PGC7 maintains the pluripotency of F9 embryonic carcinoma cells by promoting Nanog translation.

Primordial germ cell 7 (PGC7) is prominently expressed in primordial germ cells (PGCs) and embryonic stem cells (ESCs), serving as a pivotal marker for discerning stem cell pluripotency. However, the role of PGC7 in regulating core pluripotency factors remains unclear. In this study, the expression dynamics of PGC7 and pluripotency- associated proteins are systematically evaluated by quantitative reverse transcription PCR (RT-qPCR) and western blot analysis. Complementary experimental approaches including confocal immunofluorescence and Co- immunoprecipitation (Co-IP) assays are subsequently employed to establish subcellular colocalization patterns and elucidate the molecular mechanisms associated with PGC7 function. The results show that PGC7 is closely associated with the pluripotency status of F9 embryonal carcinoma (EC) cells. Notably, PGC7 can counteract the decrease in pluripotency induced by retinoic acid (RA). Ectopic expression of PGC7 in F9 EC cells enhances the translation of Nanog. Mechanistic analysis reveal that PGC7 activates Y-box binding protein 1 (YBX1) phosphorylation by enhancing the interaction between YBX1 and AKT1. The subsequent phosphorylation of YBX1 reduces its binding to Nanog mRNA and promotes the translation of Nanog. These results shed light on a previously unknown role of PGC7 in supporting the translation of Nanog, offering valuable insights into the functions of PGC7 in F9 EC cells.