RRC ID 53322
Author Gengyo-Ando K, Kage-Nakadai E, Yoshina S, Otori M, Kagawa-Nagamura Y, Nakai J, Mitani S.
Title Distinct roles of the two VPS33 proteins in the endolysosomal system in Caenorhabditis elegans.
Journal Traffic
Abstract 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.
Volume 17(11)
Pages 1197-1213
Published 2016-11-1
DOI 10.1111/tra.12430
PMID 27558849
MeSH Animals Animals, Genetically Modified Caenorhabditis elegans / genetics Caenorhabditis elegans / metabolism* Caenorhabditis elegans Proteins / genetics Caenorhabditis elegans Proteins / metabolism* Endocytosis / genetics Endocytosis / physiology* Endosomes / genetics Endosomes / metabolism* Lysosomes / genetics Lysosomes / metabolism* Male Microscopy, Confocal Mutation Oocytes / metabolism Oocytes / ultrastructure Protein Transport Spermatogenesis / genetics Spermatogenesis / physiology Spermatozoa / metabolism Spermatozoa / ultrastructure Vesicular Transport Proteins / genetics Vesicular Transport Proteins / metabolism*
IF 4.045
Times Cited 5
C.elegans tm327 tm4103 tm2608 tm4137 tm2241