Ppp1r36 Participates In Spermatogenesis And Autophagy

As a key member of the serine/threonine protein phosphatase family, protein phosphatase 1 (PP1) plays important roles in a variety of cell activities, such as meiosis, apoptosis, protein synthesis and the reassembly of cytoskeleton. Both catalytic subunit and regulatory subunits can affect the functions of protein phosphatase 1. Ppp1r36 as a regulatory subunit of protein phosphatase 1, its specific biological functions have not been elucidated.In this study, I demonstrated that the expression level of Ppplr36 in male gonad of 11.5 dpc embryo is higher than that in other periods. Subcellular location indicated that Ppp1r36 protein was mostly distributed in the sperm cells during spermatogenesis; few signals were observed in spermatocytes. Obvious expression was also detected in the acrosome of mature sperm. In addition, Ppplr36 knockdown not only affected the normal structure of the seminiferous tubules, but also resulted in the formation of abnormal sperms such as round-headed sperms, thus leading low fertilization rate.To further explore molecular mechanisms of Ppplr36, Here, I analyzed possible role of Ppplr36 in autophagy use mouse spermatogonial cell line GC-1. At the initial stage of autophagy, Ppplr36 can affect the expression level of LC3B, as well as the numbers of autophagosome puncta, which showed that Ppp1r36 promoted autophagy under starvatin conditions. Furthermore, Ppplr36 protein was colocalized with LC3B and LAMP1 respectively, and it promoted the colocalization of LC3B and LAMP1, which indicated that Ppplr36 could promote the formation of autolysosome. In addition, Ppplr36 over-expression increased both endogenous and exogenous expression levels of Atg16L, which indicated that the role of Ppplr36 in promoting autolysosome was associated with Atg16L.