Cover photograph: Hematoxylin and eosin staining of testes of gamma-glutamyl carboxylase (Ggcx) Sertoli cell-specific knockout (scKO) mice at 4 months old. Microscopic observation demonstrates the emergence of large multinuclear spermatids with apoptotic alteration and intercellular space in seminiferous tubules in Ggcx scKO testis. (See related article at e00404-20.) (Copyright © 2021 American Society for Microbiology. All Rights Reserved.)