E3 ubiquitin ligase RNF187 promotes growth of spermatogonia via lysine 48‐linked polyubiquitination‐mediated degradation of KRT36/KRT84

Abstract

AbstractUbiquitination is the most common post‐translational modification and is essential for various cellular regulatory processes. RNF187, which is known as RING domain AP1 coactivator‐1, is a member of the RING finger family. RNF187 can promote the proliferation and migration of various tumor cells. However, whether it has a similar role in regulating spermatogonia is not clear. This study explored the role and molecular mechanism of RNF187 in a mouse spermatogonia cell line (GC‐1). We found that RNF187 knockdown reduced the proliferation and migration of GC‐1 cells and promoted their apoptosis. RNF187 overexpression significantly increased the proliferation and migration of GC‐1 cells. In addition, we identified Keratin36/Keratin84 (KRT36/KRT84) as interactors with RNF187 by co‐immunoprecipitation and mass spectrometry analyses. RNF187 promoted GC‐1 cell growth by degrading KRT36/KRT84 via lysine 48‐linked polyubiquitination. Subsequently, we found that KRT36 or KRT84 overexpression significantly attenuated proliferation and migration of RNF187‐overexpressing GC‐1 cells. In summary, our study explored the involvement of RNF187 in regulating the growth of spermatogonia via lysine 48‐linked polyubiquitination‐mediated degradation of KRT36/KRT84. This may provide a promising new strategy for treating infertility caused by abnormal spermatogonia development.