lncRNA MIAT调控心脏干细胞氧化DDR的分子机制及其在心肌梗死再生修复中作用研究

To understand the mechanism for cardiac regeneration is an important task. Our study showed that MI associated long non coding RNA MIAT is specifically expressed in ckit positive cardiac progenitor cells in response to oxidative stress, and protect CPC from oxidative stress induced apoptosis and senescence. RNA binding protein FUS is a potential target of MIAT which bind to MIAT in vitro and repress oxidative stress induced DNA damage response just like MIAT. According to its functional role in DDR and our observations about FUS, we deduce that MIAT interacts with FUS and play a role in oxidative DNA damage response of CPC, therefore protect CPC from oxidative stress and benefit cardiac regeneration. To confirm the hypothesis, we will perform MI surgery and cell transduction on MIAT knockout mouses. Together with in vitro oxidative DNA damage experiments, we hope to identify the role of MIAT in CPC oxidative DDR and cardiac regeneration after MI. At the meantime,we will also perform RIP and RNA pull down assays to identify the interaction between MIAT and FUS and reveal the molecular mechanism for effect of MIAT on oxidative DNA damage response. Our project will hopefully answer the question about why CPC is not insensitive to oxidative DNA damage response and what is the mechanism for cardiac regeneration with a totally different view.

阐明梗死心肌再生修复机制是重要科学问题。本项目组前期发现：心梗相关lncRNA MIAT在ckit+CPC中特异表达，氧化应激时上调，并抑制氧化DNA损伤反应所致ckit+CPC凋亡和衰老；FUS为MIAT潜在靶分子，能够与MIAT结合，且具有与MIAT类似的抗ckit+CPC氧化应激作用。基于FUS生物学功能及项目组前期发现，我们推测：MIAT与FUS相互作用，调控ckit+CPC氧化DNA损伤反应，在MI中保护ckit+CPC、促进心肌再生修复。拟在前期实验基础上，通过基因敲除小鼠及细胞移植实验明确MIAT在ckit+CPC氧化DNA损伤及心肌再生修复中作用；采用RIP、RNA pull-down等技术阐明MIAT/FUS相互作用调控ckit+CPC氧化DDR的分子机制。本项目有望从一个新的角度阐明CPC氧化应激的调控机制，为促进梗死心肌再生修复提供新的理论和实验依据。