鸭MyoG基因编码区的克隆及其在鸭心肌组织发育中的表达研究

肌细胞生成素(myogenin,MyoG)在胚胎发育中发挥作用,并能与在心脏发育过程中起重要作用的MEF2基因家族协同促进肌肉的分化,而其在心肌发育中的作用却鲜有报道。为研究其在胚胎心肌组织发育过程中的作用,本研究扩增了鸭MyoG基因CDS序列,并采用实时荧光定量PCR法检测了MyoG在鸭E10、E14、E18、E22、E27 d及出生后1周雏鸭(P7 d)心肌组织中共6个阶段的表达变化。基因扩增得到鸭MyoG基因CDS序列共684bp,编码227个氨基酸,预测其含有碱性螺旋-环-螺旋(bHLH)结构域。结果表明:MyoG在鸭E10 d中的表达量最高,显著高于E14、E18、E22和E27 d(P0.05);E14 d与E18 d,E22 d和E27 d之间的表达差异不显著(P0.05);MyoG在鸭出壳前心肌组织中的表达量整体呈现下降趋势,出生后1周,表达量又明显上升,与E22 d和E27 d差异显著(P0.05)。MyoG在鸭心肌组织的发育中起作用,其机理可能是通过MyoG的bHLH结构域直接或以MEF2基因家族介导间接实现对心脏发育的调控。

Cloning of Duck MyoG Gene Coding Domain Sequence and Its Developmental Expression in Duck Heart Tissues

Myogenin(MyoG) plays a key role during embryogenesis and it can regulate the muscle differentiation when cooperating with the myocyte enhancer factor2(MEF2) gene family,which has an important function in the heart development.But the roles of MyoG in the myocardium development and differentiation were seldom elucidated so far.In order to investigate the roles of MyoG in duck heart tissues,the coding domain sequence of duck MyoG was cloned,and the relative mRNA expression of MyoG during embryogenesis stages on E10,E14,E18,E22,E27d and postnatal 7 d were detected using real-time PCR method.The sequence analyze results showed that the coding domain sequence of duck MyoG consists of 684 nucleotides and codes for 227 AA,including the bHLH domain.The results of the real-time PCR indicate that it has an expression in each stage,and the mRNA expression level on E10 d was higher than that of any other stages(P < 0.05).After this period,the expression level decreased until born,and then increased postnatal,which was significantly higher than that of prenatal stages(P < 0.05).There was no significant difference on the stages on E14,E18,E22 and E27d(P > 0.05).MyoG has an effect on heart development and the regulation mechanisms may be through its bHLH domain directly or mediated by MEF2 gene family indirectly.