Journal: The Journal of Biological Chemistry
Article Title: The stress-activated kinase p38 mediates non-canonical activation of Src and tyrosine phosphorylation of the adapter protein TAB1
doi: 10.1016/j.jbc.2026.111200
Figure Lengend Snippet: p38 directly phosphorylates Src to increase its kinase activity. A , comparison between the substrate consensus sequence of p38α and the amino acid sequences of human Src around S75. Asterisks indicate amino acids that are common to both. B , an in vitro kinase assay using recombinant His-tagged Src and GST-tagged p38α proteins. Immunoblot analyses were performed with the primary antibodies indicated. C , the relative quantification of pS75-Src and pY419-Src, normalized to total Src, is presented as the mean ± SD of three independent experiments. p values were calculated by Welch’s two-tailed t test was applied. ∗∗ p < 0.01. D , COS-7 cells were transfected with Src and p38α (WT, CA or KD), and then treated with SB203580 for 5 h. Immunoblot analyses were performed with the primary antibodies indicated. E , the relative quantification of pS75-Src and pY419-Src, normalized to total Src, is presented as the mean ± SD of three independent experiments. p values were calculated by one-way ANOVA followed by either Tukey’s HSD test was applied. ∗∗ p < 0.01. F , Src immunoprecipitated from transfected COS-7 cells was preincubated with recombinant p38 for 60 min. After removal of p38, the tyrosine kinase activity of Src toward GST-TAB1-C at Y481 was evaluated by an additional 20-min incubation. The relative quantification of pY481-TAB1, normalized to total Src, is presented as the mean ± SD of three independent experiments. p values were calculated by Welch’s two-tailed t test was applied. ∗ p < 0.05. G , COS-7 cells were transfected with EGFP-TAB1, Src (WT or S75A), and p38α. Immunoblot analyses were performed with the primary antibodies indicated. H , the relative quantification of pY481-TAB1, normalized to total TAB1, is presented as the mean ± SD of four independent experiments. p values were calculated by one-way ANOVA followed by either Tukey’s HSD test was applied. ∗ p < 0.05.
Article Snippet: Primary antibodies for pY419-Src family kinase (2101S), total-Src (2110S), pT180/pY182-p38 (4511S), pY701-STAT1 (sc-136229), total-STAT1 (sc-346), pY576/577-FAK (3281S), and total-FAK (3285S) were purchased from Cell Signaling Technology. pS75-Src (ab79308) was from Abcam.
Techniques: Activity Assay, Comparison, Sequencing, In Vitro, Kinase Assay, Recombinant, Western Blot, Quantitative Proteomics, Two Tailed Test, Transfection, Immunoprecipitation, Incubation