Role of pre-mRNA alternative splicing programs in heart and muscle development

前信使核糖核酸选择性剪接是一种常见的方法，细胞通过它从单个基因产生多个功能不同的亚型。许多基因的发育调控剪接已经被单独描述，然而，关于选择性剪接调控程序如何有助于胚胎发育，我们知之甚少。CUG-BP和ETR-3样因子(CELF)和肌盲样蛋白(MBNL)家族的成员被证明对心脏中的Pre-mRNA选择性剪接具有拮抗性调节作用。我们假设CELF/MBNL介导的选择性剪接程序在胚胎心脏发育中发挥独立和重叠的作用。我们已经证明，在心脏形态发生过程中CELF和MBNL蛋白表达的变化伴随着选择性剪接的转变。更多的初步数据表明，CELF和/或MBNL蛋白对正常的心脏形态发生和功能至关重要。本研究的目的是阐明CELF/MBNL介导的选择性剪接程序在胚胎心脏发育中所起的作用。我们将使用鸡和小鼠模型系统来研究干扰CELF/MBNL介导的选择性剪接对心脏形态发生和功能的影响，并识别心脏中受CELF/MBNL调控的前-mRNAs亚群。了解CELF/MBNL介导的剪接程序在正常胚胎心脏发育中所起的作用，将有助于深入了解发育调控基因表达的一个未被充分研究但却很重要的机制。此外，这些研究将阐明正常选择性剪接的中断如何导致发育紊乱导致的疾病状态

Pre-mRNA alternative splicing is a common means by which cells generate multiple, functionally distinct isoforms from a single gene. Developmentally regulated splicing has been described individually for many genes, yet little is known about how programs of alternative splicing regulation contribute to embryonic development. Members of the CUG-BP and ETR-3-like factor (CELF) and muscleblind-like (MBNL) protein families have been shown to antagonistically regulate pre-mRNA alternative splicing in the heart. We hypothesize that CELF/MBNL-mediated alternative splicing programs play independent as well as overlapping roles in embryonic heart development. We have shown that changes in CELF and MBNL protein expression during cardiac morphogenesis are accompanied by transitions in alternative splicing. Additional preliminary data suggest that the CELF and/or MBNL proteins are critical for normal cardiac morphogenesis and function. The goal of this proposal is to elucidate the roles that CELF/MBNL-mediated alternative splicing programs play during embryonic heart development. We will use chicken and mouse model systems to investigate the effects of disrupting CELF/MBNL-mediated alternative splicing on cardiac morphogenesis and function, and identify the subset of pre-mRNAs subject to CELF/MBNL regulation in the heart. Understanding the roles that CELF/MBNL-mediated splicing programs play in normal embryonic heart development will provide insight into an understudied yet important mechanism of developmentally regulated gene expression. Furthermore, these studies will shed light on how disruption of normal alternative splicing contributes to disease states resulting from developmental perturbation