MiR-133互作lncRNAs的鉴定及协同调控牛肌肉发育分化的分子机制

Muscle development differentiation is an important topic of developmental biology. Some studies have shown that some miRNAs and lncRNAs interaction regulation the cell growth, development and differentiation, and other important life activities. MiR-133 is specifically expressed in muscle, which plays a key role in the muscle cell proliferation and differentiation, but it has not yet reported for the identification and coordinated regulation mechanism of miR-133 with interaction lncRNAs in cattle muscle development and differentiation. In previous study, we have obtained 20735 lncRNAs expressed in cattle muscle, and there were 87 lncRNAs existed complementary relationship with miR-133 in sequences, thus we suspected these 87 lncRNAs with miR-133 was likely to interaction regulate the development of cattle muscle differentiation. This project tries to screening and identified the lncRNAs interaction with miR-133 based on these 87 lncRNAs, and then further study the molecular mechanism of these lncRNAs with miR-133 interaction regulate cattle muscle development. It can provide a new ideas and useful clues for the study of muscle physiological mechanism and molecular traits improvement in beef cattle.

肌肉发育分化是发育生物学研究的重要主题。现有的研究已表明，一些miRNAs能够和lncRNAs互作协同调控细胞的生长、发育及分化等重要生命活动。miR-133是肌肉发育特异表达的miRNAs，并且在肌细胞增殖与分化中发挥着关键性的调控作用，而有关与miR-133互作的牛肌肉发育相关lncRNAs的鉴定及协同调控肌肉生长发育分化的研究至今未见报道。在前期研究中我们获得了20735 条牛肌肉组织表达的lncRNAs，并发现有87条lncRNAs在序列上与牛肌肉发育特异性表达miR-133存在互补关系，据此推断这87条lncRNAs很可能与miR-133协同调控牛肌肉的发育分化。本项目拟以这87条lncRNAs为基础，筛选、鉴定出与miR-133存在互作的lncRNAs，然后深入研究这些lncRNAs与miR-133互作调控牛肌肉发育的分子机制，旨在为肉牛的分子改良设计奠定基础性研究。

miRNAs和lncRNAs都属于非编码RNA，它们在细胞的生命活动中都起着重要的调控作用。众多研究表明，许多miRNAs能和lncRNAs互作调控细胞的生长发育和分化。miR-133已被证明是肌肉特异性表达的miRNAs，能够在肌细胞增殖与分化中发挥关键性的调控作用。实验室前期利用高通量测序技术对牛的肌肉组织进行了测序，经生物信息学深度分析后，发现有87条lncRNAs在序列上与牛肌肉特异性表达miR-133存在互补关系，据此推断这87条lncRNAs中很可能存在与miR-133互作协同调控牛肌肉发育分化的lncRNAs，本项目即以这87条lncRNAs为基础，开展筛选、鉴定与miR-133存在互作的lncRNAs，并深入研究这些lncRNAs与miR-133互作协同调控牛肌肉发育的分子机制。通过利用分子生物学和细胞生物学的技术手段，鉴定出2个与miR-133互作的牛肌肉发育相关lncRNAs，其中miR-133b与lnc133b存在互作，miR-133a与lnc133a存在互作。进一步利用牛肌细胞模型，开展了miR-133b与lnc133b以及miR-133a与lnc133a协同调控牛肌细胞增值与分化的功能研究。经实验验证并结合众多资料报道，发现lnc133b参与牛肌卫星细胞发育的调控可能是通过lnc133b/miR-133b/ FGFR1＆PP2AC和lnc133b/miR-133b/ IGF1R通路实现的；lnc133a参与牛肌卫星细胞发育的调控可能是通过lnc133a/miR-133a/LASP1和lnc133a/miR-133a/ IGF1R通路实现的。本项目的完成为miR-133与互作lncRNAs协同调控牛肌肉发育分化的机制积累了基础资料，在理论上加深了对肌肉发育生长分子遗传基础的认识，同时也为研究肉牛肌肉发育的生理机制、肉牛性状的分子改良提供了重要的研究靶标和有益线索。