Sumoylation of the budding yeast kinetochore protein Ndc10 is required for Ndc10 spindle localization and regulation of anaphase spindle elongation.
Posttranslational modification by the ubiquitin-like protein SUMO (small ubiquitin-like modifier) is emerging as an important regulator in many cellular processes, including genome integrity. In this study, we show that the kinetochore proteins Ndc10, Bir1, Ndc80, and Cep3, which mediate the attachment of chromosomes to spindle microtubules, are sumoylated substrates in budding yeast. Furthermore, we show that Ndc10, Bir1, and Cep3 but not Ndc80 are desumoylated upon exposure to nocodazole, highlighting the possibility of distinct roles for sumoylation in modulating kinetochore protein function and of a potential link between the sumoylation of kinetochore proteins and mitotic checkpoint function. We find that lysine to arginine mutations that eliminate the sumoylation of Ndc10 cause chromosome instability, mislocalization of Ndc10 from the mitotic spindle, abnormal anaphase spindles, and a loss of Bir1 sumoylation. These data suggest that sumoylation of Ndc10 and other kinetochore proteins play a critical role during the mitotic process.
Montpetit
Ben
B
Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
Hazbun
Tony R
TR
Fields
Stanley
S
Hieter
Philip
P
D000705:Anaphase; D001542:Benomyl; D043171:Chromosomal Instability; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D018386:Kinetochores / Q000378:metabolism; D008239:Lysine / Q000235:genetics / Q000378:metabolism; D000072235:Mating Factor; D009154:Mutation; D015739:Nocodazole / Q000494:pharmacology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism*; D008941:Spindle Apparatus / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
C081071:CBF2 protein, S cerevisiae; C092348:CEP3 protein, S cerevisiae; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C112472:NDC80 protein, S cerevisiae; D009687:Nuclear Proteins; D010455:Peptides; D029701:Saccharomyces cerevisiae Proteins; D025841:Small Ubiquitin-Related Modifier Proteins; D000072235:Mating Factor; D008239:Lysine; D015739:Nocodazole; D001542:Benomyl