Fig. 7
From: Nuclear Smad6 promotes gliomagenesis by negatively regulating PIAS3-mediated STAT3 inhibition
MH2 domain is essential for Smad6-mediated PIAS3 ubiquitination and proteasomal degradation. a Smad6-MH2 deletion mutant failed to induce PIAS3 ubiquitination and degradation. 293T cells were transfected with expression constructs in the indicated combinations. b Nuclear-MH2 antagonized the ubiquitination and degradation of PIAS3 induced by nuclear-Smad6 in a dose-dependent manner. 293T cells were transfected with expression constructs in the indicated combinations and concentrations (0, 0.5, 1.0 μg per well in a 6-well plate). c Nuclear-MH2 rescued nuclear-Smad6 induced PIAS3 downregulation in A172 and T98G cells. d Nuclear-MH2 increased endogenous PIAS3 levels in U87 and U251 cells. e Nuclear-MH2 inhibited tumor growth in nude mice. U87 cells with nuclear-MH2 OE or Mock were used for tumor formation in a nude mouse xenograft model, and mean tumor volumes and average tumor weight of xenograft tumors were measured (n = 6). f MH2 introduction increased PIAS3 expression and impaired STAT3 downstream genes (CCND1 and SOX2) expression in xenograft tumors (n = 6). Data were represented as means ± SD and analyzed using two-tailed Student’s t-test. **P < 0.01
