Ubiquitination-Deficient Mutations in Human Piwi Cause Male Infertility by Impairing Histone-to-Protamine Exchange During Spermiogenesis

(Abstracted from Cell 2017;169:1090–1104) Genetic studies in worms, flies, fish, and mice indicate that the evolutionarily conserved Piwi proteins are specifically expressed during the development of the animal germline and are essential for gametogenesis in animals. Vertebrate Piwi proteins include MIWI in mice and HIWI in humans.