[MGRN1 affects the mitophagy of spermatogonial stem cells in mice]

To study the effect of mahogunin ring finger-1 (MGRN1) on the mitophagy of the spermatogonial stem cells (SSC) in mice.

SSCs cultured in vitro were divided into three groups: empty vector control, MGRN1 (MGRN1 in SSCs knocked down by RNAi), and MGRN1 + FCCP (inducing mitophagy with carbonyl cyanide p-trifluoromethoxyphenylhydrazone ［FCCP］ in the SSCs with down-regulated MGRN1). The expressions of mitochondrial function-related proteins (Cytochromo c and COX IV) and mitophagy-related proteins (LC3, P62, FUNDC1 and CK2) and the phosphorylation of FUNDC1 were detected by Western blot. Mitochondria and mitochondrial autophagosomes in the SSCs were observed under the electron microscope.

Compared with the empty vector control group, the MGRN1 and MGRN1 + FCCP groups showed significantly down-regulated expressions of Cytochromo c, Cox IV, LC3 and P62, increased phosphorylation level of FUNDC1, and up-regulated expression of CK2 in the SSCs (P < 0.05). No statistically significant differences were found in the expressions of Cytochromo c, Cox IV, LC3, P62 and CK2 or in the phosphorylation level of FUNDC1 between the MGRN1 and MGRN1 + FCCP groups (P > 0.05). Electron microscopy manifested increased mitochondrial damage and reduced mitochondrial autophagosomes in the SSCs in the MGRN1 and MGRN1 + FCCP groups compared with those in the control group.

MGRN1 affects mitophagy in the SSCs of mice, which may be associated with the effect of CK2 on the phosphorylation of FUNDC1, and its molecular mechanism needs to be further studied.