Molecular Mechanism of Akirin Function During Myogenesis

描述（申请人提供）：成肌细胞在肌源性转录因子作用下的特化和分化是骨骼肌组织形成的关键事件。在胚胎肌肉发育之后，成肌细胞的特化和分化对于哺乳动物健康成年肌肉的维持和再生仍然是必不可少的。不能通过建立新的成肌细胞群体来适当地维持肌肉稳态导致进行性退行性肌肉萎缩。然而，尽管成肌细胞的特化和分化对肌发生至关重要，但在这一过程中新分子的身份仍然未知。对果蝇（Drosophila melanogaster）的初步研究最近发现了一种新的肌发生参与者， 保守的核蛋白Akirin。Akirin似乎在成肌细胞特化过程中的基因表达调控中发挥重要但尚未确定的作用。本提案的总体目标是利用果蝇来鉴定和表征肌发生过程中Akirin基因调控的分子机制。这项研究的基本原理是，通过了解Akirin等新型肌生成调节剂的作用模式，可以提高旨在减轻或逆转肌肉萎缩的治疗效果。我们将通过两个具体目标来研究Akirin的行动模式。首先，我们将进行缺失分析，以确定Akirin和转录机制之间的相互作用域，这对Akirin介导的基因调控至关重要。其次，我们将使用双杂合子测定来鉴定在肌肉发育期间与Akirin相互作用的候选蛋白，并且是Akirin介导的基因调控的必要辅因子。重要的是，为了与AREA奖励机制的目标保持一致，该项目将为本科研究人员提供各种分子，遗传和生物化学技术的实践经验，这将为未来的生物医学研究职业提供宝贵的技能。

DESCRIPTION (provided by applicant): The specification and differentiation of myoblasts by the action of myogenic transcription factors is a key event in the formation of the skeletal musculature. Following embryonic muscle development, the specification and differentiation of myoblasts remains essential for the maintenance and regeneration of healthy adult muscle in mammals. Failure to maintain muscle homeostasis properly through the establishment of new populations of myoblasts leads to progressive degenerative muscle wasting. However, despite the primary importance of myoblast specification and differentiation for myogenesis, the identities of new molecular players in this process remain unknown. Preliminary studies in the fruit fly, Drosophila melanogaster, have recently identified a novel participant in myogenesis, the conserved nuclear protein Akirin. Akirin appears to play an important yet still unidentified role i the regulation of gene expression during myoblast specification. The overall goal of this proposal is to use Drosophila to identify and characterize the molecular mechanism of gene regulation by Akirin during myogenesis. The rationale for the proposed research is that through understanding the modes of action of novel regulators of myogenesis such as Akirin, the efficacy of therapies aimed at mitigating or reversing muscle wasting can be improved. We will study Akirin's mode of action through two specific aims. First, we will perform deletion analysis to identify the domains of interaction between Akirin and the transcriptional machinery that are critical for Akirin-mediated gene regulation. Second, we will use a double heterozygote assay to identify candidate proteins that interact with Akirin during muscle development, and are essential cofactors for Akirin-mediated gene regulation. Critically, in keeping with the goals of the AREA award mechanism, this project will give undergraduate researchers hands-on experience in a wide variety of molecular, genetic and biochemical techniques, which will provide a valuable skill set for a future career in biomedical research.