title: Pitx2 is functionally important in the early stages of vascular smooth muscle cell differentiation.
abstract: Mechanisms that control vascular smooth muscle cell (SMC) differentiation are poorly understood. We identify Pitx2 as a previously unknown homeodomain transcription factor that is rapidly induced in an in vitro model of SMC differentiation from multipotent stem cells. Pitx2 induces expression of multiple SMC differentiation marker genes by binding to a TAATC(C/T) cis-element, by interacting with serum response factor, and by increasing histone acetylation levels within the promoters of SMC differentiation marker genes. Suppression of Pitx2 reduces expression of SMC differentiation marker genes in the early stages of SMC differentiation in vitro, whereas Prx1, another homeodomain protein, regulates SMC differentiation marker genes in fully differentiated SMCs. Pitx2, but not Prx1, knockout mouse embryos exhibit impaired induction of SMC differentiation markers in the dorsal aorta and branchial arch arteries. Our results demonstrate that Pitx2 functions to regulate the early stages of SMC differentiation.
authors.affiliation: Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908, USA.
authors.forename: Yueting
authors.initials: Y
authors.lastname: Shang
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Brad A
authors.initials: BA
authors.lastname: Amendt
authors.forename: James F
authors.initials: JF
authors.lastname: Martin
authors.forename: Gary K
authors.initials: GK
authors.lastname: Owens
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000033:anatomy & histology / Q000502:physiology; D053595:Embryonic Stem Cells / Q000166:cytology / Q000502:physiology; D005786:Gene Expression Regulation; D056464:Histone Deacetylase 2; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000502:physiology*; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D026362:Serum Response Factor / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D050880:p300-CBP Transcription Factors / Q000235:genetics / Q000378:metabolism; D000097577:Homeobox Protein PITX2; D000099224:p300-CBP-Associated Factor
chemical_list: D015415:Biomarkers; D056464:Histone Deacetylase 2; D006655:Histone Deacetylases; D006657:Histones; D018398:Homeodomain Proteins; D034741:RNA, Small Interfering; D012097:Repressor Proteins; D026362:Serum Response Factor; D014157:Transcription Factors; D050880:p300-CBP Transcription Factors; D000097577:Homeobox Protein PITX2; D000099224:p300-CBP-Associated Factor; C489936:Prrx1 protein, mouse; C533424:Hdac2 protein, mouse; C498618:Hdac5 protein, mouse