Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
|
pubmed:dateCreated |
1993-11-19
|
pubmed:abstractText |
Mitogen-activated protein kinase (MAP kinase) is a serine/threonine kinase whose enzymatic activity is thought to play a crucial role in mitogenic signal transduction and also in the progesterone-induced meiotic maturation of Xenopus oocytes. We have purified MAP kinase from Xenopus oocytes and have shown that the protein is present in metaphase II oocytes under two different forms: an inactive 41-kD protein able to autoactivate and to autophosphorylate in vitro, and an active 42-kD kinase resolved into two tyrosine phosphorylated isoforms on 2D gels. During meiotic maturation, MAP kinase becomes tyrosine phosphorylated and activated following the activation of the M-phase promoting factor (MPF), a complex between the p34cdc2 kinase and cyclin B. In vivo, MAP kinase activity displays a different stability in metaphase I and in metaphase II: protein synthesis is required to maintain MAP kinase activity in metaphase I but not in metaphase II oocytes. Injection of either MPF or cyclin B into prophase oocytes promotes tyrosine phosphorylation of MAP kinase, indicating that its activation is a downstream event of MPF activation. In contrast, injection of okadaic acid, which induces in vivo MPF activation, promotes only a very weak tyrosine phosphorylation of MAP kinase, suggesting that effectors other than MPF are required for the MAP kinase activation. Moreover, in the absence of protein synthesis, cyclin B and MPF are unable to promote in vivo activation of MAP kinase, indicating that this activation requires the synthesis of new protein(s).
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Ethers, Cyclic,
http://linkedlifedata.com/resource/pubmed/chemical/Maturation-Promoting Factor,
http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase 1,
http://linkedlifedata.com/resource/pubmed/chemical/Okadaic Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Protein-Serine-Threonine Kinases,
http://linkedlifedata.com/resource/pubmed/chemical/Protein-Tyrosine Kinases,
http://linkedlifedata.com/resource/pubmed/chemical/Tyrosine
|
pubmed:status |
MEDLINE
|
pubmed:month |
Sep
|
pubmed:issn |
1040-452X
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
36
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
96-105
|
pubmed:dateRevised |
2009-11-19
|
pubmed:meshHeading |
pubmed-meshheading:8398135-Animals,
pubmed-meshheading:8398135-Enzyme Activation,
pubmed-meshheading:8398135-Ethers, Cyclic,
pubmed-meshheading:8398135-Female,
pubmed-meshheading:8398135-Maturation-Promoting Factor,
pubmed-meshheading:8398135-Mitogen-Activated Protein Kinase 1,
pubmed-meshheading:8398135-Okadaic Acid,
pubmed-meshheading:8398135-Oocytes,
pubmed-meshheading:8398135-Phosphorylation,
pubmed-meshheading:8398135-Protein Biosynthesis,
pubmed-meshheading:8398135-Protein-Serine-Threonine Kinases,
pubmed-meshheading:8398135-Protein-Tyrosine Kinases,
pubmed-meshheading:8398135-Tyrosine,
pubmed-meshheading:8398135-Xenopus laevis
|
pubmed:year |
1993
|
pubmed:articleTitle |
Mitogen-activated protein kinase (MAP kinase) activation in Xenopus oocytes: roles of MPF and protein synthesis.
|
pubmed:affiliation |
INRA/URA CNRS 1449, Université P. et M. Curie, Paris, France.
|
pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
|