| First Author | Samaha FF | Year | 1996 |
| Journal | J Biol Chem | Volume | 271 |
| Issue | 1 | Pages | 395-403 |
| PubMed ID | 8550594 | Mgi Jnum | J:30533 |
| Mgi Id | MGI:78040 | Doi | 10.1074/jbc.271.1.395 |
| Citation | Samaha FF, et al. (1996) Developmental pattern of expression and genomic organization of the calponin-h1 gene. A contractile smooth muscle cell marker. J Biol Chem 271(1):395-403 |
| abstractText | Calponin-h1 is a 34-kDa myofibrillar thin filament, actin-binding protein that is expressed exclusively in smooth muscle cells (SMCs) in adult animals. To examine the molecular mechanisms that regulate SMC-specific gene expression, we have examined the temporal, spatial, and cell cycle-regulated patterns of expression of calponin-h1 gene expression and isolated and structurally characterized the murine calponin-h1 gene. Calponin-h1 mRNA is expressed exclusively in SMC-containing tissues in adult animals. During murine embryonic development, calponin-h1 gene expression is (i) detectable in E9.5 embryos in the dorsal aorta, cardiac outflow tract, and tubular heart, (ii) sequentially up-regulated in SMC-containing tissues, and (iii) down-regulated to non-detectable levels in the heart during late fetal development. In addition, the gene is expressed in resting rat aortic SMCs, but its expression is rapidly down-regulated when growth-arrested cells reenter phase G1 of the cell cycle and proliferate. Calponin-h1 is encoded by a 10.7-kilobase single copy gene composed of seven exons, which is part of a multigene family. Transient transfection analyses demonstrated that 1.5 kilobases of calponin-h1 5'-flanking sequence is sufficient to program high level transcription of a luciferase reporter gene in cultured primary rat aortic SMCs and the smooth muscle cell line, A7r5. Taken together, these data suggest that the calponin-h1 gene will serve as an excellent model system with which to examine the molecular mechanisms that regulate SMC lineage specification, differentiation, and phenotypic modulation. |
