Repurposing of the assembly chaperone PAC1-PAC2 defines a specialized proteasome landscape in mature mammalian sperm
Xuehai Zhou, Linlin Shen, Xuyang Yuan, Chen Chen, Tingfeng Wang, Zuyang Li, Jiahao Peng, Xianze Lang, Xingyan Ye, Tian Chen, Kaijian Chen, Chen Su, Zhong Huang, Yao Cong
This study identifies a specialized proteasome structure in mature mammalian sperm using cryo-EM, revealing that PAC1/2 repurposes from a chaperone to a stable regulator, defining a hyperactive 20S variant.
bioRxiv · Jun 2, 2026 · PreprintCell Biology