Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7138
pubmed:dateCreated
2007-4-19
pubmed:abstractText
The spindle checkpoint prevents chromosome mis-segregation by delaying sister chromatid separation until all chromosomes have achieved bipolar attachment to the mitotic spindle. Its operation is essential for accurate chromosome segregation, whereas its dysregulation can contribute to birth defects and tumorigenesis. The target of the spindle checkpoint is the anaphase-promoting complex (APC), a ubiquitin ligase that promotes sister chromatid separation and progression to anaphase. Using a short hairpin RNA screen targeting components of the ubiquitin-proteasome pathway in human cells, we identified the deubiquitinating enzyme USP44 (ubiquitin-specific protease 44) as a critical regulator of the spindle checkpoint. USP44 is not required for the initial recognition of unattached kinetochores and the subsequent recruitment of checkpoint components. Instead, it prevents the premature activation of the APC by stabilizing the APC-inhibitory Mad2-Cdc20 complex. USP44 deubiquitinates the APC coactivator Cdc20 both in vitro and in vivo, and thereby directly counteracts the APC-driven disassembly of Mad2-Cdc20 complexes (discussed in an accompanying paper). Our findings suggest that a dynamic balance of ubiquitination by the APC and deubiquitination by USP44 contributes to the generation of the switch-like transition controlling anaphase entry, analogous to the way that phosphorylation and dephosphorylation of Cdk1 by Wee1 and Cdc25 controls entry into mitosis.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/CDC20 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Calcium-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Cell Cycle Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/MAD2L1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Paclitaxel, http://linkedlifedata.com/resource/pubmed/chemical/Repressor Proteins, http://linkedlifedata.com/resource/pubmed/chemical/UBE2C protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin-Conjugating Enzymes, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin-Protein Ligase Complexes, http://linkedlifedata.com/resource/pubmed/chemical/anaphase-promoting complex, http://linkedlifedata.com/resource/pubmed/chemical/ubiquitin-specific protease
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1476-4687
pubmed:author
pubmed:issnType
Electronic
pubmed:day
19
pubmed:volume
446
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
876-81
pubmed:dateRevised
2011-3-11
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Anaphase initiation is regulated by antagonistic ubiquitination and deubiquitination activities.
pubmed:affiliation
Howard Hughes Medical Institute, Department of Genetics, Harvard Partners Center for Genetics and Genomics,Boston, Massachusetts 02115, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural