Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2003-7-14
pubmed:abstractText
The function of the GTPase Rac1, a molecular switch transducing intracellular signals from growth factors, in differentiation of a specific cell type during early embryogenesis has not been investigated. To address the question, we used embryonic stem (ES) cells differentiated into cardiomyocytes, a model that faithfully recapitulates early stages of cardiogenesis. Overexpression in ES cells of a constitutively active Rac (RacV12) but not of an active mutant (RacL61D38), which does not activate the NADPH oxydase generating ROS, prevented MEF2C expression and severely compromised cardiac cell differentiation. This resulted in poor expression of ventricular myosin light chain 2 (MLC2v) and its lack of insertion into sarcomeres. Thus ES-derived cardiomyocytes featured impaired myofibrillogenesis and contractility. Overexpression of MEF2C or addition of catalase in the culture medium rescued the phenotype of racV12 cells. In contrast, RacV12 specifically expressed in ES-derived ventricular cells improved the propensity of cardioblasts to differentiate into beating cardiomyocytes. This was attributed to both a facilitation of myofibrillogenesis and a prolongation in their proliferation. The dominant negative mutant RacN17 early or lately expressed in ES-derived cells prevented myofibrillogenesis and in turn beating of cardiomyocytes. We thus suggest a stage-dependent function of the GTPase during early embryogenesis.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10029572, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10030666, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10081071, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10368935, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10377168, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10438546, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10464245, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10477257, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10620813, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10653597, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10749567, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10816416, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10831115, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10836144, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10837222, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10913617, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10922488, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10928280, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-10987068, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11152757, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11266463, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11376945, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11702944, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11715034, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11923206, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-11956315, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-12094595, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-12374778, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-2440339, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-8663331, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-8663333, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-8702687, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-8999807, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9187080, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9228059, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9285711, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9308960, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9422794, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9660749, http://linkedlifedata.com/resource/pubmed/commentcorrection/12857864-9668055
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1059-1524
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2781-92
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed-meshheading:12857864-Animals, pubmed-meshheading:12857864-Cell Differentiation, pubmed-meshheading:12857864-Cells, Cultured, pubmed-meshheading:12857864-Down-Regulation, pubmed-meshheading:12857864-Gene Expression Regulation, Developmental, pubmed-meshheading:12857864-Heart, pubmed-meshheading:12857864-Mice, pubmed-meshheading:12857864-Muscle Development, pubmed-meshheading:12857864-Mutation, pubmed-meshheading:12857864-Myocytes, Cardiac, pubmed-meshheading:12857864-Myogenic Regulatory Factors, pubmed-meshheading:12857864-Myosin Light Chains, pubmed-meshheading:12857864-NADPH Oxidase, pubmed-meshheading:12857864-Rats, pubmed-meshheading:12857864-Reactive Oxygen Species, pubmed-meshheading:12857864-Sarcomeres, pubmed-meshheading:12857864-Stem Cells, pubmed-meshheading:12857864-rac1 GTP-Binding Protein
pubmed:year
2003
pubmed:articleTitle
A dual role of the GTPase Rac in cardiac differentiation of stem cells.
pubmed:affiliation
Centre de Recherches de Biochimie Macromoléculaire, CNRS FRE 2593, IFR24, Montpellier, France. puceat@crbm.cnrs-mop.fr
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't