Affiliation:
1. Department of Medicine, University of Vermont College of Medicine, Burlington.
Abstract
The sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2) plays a critical role in the contractile performance of cardiac and slow-twitch skeletal muscle by restoring cytosolic calcium to low resting levels during the contractile cycle. We have previously shown that SERCA2 expression in the heart is altered by a number of pathophysiological stimuli. In an effort to define molecular mechanisms regulating expression of the SERCA2 gene in cardiac muscle cells, deletions of a 1460-bp promoter fragment were generated and inserted into a luciferase reporter plasmid. Promoter constructs were transiently transfected into embryonic cardiocytes and skeletal muscle cell lines Sol 8 and C2C12 in vitro and injected into adult myocardium in vivo. Results demonstrate that sequences from the transcription start site to -284 are both necessary and sufficient for high-level transcription of the reporter gene in differentiating muscle cells and in fetal cardiocytes in culture. We further demonstrate that this promoter fragment is highly active in vivo when injected into rat hearts, suggesting that the same regulatory elements are functional in vivo as well as in vitro. The region of the gene from -284 to -658 exerts a modest positive effect in cardiocytes and Sol 8 myotubes but exerts a negative effect in C2C12 fast skeletal muscle cells. This initial analysis of transcriptional regulation of the SERCA2 gene will serve as a foundation for the study of alterations of expression of the gene in pathological conditions.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Cardiology and Cardiovascular Medicine,Physiology
Reference40 articles.
1. Lytton J MacLennan DH. Sarcoplasmic reticulum. In: Fozzard HA Haber E Jennings RB Katz AM Morgan HE eds. The Heart and Cardiovascular System. New York NY: Raven Press Publishers; 1992:1203-1223.
2. Regulation of myocardial Ca2+-ATPase and phospholamban mRNA expression in response to pressure overload and thyroid hormone.
3. Thyroid hormone markedly increases the mRNA coding for sarcoplasmic reticulum Ca-ATPase in the rat heart;Rohrer D;J Biol Chem.,1988
Cited by
28 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献