Linked Life Data

2500366

Source:http://linkedlifedata.com/resource/pubmed/id/2500366

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-7-28
pubmed:abstractText
Phosphorylation and dephosphorylation of proteins play an important role in the regulation of mitosis and meiosis. In our previous studies we have described mitosis-specific monoclonal antibody MPM-2 that recognizes a family of phosphopeptides in mitotic cells but not in interphase cells. These peptides are synthesized in S phase but modified by phosphorylation during G2/mitosis transition. The epitope for the MPM-2 is a phosphorylated site. In this study, we attempted to determine which amino acids are phosphorylated during the G2-mitosis (M) transition. We raised a polyclonal antibody against one of the antigens recognized by MPM-2, i.e. a protein of 55 kDa, that is present in interphase cells but modified by phosphorylation during mitosis. This antibody recognizes the p55 protein in both interphase and mitosis while it is recognized by the monoclonal antibody MPM-2 only in mitotic cells. Phosphoamino acid analysis of protein p55 from 32P-labeled S-phase and M-phase HeLa cell extracts after immunoprecipitation with anti-p55 antibodies revealed that threonine was extensively phosphorylated in p55 during G2-M but not in S phase, whereas serine was phosphorylated during both S and M phases. Tyrosine was not phosphorylated. Identical results were obtained when antigens recognized by MPM-2 were subjected to similar analysis. As cells completed mitosis and entered G1 phase phosphothreonine was completely dephosphorylated whereas phosphoserine was not. These results suggest that phosphorylation of threonine might be specific to some of the mitosis-related events.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0014-5793
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
249
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
389-95
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Threonine phosphorylation is associated with mitosis in HeLa cells.
pubmed:affiliation
Department of Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't