Fig. 4

Circ-ITCH promotes the ubiquitination of HOXC10 in a BRCA1-dependent manner. Human BM-MSCs were overexpressed or silenced circ-ITCH for 48 h. (A) The protein level of HOXC10 in BM-MSCs was detected by western blot with treatment of CHX for 0, 1, 3 and 6 h. (B) The ubiquitination of HOXC10 was assessed by Co-IP assay in the presence of MG-132 treatment. Whole lysates served as input. (C) The putative E3 ubiquitin ligases of HOXC10 were predicted by Ubibrowser bioinformatics analysis. (D) The mRNA levels of NEDD4, BRCA1, MDM2, SYVN1 and SMURF1 were detected by qRT-PCR. (E) The interaction between BRCA1 and HOXC10 was detected by Co-IP assay. Whole lysates or normal IgG served as an input or negative control, respectively. (F) The mRNA levels of BRCA1 in BM-MSCs from sham or DOP rats, as well as from human BM-MSCs under microgravity simulation, were detected by qRT-PCR. *P < 0.05, **P < 0.01, and ***P < 0.001