Induction and modulation of smooth muscle differentiation in Xenopus embryonic cells.
By comparison with skeletal or cardiac developmental programs, little is known regarding the specific factors that promote specification and differentiation of smooth muscle cells from pluripotent cells. We have analyzed the developmental expression of a subset of smooth muscle genes during Xenopus early development and showed that similar to mammals and avians, Xenopus smooth muscle myosin heavy chain (SM-MHC) is a highly specific marker of smooth muscle differentiation. Embryonic cells from animal pole explants of Xenopus blastula can be induced by basic fibroblast growth factor, Wnt, and bone morphogenetic protein signals to adopt the smooth muscle pathway. Explants from early embryos that contain neural crest cells can also differentiate into cells expressing smooth muscle genes. We examined the interplay of several transcription factors, that is SRF, myocardin, and GATA6, that induce the expression of SM-MHC in animal cap cells and found that myocardin-dependent expression of smooth muscle genes in animal cap cells is synergized by SRF but is strongly antagonized by GATA6.
Université Bordeaux, UMR CNRS 5164, Bordeaux, France.
Wilfrid
W
Barillot
Karine
K
Tréguer
Corinne
C
Faucheux
Sandrine
S
Fédou
Nadine
N
Thézé
Pierre
P
Thiébaud
D000818:Animals; D036703:Blastula / Q000166:cytology / Q000196:embryology*; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D009130:Muscle, Smooth / Q000166:cytology / Q000378:metabolism*; D018995:Myosin Heavy Chains / Q000096:biosynthesis*; D014157:Transcription Factors / Q000378:metabolism*; D051153:Wnt Proteins / Q000378:metabolism; D014982:Xenopus laevis
D019485:Bone Morphogenetic Proteins; D014157:Transcription Factors; D051153:Wnt Proteins; D016222:Fibroblast Growth Factor 2; D018995:Myosin Heavy Chains