Yoshina Sawako
   Department   School of Medicine, School of Medicine
   Position   Assistant Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Distinct roles of the two VPS33 proteins in the endolysosomal system in Caenorhabditis elegans.
Journal Formal name：Traffic (Copenhagen, Denmark)
Abbreviation：Traffic
ISSN code：(1600-0854)1398-9219(Linking)
Domestic / ForeginForegin
Volume, Issue, Page 17(11),pp.1197-1213
Author and coauthor Gengyo-Ando Keiko, Kage-Nakadai Eriko, Yoshina Sawako, Otori Muneyoshi, Kagawa-Nagamura Yuko, Nakai Junichi, Mitani Shohei
Publication date 2016/11
Summary Sec1/Munc-18 (SM) family proteins are essential regulators in intracellular transport in eukaryotic cells. The SM protein Vps33 functions as a core subunit of two tethering complexes, class C core vacuole/endosome tethering (CORVET) and homotypic fusion and vacuole protein sorting (HOPS) in the endocytic pathway in yeast. Metazoan cells possess two Vps33 proteins, VPS33A and VPS33B, but their precise roles remain unknown. Here, we present a comparative analysis of Caenorhabditis elegans null mutants for these proteins. We found that the vps-33.1 (VPS33A) mutants exhibited severe defects in both endocytic function and endolysosomal biogenesis in scavenger cells. Furthermore, vps-33.1 mutations caused endocytosis defects in other tissues, and the loss of maternal and zygotic VPS-33.1 resulted in embryonic lethality. By contrast, vps-33.2 mutants were viable but sterile, with terminally arrested spermatocytes. The spermatogenesis phenotype suggests that VPS33.2 is involved in the formation of a sperm-specific organelle. The endocytosis defect in the vps-33.1 mutant was not restored by the expression of VPS-33.2, which indicates that these proteins have nonredundant functions. Together, our data suggest that VPS-33.1 shares most of the general functions of yeast Vps33 in terms of tethering complexes in the endolysosomal system, whereas VPS-33.2 has tissue/organelle specific functions in C. elegans.
DOI 10.1111/tra.12430
PMID 27558849