Genetic and biochemical interactions between an essential kinetochore protein, Cbf2p/Ndc10p, and the CDC34 ubiquitin-conjugating enzyme.
CBF2/NDC10/CTF14 encodes the 110-kDa subunit of CBF3, a key component of the yeast centromere/kinetochore. Overexpression of yeast CDC34 specifically suppresses the temperature-sensitive growth phenotype of the ndc10-1 mutation. Mutations in CDC34, which specifies a ubiquitin-conjugating enzyme, arrest yeast cells in the G1 phase of the cell cycle, with no intact spindles formed (M. G. Goebl, J. Yochem, S. Jentsch, J. P. McGrath, A. Varshavsky, and B. Byers, Science 241:1331-1335, 1988). The cdc34-2 mutation drastically alters the pattern of Cbf2p modification. Results of experiments using antibodies against Cbf2p and ubiquitin indicate that Cbf2p is ubiquitinated in vivo. Purified Cdc34p catalyzes the formation of Cbf2p-monoubiquitin conjugate in vitro. These data suggest that Cbf2p is an endogenous substrate of the CDC34 ubiquitin-conjugating enzyme and imply that ubiquitination of a kinetochore protein plays a regulatory role in kinetochore function.
Yoon
H J
HJ
Department of Biological Sciences, University of California, Santa Barbara 93106, USA.
Carbon
J
J
D064173:Anaphase-Promoting Complex-Cyclosome; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D018628:Gene Dosage; D018386:Kinetochores / Q000378:metabolism*; D008025:Ligases / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013489:Suppression, Genetic; D044763:Ubiquitin-Conjugating Enzymes; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases; D014452:Ubiquitins / Q000378:metabolism
C081071:CBF2 protein, S cerevisiae; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D014452:Ubiquitins; C577449:CDC34 protein, S cerevisiae; D044763:Ubiquitin-Conjugating Enzymes; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases