Heat shock factor 5 establishes the male germ-line meiotic sex chromosome inactivation through regulation of .

Meiotic sex chromosome inactivation is an essential event in male germ cell development, which is directed by DNA damage response signaling independent of Xist RNA to silence the transcription activity of the sex chromosomes. However, the specific mechanism of establishment and maintenance of meiotic chromosome silencing is still unclear. Here we identify the HSF5 as a testicular specific protein and the expression of which was at the onset of meiosis pachytene stage to round sperm.