ISWI chromatin remodeler SMARCA5 is essential for meiotic gene expression and male fertility in mammals

Regulation of the transcriptome to promote meiosis is important for sperm development and fertility. However, how chromatin remodeling directs the transcriptome during meiosis in male germ cells is largely unknown. Here, we demonstrate that the ISWI family ATP-dependent chromatin remodeling factor SMARCA5 (SNF2H) plays a critical role in regulating meiotic prophase progression during spermatogenesis. Males with germ cell-specific depletion of SMARCA5 are infertile and unable to form sperm. Loss of Smarca5 results in failure of meiotic progression with abnormal spermatocytes beginning at the pachytene stage and an aberrant global increase in chromatin accessibility, especially at genes important for meiotic prophase.