Nud1p links astral microtubule organization and the control of exit from mitosis.
The budding yeast spindle pole body (SPB) not only organizes the astral and nuclear microtubules but is also associated with a number of cell-cycle regulators that control mitotic exit. Here, we describe that the core SPB component Nud1p is a key protein that functions in both processes. The astral microtubule organizing function of Nud1p is mediated by its interaction with the gamma-tubulin complex binding protein Spc72p. This function of Nud1p is distinct from its role in cell-cycle control: Nud1p binds the spindle checkpoint control proteins Bfa1p and Bub2p to the SPB, and is part of the mitotic exit network (MEN) in which it functions upstream of CDC15 but downstream of LTE1. In conditional lethal nud1-2 cells, the MEN component Tem1p, a GTPase, is mislocalized, whereas the kinase Cdc15p is still associated with the SPB. Thus, in nud1-2 cells the failure of Tem1p to interact with Cdc15p at the SPB probably prevents mitotic exit.
Gruneberg
U
U
The Beatson Institute for Cancer Research, CRC Beatson Laboratories, Glasgow G61 1BD, UK.
Campbell
K
K
Simpson
C
C
Grindlay
J
J
Schiebel
E
E
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000378:metabolism; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003598:Cytoskeletal Proteins; D003851:Deoxyribonucleases / Q000235:genetics / Q000502:physiology*; D005434:Flow Cytometry; D005656:Fungal Proteins / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism; D049452:Green Fluorescent Proteins; D020662:Guanine Nucleotide Exchange Factors; D007313:Insecta; D008164:Luminescent Proteins / Q000378:metabolism; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000378:metabolism*; D008938:Mitosis; D020559:Monomeric GTP-Binding Proteins / Q000378:metabolism; D009154:Mutation; D015739:Nocodazole / Q000494:pharmacology; D010641:Phenotype; D010766:Phosphorylation; D011485:Protein Binding; D029701:Saccharomyces cerevisiae Proteins; D013489:Suppression, Genetic; D013696:Temperature; D013997:Time Factors; D014404:Tubulin / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D012359:tRNA Methyltransferases
D000970:Antineoplastic Agents; C119117:BFA1 protein, S cerevisiae; C070351:BUB2 protein, S cerevisiae; C082279:CDC15 protein; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins; D020662:Guanine Nucleotide Exchange Factors; C089357:LTE1 protein, S cerevisiae; D008164:Luminescent Proteins; C102469:SPC2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C089965:TEM1 protein, S cerevisiae; D014404:Tubulin; D049452:Green Fluorescent Proteins; D012359:tRNA Methyltransferases; D003851:Deoxyribonucleases; C077501:TRM2 protein, S cerevisiae; D019204:GTP-Binding Proteins; D020559:Monomeric GTP-Binding Proteins; D015739:Nocodazole