or 4b (sulfonamide). Total protein content of samples visualized with Coomassie Brilliant Blue staining (LEFT). Same gel viewed under fluorescent excitation (RIGHT). f. Immunobloting for total STAT3 and activated pSTAT3 levels in MDA-MB-231 cells treated with increasing concentrations of 4a. Also shown is the same gel under fluorescent excitation conditions highlighting extent of total protein labeling.

Article Snippet: Unless otherwise noted STAT proteins were purchased commercially from SignalChem: STAT3 (Catalogue # S54-54G) and STAT1 (β isoform, Catalogue # S52-54G) are present as the GST-tagged version and STAT5 (Catalogue # S56-54H) as the HIS-tagged protein.

Techniques: Labeling, Purification, SDS Page, Generated, Incubation, Staining, Concentration Assay, Western Blot