Mitotic exit regulation through distinct domains within the protein kinase Cdc15.
The mitotic exit network (MEN), a Ras-like signaling cascade, promotes the release of the protein phosphatase Cdc14 from the nucleolus and is essential for cells to exit from mitosis in Saccharomyces cerevisiae. We have characterized the functional domains of one of the MEN components, the protein kinase Cdc15, and investigated the role of these domains in mitotic exit. We show that a region adjacent to Cdc15's kinase domain is required for self-association and for binding to spindle pole bodies and that this domain is essential for CDC15 function. Furthermore, we find that overexpression of CDC15 lacking the C-terminal 224 amino acids results in hyperactivation of MEN and premature release of Cdc14 from the nucleolus, suggesting that this domain within Cdc15 functions to inhibit MEN signaling. Our findings indicate that multiple modes of MEN regulation occur through the protein kinase Cdc15.
Bardin
Allison J
AJ
Center for Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Boselli
Monica G
MG
Amon
Angelika
A
D001665:Binding Sites; D002453:Cell Cycle / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002466:Cell Nucleolus / Q000235:genetics / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008938:Mitosis; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D017434:Protein Structure, Tertiary / Q000502:physiology; D021381:Protein Transport / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism; D013692:Telophase / Q000235:genetics
C082279:CDC15 protein; D018797:Cell Cycle Proteins; D008164:Luminescent Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; C089965:TEM1 protein, S cerevisiae; D049452:Green Fluorescent Proteins; D011494:Protein Kinases; C085768:DBF2 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; D019204:GTP-Binding Proteins; D020559:Monomeric GTP-Binding Proteins