摘要Meiosis is the process of producing haploid gametes through a series of complex chromosomal events and the coordinated action of various proteins.The mitochondrial protease complex(CIpXP),which consists of caseinolytic mitochondrial matrix peptidase X(CIpX)and caseinolytic protease P(CIpP)and mediates the degradation of misfolded,damaged,and oxidized proteins,is essential for maintaining mitochondrial homeostasis.CIpXP has been implicated in meiosis regulation,but its precise role is currently unknown.In this study,we engineered an inducible male germ cell-specific knockout caseinolytic mitochondrial matrix peptidase X(ClpxcKO)mouse model to investigate the function of CIpX in meiosis.We found that disrupting CIpx in male mice induced germ cell apoptosis and led to an absence of sperm in the epididymis.Specifically,it caused asynapsis of homologous chromosomes and impaired meiotic recombination,resulting in meiotic arrest in the zygotene-to-pachytene transition phase.The loss of CIpX compromised the double-strand break(DSB)repair machinery by markedly reducing the recruitment of DNA repair protein RAD51 homolog 1(RAD51)to DSB sites.This dysfunction may be due to an insufficient supply of energy from the aberrant mitochondria in ClpxcKO spermatocytes,as discerned by electron microscopy.Furthermore,ubiquitination signals on chromosomes and the expression of oxidative phosphorylation subunits were both significantly attenuated in ClpxcKO spermatocytes.Taken together,we propose that CIpX is essential for maintaining mitochondrial protein homeostasis and ensuring homologous chromosome pairing,synapsis,and recombination in spermatocytes during meiotic prophase Ⅰ.