Linked Life Data

16257974

Source:http://linkedlifedata.com/resource/pubmed/id/16257974

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
51
pubmed:dateCreated
2005-12-19
pubmed:abstractText
The serine/threonine kinase Mirk/dyrk1B is activated in several solid tumors where it mediates cell survival, but the mechanism by which Mirk is activated in tumors is unknown. We now demonstrate that Mirk is activated as a kinase by signaling from Rac1 to the mitogen-activated protein kinase kinase MKK3. Rac is a Ras superfamily GTPase that, when activated, functions downstream of Ras oncoproteins to promote cell survival, transformation, and membrane ruffling. The constitutively active mutant Rac1QL activated Mirk in several cell types through MKK3, which in turn activated Mirk by phosphorylation. Dominant negative Rac1, dominant negative MKK3, and knockdown of MKK3 by RNA interference inhibited the kinase activity of co-expressed Mirk. E-cadherin ligation in confluent Madin-Darby canine kidney (MDCK) epithelial cells is known to transiently activate Rac1. Mirk was activated by endogenous Rac1 following E-cadherin ligation in confluent MDCK epithelial cells, whereas treatment of confluent MDCK cells with an Rac1 inhibitor decreased Mirk activity. Disruption of cadherin ligation by EGTA or prevention of cadherin ligation by maintenance of cells at subconfluent density blocked activation of Mirk. Engagement of cadherin molecules on subconfluent cells by an E-cadherin/Fc chimeric molecule transiently activated both Rac1 and Mirk with a similar time course. Rac activity is up-regulated in many human tumors and mediates survival signals, which enable tumor cells to evade apoptosis. This study characterizes a new anti-apoptotic signaling pathway that connects Rac1 with a novel downstream effector, Mirk kinase, which has recently been demonstrated to mediate survival in human tumors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
42097-105
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
The survival kinase Mirk/dyrk1B is activated through Rac1-MKK3 signaling.
pubmed:affiliation
Department of Pathology, State University of New York, Upstate Medical University, Syracuse, New York 13210, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural