title: miR-145 and miR-143 regulate smooth muscle cell fate and plasticity.
abstract: MicroRNAs (miRNAs) are regulators of myriad cellular events, but evidence for a single miRNA that can efficiently differentiate multipotent stem cells into a specific lineage or regulate direct reprogramming of cells into an alternative cell fate has been elusive. Here we show that miR-145 and miR-143 are co-transcribed in multipotent murine cardiac progenitors before becoming localized to smooth muscle cells, including neural crest stem-cell-derived vascular smooth muscle cells. miR-145 and miR-143 were direct transcriptional targets of serum response factor, myocardin and Nkx2-5 (NK2 transcription factor related, locus 5) and were downregulated in injured or atherosclerotic vessels containing proliferating, less differentiated smooth muscle cells. miR-145 was necessary for myocardin-induced reprogramming of adult fibroblasts into smooth muscle cells and sufficient to induce differentiation of multipotent neural crest stem cells into vascular smooth muscle. Furthermore, miR-145 and miR-143 cooperatively targeted a network of transcription factors, including Klf4 (Kruppel-like factor 4), myocardin and Elk-1 (ELK1, member of ETS oncogene family), to promote differentiation and repress proliferation of smooth muscle cells. These findings demonstrate that miR-145 can direct the smooth muscle fate and that miR-145 and miR-143 function to regulate the quiescent versus proliferative phenotype of smooth muscle cells.
authors: Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, USA.
authors: Kimberly R
authors: KR
authors: Cordes
authors: Neil T
authors: NT
authors: Sheehy
authors: Mark P
authors: MP
authors: White
authors: Emily C
authors: EC
authors: Berry
authors: Sarah U
authors: SU
authors: Morton
authors: Alecia N
authors: AN
authors: Muth
authors: Ting-Hein
authors: TH
authors: Lee
authors: Joseph M
authors: JM
authors: Miano
authors: Kathryn N
authors: KN
authors: Ivey
authors: Deepak
authors: D
authors: Srivastava
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage; D049109:Cell Proliferation; D005260:Female; D005786:Gene Expression Regulation; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins / Q000378:metabolism; D000090062:Kruppel-Like Factor 4; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D009206:Myocardium / Q000378:metabolism; D032389:Myocytes, Smooth Muscle / Q000166:cytology* / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D014652:Vascular Diseases / Q000378:metabolism; D050808:ets-Domain Protein Elk-4 / Q000378:metabolism
chemical_list: C494194:Elk4 protein, mouse; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; C543499:MIRN145a microRNA, mouse; D035683:MicroRNAs; C532884:MIRN143 microRNA, mouse; C484469:Nkx2-5 protein, mouse; D014157:Transcription Factors; D050808:ets-Domain Protein Elk-4