Promoter analysis of ventricular myosin heavy chain (vmhc) in zebrafish embryos.
In zebrafish, ventricular myosin heavy chain (vmhc) gene is initially expressed at the anterior lateral mesoderm and thereafter its expression is restricted to the cardiac ventricle. The transcriptional control mechanisms in regulating chamber-specific expression of myosin heavy chains are not well defined. We isolated and analyzed zebrafish vmhc upstream region to examine the spatial and temporal regulation of vmhc using transgenic and transient expression techniques. Promoter deletion analyses defined a basal promoter region sufficient to drive vmhc expression in the ventricle and an upstream fragment necessary for repressing ectopic vmhc expression in the atrium. The transcriptional mechanism that prevents vmhc expression in the atrium is mediated through Nkx2.5 binding elements (NKE). We have further discovered that paired-related homeobox transcriptional factor 2 (Prx2/S8)-like binding elements are required for promoting vmhc expression, and Prrx1b, a Prx-related homeobox protein, participates in the regulation of vmhc expression with other transcriptional factors.
Jin
Daqing
D
The Key Laboratory of Molecular Medicine, Shanghai Medical School, Fudan University, Shanghai, China.
Ni
Terri T
TT
Hou
Jia
J
Rellinger
Eric
E
Zhong
Tao P
TP
D000818:Animals; D030801:Animals, Genetically Modified; D004625:Embryo, Nonmammalian; D018507:Gene Expression Regulation, Developmental; D049452:Green Fluorescent Proteins / Q000235:genetics; D006352:Heart Ventricles / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism / Q000502:physiology; D018995:Myosin Heavy Chains / Q000235:genetics*; D009928:Organ Specificity / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism / Q000502:physiology; D019076:Transgenes; D024723:Ventricular Myosins / Q000235:genetics*; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*; D029961:Zebrafish Proteins / Q000502:physiology
D018398:Homeodomain Proteins; D014157:Transcription Factors; D029961:Zebrafish Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D024723:Ventricular Myosins; D018995:Myosin Heavy Chains