Role of a ubiquitin-like modification in polarized morphogenesis.
Type I ubiquitin-like proteins constitute a family of protein modifiers. Here we report the identification of a posttranslational protein modifier from Saccharomyces cerevisiae, Hub1. Overexpression of Hub1 resulted in enhanced conjugate formation when its carboxyl-terminal residue was deleted, suggesting that mature Hub1 may be produced by proteolytic processing. In vivo targets of Hub1 conjugation included cell polarity factors Sph1 and Hbt1. In the hub1Delta mutant, the subcellular localization of both Hbt1 and Sph1 was disrupted, and cell polarization during the formation of mating projections was defective. Consistent with these polarization defects, the hub1Delta mutant was deficient in mating.
Dittmar
Gunnar A G
GA
Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Wilkinson
Caroline R M
CR
Jedrzejewski
Paul T
PT
Finley
Daniel
D
D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D016764:Cell Polarity; D015180:Electrophoresis, Gel, Two-Dimensional; D017353:Gene Deletion; D005800:Genes, Fungal; D006801:Humans; D008025:Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013058:Mass Spectrometry; D000072235:Mating Factor; D008840:Microfilament Proteins; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009154:Mutation; D010455:Peptides / Q000494:pharmacology; D010641:Phenotype; D011499:Protein Processing, Post-Translational; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000235:genetics; D016415:Sequence Alignment; D013347:Subcellular Fractions / Q000378:metabolism; D025801:Ubiquitin / Q000737:chemistry / Q000378:metabolism
D008840:Microfilament Proteins; D010455:Peptides; D011993:Recombinant Fusion Proteins; C107280:SPH1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D025801:Ubiquitin; D000072235:Mating Factor; D008025:Ligases; C452202:HUB1 protein, S cerevisiae