Abstract
Myofibroblasts are unique contractile cells with both muscle and nonmuscle properties. Typically myofibroblasts are identified by the expression of smooth muscle actin (ASMA); however some myofibroblasts also express sarcomeric proteins. In this study, we show that pulmonary myofibroblasts express three of the eight known sarcomeric myosin heavy chains (MyHCs) (IIa, IId, and embryonic) and that skeletal muscle myosin enzymatic activity is required for pulmonary myofibroblast contractility. Furthermore, inhibition of skeletal myosin activity and myofibroblast contraction results in a decrease in both ASMA and skeletal MyHC promoter activity and ASMA protein expression, suggesting a potential coupling of skeletal myosin activity and ASMA expression in myofibroblast differentiation. To understand the molecular mechanisms whereby skeletal muscle genes are regulated in myofibroblasts, we have found that members of the myogenic regulatory factor family of transcription factors and Ca2+-regulated pathways are involved in skeletal MyHC promoter activity. Interestingly, the regulation of skeletal myosin expression in myofibroblasts is distinct from that observed in muscle cells and suggests that cell context is important in its control.
Disciplines
Biology | Cell Biology | Developmental Biology
Recommended Repository Citation
Rice, Nancy A. and Leinwand, Leslie A.. (2003). Skeletal Myosin Heavy Chain Function in Cultured Lung Myofibroblasts. Journal of Cell Biology, 163 (1), 119-129.
Original Publication URL: http://www.jcb.org/cgi/doi/10.1083/jcb.200303194
Available at:
https://digitalcommons.wku.edu/bio_fac_pub/2
Included in
Biology Commons, Cell Biology Commons, Developmental Biology Commons
Comments
The online version of this paper contains supplementary material. Originally published by The Rockefeller University Press, The Journal of Cell Biology, Volume 163, Number 1, October 13, 2003 119-129. http://www.jcb.org/cgi/doi/10.1083/jcb.200303194