WTAP Function in Sertoli Cells Is Essential for Sustaining the Spermatogonial Stem Cell Niche

Summary Sertoli cells are the major component of the spermatogonial stem cell (SSC) niche; however, regulatory mechanisms in Sertoli cells that dictate SSC fate decisions remain largely unknown. Here we revealed features of the N6-methyladenosine (m6A) mRNA modification in Sertoli cells and demonstrated the functions of WTAP, the key subunit of the m6A methyltransferase complex in spermatogenesis. m6A-sequencing analysis identified 21,909 m6A sites from 15,365 putative m6A-enriched transcripts within 6,122 genes, including many Sertoli cell-specific genes. Conditional deletion of Wtap in Sertoli cells resulted in sterility and the progressive loss of the SSC population. RNA sequencing and ribosome nascent-chain complex-bound mRNA sequencing analyses suggested that alternative splicing events of transcripts encoding SSC niche factors were sharply altered and translation of these transcripts were severely dysregulated by Wtap deletion. Collectively, this study uncovers a novel regulatory mechanism of the SSC niche and provide insights into molecular interactions between stem cells and their cognate niches in mammals.

Graphical Abstract

Highlights • WTAP is highly expressed in Sertoli cell and is essential in spermatogenesis • Wtap knockout in Sertoli cell causes defective spermatogonial stem cell maintenance • WTAP regulates transcription and translation of m6A-enriched genes in Sertoli cell

In this article, Yang and colleagues revealed features of m6A modification in Sertoli cells and showed that WTAP deficiency causes dysregulated transcripts encoding spermatogonial stem cell (SSC) niche factors and the progressive loss of SSCs. They conclude that WTAP-mediated m6A in Sertoli cell is indispensable for sustaining SSC niche.