Rb and LEK1: a "pas de deux" in cardiogenesis.
Cardiogenesis results from activation of a complex transcriptional network. The transcription factors work in a combinatorial manner to transactivate expression of constitutive genes. Embryonic stem (ES) cells are capable to recapitulate the early stages of cardiac cell differentiation. So far only the Bone Morphogenetic Protein (BMP)-dependent pathway switching on expression of Nkx2.5, one of the earliest cardiac transcription factor, has been described as the canonical cardiogenic pathway. Recently, using Rb-/- and LEK1-downregulated ES cells, we described a novel BMP-independent cardiogenic pathway implicating both Rb and LEK1, a mammalian homolog of the chicken cardiomyogenic factor 1(CMF1). Here, I discuss the role of Rb pathways in cell differentiation and the potential mechanisms underlying the effect of Rb/LEK1 interaction on cardiac specification of stem cells.
Pucéat
Michel
M
CRBM, CNRS FRE 2593; 1919 Route de Mende, Montpellier 34293 France. michel.puceat@crbm.cnrs.fr
D000818:Animals; D030161:Avian Proteins / Q000378:metabolism; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D002454:Cell Differentiation; D049109:Cell Proliferation; D002645:Chickens; D002843:Chromatin / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism / Q000502:physiology*; D015536:Down-Regulation; D004622:Embryo, Mammalian / Q000166:cytology; D004625:Embryo, Nonmammalian; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D008840:Microfilament Proteins; D009124:Muscle Proteins / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D019076:Transgenes; D029867:Xenopus Proteins / Q000378:metabolism
D030161:Avian Proteins; D019485:Bone Morphogenetic Proteins; D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins; D008840:Microfilament Proteins; D009124:Muscle Proteins; C092720:NKX2-5 protein, Xenopus; D016160:Retinoblastoma Protein; D014157:Transcription Factors; D029867:Xenopus Proteins; C101539:cardiac muscle factor 1 protein, chicken; C094772:centromere protein F