Fig. 4.

Fyn phosphorylates BCKDK at the Y151 site to increase its activity and stability to promote glioma proliferation. A, WB of BCKDK-WT and BCKDK-Y151F stable A172 or H4 cells with or without EGF (80 ng/ mL) stimulation for 30 min. B, the levels of BCKDK were detected by WB in BCKDK-WT and BCKDK-Y151F stable A172 cells treated with CHX and EGF stimulation or in BCKDK-WT and BCKDK-Y151D stable A172 cells only treated with CHX. The data are presented as the mean ± SD of three replications. C and D, the ubiquitination of the BCKDK were analyzed by WB in HEK293T cells transfected with indicated plasmids. E, Growth curves of control and BCKDK stable cell lines by MTT assay. The data are presented as the mean ± SD of three replications. (**p < 0.01, ***p < 0.001). F, Colony formation assay of control and BCKDK stable cells. G, Live images of C57 mice with luciferase-labeled GL261 cells expressing BCKDK-Y151F or BCKDK-Y151D xenografts on day 14 and day 21 are shown by bioluminescence. H, Kaplan-Meier survival curve of C57 mice. n = 8 (**p < 0.01).