title: γ-Tubulin plays a key role in inactivating APC/C(Cdh1) at the G(1)-S boundary.
abstract: A γ-tubulin mutation in Aspergillus nidulans, mipA-D159, causes failure of inactivation of the anaphase-promoting complex/cyclosome (APC/C) in interphase, resulting in failure of cyclin B (CB) accumulation and removal of nuclei from the cell cycle. We have investigated the role of CdhA, the A. nidulans homologue of the APC/C activator protein Cdh1, in γ-tubulin-dependent inactivation of the APC/C. CdhA was not essential, but it targeted CB for destruction in G(1), and APC/C(CdhA) had to be inactivated for the G(1)-S transition. mipA-D159 altered the localization pattern of CdhA, and deletion of the gene encoding CdhA allowed CB to accumulate in all nuclei in strains carrying mipA-D159. These data indicate that mipA-D159 causes a failure of inactivation of APC/C(CdhA) at G(1)-S, perhaps by altering its localization to the spindle pole body, and, thus, that γ-tubulin plays an important role in inactivating APC/C(CdhA) at this point in the cell cycle.
authors.affiliation: Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Edgerton-Morgan
authors.forename: Berl R
authors.initials: BR
authors.lastname: Oakley
mesh_terms: D064173:Anaphase-Promoting Complex-Cyclosome; D001233:Aspergillus nidulans / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D019926:Cyclin B / Q000235:genetics / Q000378:metabolism; D016193:G1 Phase / Q000235:genetics / Q000502:physiology*; D009154:Mutation; D016196:S Phase / Q000235:genetics / Q000502:physiology*; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism; D014404:Tubulin / Q000235:genetics / Q000378:metabolism*; D043743:Ubiquitin-Protein Ligase Complexes / Q000235:genetics / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D019926:Cyclin B; D014404:Tubulin; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome