Figure 5.

METTL14 increases ESRP2 protein stability via Lnc-LSG1

(A) Anti-m⁶A RIP assay showed that ESRP2 mRNA has no m⁶A modification, and METTL14 cannot regulate m⁶A level of ESRP2 mRNA. (B) Western blotting assay was performed to analyze the effect of METTL14 on the ESRP2 protein. (C) Immunohistochemical staining results of the orthotopic tumor sections stained with METTL14 and ESRP2 antibodies. Scale bars represent 200 μm. (D) In the IHC analysis of 40 ccRCC samples obtained from SRRSH cohort, the scatterplot shows the correlation between the expression of METTL14 and ESRP2 proteins in ccRCC. (E) Western blotting assay showed that the half-life of the ESRP2 protein was prolonged in 786-O OE-METTL14 cells treated with CHX (50 μg/mL) for the indicated hours. In contrast, the half-life was shortened in OSRC-2 shMETTL14-1 cells. (F) Cells were subjected to MG132 after transfection. Flag-IP followed by western blotting assay was conducted to detect the ubiquitination levels of ESRP2 protein in 786-O OE-METTL14 and shMETTL14-1 cells. (G) Overexpression of ESRP2 can abolish the metastatic ability of OSRC2 cells induced by METTL14 knockdown. (H and I) Knockdown of Lnc-LSG1 can abolish the effect of METTL14 knockdown on ESRP2 expression (H) and ubiquitination levels (I). ∗p < 0.05, ∗∗∗p < 0.001. The error bars represent ± SD of three biological replicates.