斑马鱼因具有强大的器官再生能力而成为研究多种器官包括心脏再生的主要模式动物。本课题利用最新的Cas9/gRNA介导的条件基因敲除手段，深入研究过氧化氢信号在斑马鱼和大鼠心脏再生中的功能。第一，建立心肌细胞特异表达的CreERT2转基因斑马鱼，CreERT2转基因斑马鱼与Cas9/gRNA诱导的LoxP-floxed的gata5或其它基因突变体斑马鱼交配，产生的后代经4-OHT诱导而实现细胞特异性基因敲除。第二，我们发现gata5, gata6, dusp5和dusp6在斑马鱼心脏再生中转录活性提高，并且这种改变依赖过氧化氢信号。利用心肌或心外皮细胞条件敲除这些基因，研究它们在心脏再生中的功能和相关分子机制。第三，探索心脏再生抑制分子Dusp5和Dusp6基因敲除是否能改善大鼠心肌再生功能。研究结果将不仅开创心脏再生生物学新技术和新机制，而且为心脏再生医学发展提供理论基础。

Gaining knowledge on heart regeneration is the basis of cardiac regenerative medicine. Zebrafish becomes a powerful animal model for studying heart regeneration because it possesses incredible capacity of heart and other organ regeneration. Here we first plan to establish a new conditional knockout technology in zebrafish by applying Cas9 nuclease; then to address how hydrogen peroxide primes zebrafish heart regeneration by investigating conditional knockouts of gata5, gata6, dusp5 and dusp6; and finally to attempt at improving cardiac regenerative potential after depleting putative regenerative repressors dusp5 and/or dusp6 in rats. Our study may lead to developing conditional knockout technology in zebrafish and discovering new molecular mechanisms on adult heart regeneration, as well as laying solid foundation for new interventions and treatments in cardiac regenerative medicine.