A putative GTP binding protein homologous to interferon-inducible Mx proteins performs an essential function in yeast protein sorting.
Members of the Mx protein family promote interferon-inducible resistance to viral infection in mammals and act by unknown mechanisms. We identified an Mx-like protein in yeast and present genetic evidence for its cellular function. This protein, the VPS1 product, is essential for vacuolar protein sorting, normal organization of intracellular membranes, and growth at high temperature, implying that Mx-like proteins are engaged in fundamental cellular processes in eukaryotes. Vps1p contains a tripartite GTP binding motif, which suggests that binding to GTP is essential to its role in protein sorting. Vps1p-specific antibody labels punctate cytoplasmic structures that condense to larger structures in a Golgi-accumulating sec7 mutant; thus, Vps1p may associate with an intermediate organelle of the secretory pathway.
Rothman
J H
JH
Institute of Molecular Biology, University of Oregon, Eugene 97403.
Raymond
C K
CK
Gilbert
T
T
O'Hara
P J
PJ
Stevens
T H
TH
D000595:Amino Acid Sequence; D000818:Animals; D000998:Antiviral Agents / Q000235:genetics; D001483:Base Sequence; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D005455:Fluorescent Antibody Technique; D019204:GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005838:Genotype; D015151:Immunoblotting; D008969:Molecular Sequence Data; D009154:Mutation; D064547:Myxovirus Resistance Proteins; D014176:Protein Biosynthesis; D011499:Protein Processing, Post-Translational; D011506:Proteins / Q000235:genetics*; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014714:Vertebrates; D033921:Vesicular Transport Proteins
D000998:Antiviral Agents; D002352:Carrier Proteins; D064547:Myxovirus Resistance Proteins; D011506:Proteins; D033921:Vesicular Transport Proteins; D019204:GTP-Binding Proteins; C064553:VPS1 protein, S cerevisiae