title: The E2 ubiquitin-conjugating enzyme UBE2J1 is required for spermiogenesis in mice.
abstract: ER-resident proteins destined for degradation are dislocated into the cytosol by components of the ER quality control machinery for proteasomal degradation. Dislocation substrates are ubiquitylated in the cytosol by E2 ubiquitin-conjugating/E3 ligase complexes. UBE2J1 is one of the well-characterized E2 enzymes that participate in this process. However, the physiological function of Ube2j1 is poorly defined. We find that Ube2j1(-/-) mice have reduced viability and fail to thrive early after birth. Male Ube2j1(-/-) mice are sterile due to a defect in late spermatogenesis. Ultrastructural analysis shows that removal of the cytoplasm is incomplete in Ube2j1(-/-) elongating spermatids, compromising the release of mature elongate spermatids into the lumen of the seminiferous tubule. Our findings identify an essential function for the ubiquitin-proteasome-system in spermiogenesis and define a novel, non-redundant physiological function for the dislocation step of ER quality control.
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142.
authors.forename: Paul-Albert
authors.initials: PA
authors.lastname: Koenig
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Nicholls
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142.
authors.forename: Florian I
authors.initials: FI
authors.lastname: Schmidt
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Hagiwara
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Maruyama
authors.affiliation: Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
authors.forename: Galit H
authors.initials: GH
authors.lastname: Frydman
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142.
authors.forename: Nicki
authors.initials: N
authors.lastname: Watson
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, and Howard Hughes Medical Institute, Cambridge, Massachusetts 02142.
authors.forename: David C
authors.initials: DC
authors.lastname: Page
authors.affiliation: From the Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, and ploegh@wi.mit.edu.
authors.forename: Hidde L
authors.initials: HL
authors.lastname: Ploegh
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D004721:Endoplasmic Reticulum / Q000378:metabolism; D007136:Immunoglobulins / Q000378:metabolism; D007248:Infertility, Male / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D013087:Spermatids / Q000166:cytology / Q000473:pathology; D013091:Spermatogenesis; D044763:Ubiquitin-Conjugating Enzymes / Q000172:deficiency / Q000378:metabolism*; D056811:Unfolded Protein Response; D015854:Up-Regulation
chemical_list: D007136:Immunoglobulins; C585487:Ube2j1 protein, mouse; D044763:Ubiquitin-Conjugating Enzymes
keywords: ER Quality Control; ERAD Tuning; Endoplasmic Reticulum-associated Protein Degradation (ERAD); Gene Knockout; Male Infertility; Mouse Model; Spermatogenesis; Spermiogenesis; Ubiquitin-conjugating Enzyme (E2 enzyme)