Lv Feng, Zhu Chenwen, Yan Xinghong, Wang Xin, Liu Dong
College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Lingang New City, Shanghai, 201306, China.
Nantong Science and Technology College, Qingnian Middle Road 136, Nantong, 226006, China.
Fish Physiol Biochem. 2017 Feb;43(1):287-294. doi: 10.1007/s10695-016-0286-3. Epub 2016 Sep 8.
Transgenesis is an important tool for exploring gene expression and function. The myocyte enhancer factor 2a (mef2a) gene encodes a member of the Mef2 protein family that is involved in vertebrate skeletal, cardiac, and smooth muscle development and differentiation during myogenesis. According to studies on human and animal models, mef2a is highly expressed in the heart and somites. To explore the potential of mef2a as a tool for selective labeling of muscle cells in living zebrafish embryos, we constructed a transgene mef2aa:EGFP to induce the expression of green fluorescent protein (GFP) under the control of mef2a promoter. A ~2-kb DNA fragment, upstream of the translational start site of mef2aa, was identified to drive muscle-specific expression of EGFP in zebrafish embryos. Interestingly, the cranial muscles, abductor muscle, and adductor muscle were clearly labeled with EGFP in the established line Tg(mef2aa:EGFP) . In addition, we showed that mef2aa mRNA was highly present in adult zebrafish heart, but not the skeleton muscle, whereas it was expressed in both embryonic heart and myotome, suggesting that mef2a is vital to the function of adult heart in vertebrates.
转基因技术是探索基因表达和功能的重要工具。肌细胞增强因子2a（mef2a）基因编码Mef2蛋白家族的一个成员，该家族参与脊椎动物在肌生成过程中的骨骼肌、心肌和平滑肌的发育与分化。根据对人类和动物模型的研究，mef2a在心脏和体节中高度表达。为了探索mef2a作为在活体斑马鱼胚胎中选择性标记肌肉细胞工具的潜力，我们构建了转基因mef2aa:EGFP，以在mef2a启动子的控制下诱导绿色荧光蛋白（GFP）的表达。在mef2aa翻译起始位点上游鉴定出一个约2 kb的DNA片段，可驱动斑马鱼胚胎中EGFP的肌肉特异性表达。有趣的是，在已建立的Tg(mef2aa:EGFP)品系中，颅肌、外展肌和内收肌都被EGFP清晰地标记。此外，我们发现mef2aa mRNA在成年斑马鱼心脏中高度存在，但在骨骼肌中不存在，而它在胚胎心脏和肌节中均有表达，这表明mef2a对脊椎动物成年心脏的功能至关重要。
