Splicing factor SRSF1 is essential for homing of precursor spermatogonial stem cells in mice

Abstract

Spermatogonial stem cells (SSCs) are essential for continuous spermatogenesis and male fertility. The underlying mechanisms of alternative splicing (AS) in mouse SSCs are still largely unclear. We demonstrated that SRSF1 is essential for gene expression and splicing in mouse SSCs. Crosslinking immunoprecipitation and sequencing (CLIP-seq) data revealed that spermatogonia-related genes (e.g.,Plzf,Id4,Setdb1,Stra8,Tial1/Tiar,Bcas2,Ddx5,Srsf10,Uhrf1, andBud31) were bound by SRSF1 in the mouse testes. Specific deletion ofSrsf1in mouse germ cells impairs homing and self-renewal of SSCs leading to male infertility. Whole-mount staining data showed the absence of germ cells in the testes of adult cKO mice, which indicates Sertoli cell-only syndrome (SCOS) in cKO mice. The expression of spermatogonia-related genes (Gfra1,Pou5f1,Plzf,Dnd1,Stra8, andTaf4b) was significantly reduced in the testes of conditional knockout (cKO) mice. Moreover, multiomics analysis suggests that SRSF1 directly binds and regulates the expression ofTial1/Tiarvia AS to implement SSC homing and self-renewal. In addition, immunoprecipitation mass spectrometry (IP-MS) data showed that SRSF1 interacts with RNA splicing-related proteins (e.g., SRSF10, SART1, RBM15, SRRM2, SF3B6, and SF3A2). Collectively, our data reveal the critical role of SRSF1-mediated AS in SSC homing and self-renewal, which may provide a framework to elucidate the molecular mechanisms of the posttranscriptional network underlying the formation of SSC pools and the establishment of niches.