The functional role of ahnak in skeletal muscle fibers in an ahnak knock-out-mouse model

Ahnak是一种肌肉蛋白，可能参与质膜扩大和膜修复。拟议项目的目的是阐明ahnak在骨骼肌细胞和组织中的作用。最近，我们证明了在心肌细胞中，ahnak与l型Ca2+通道活性的调节有关，因此，兴奋-收缩耦合以及细胞的结构完整性。然而，ahnak在骨骼肌中的功能作用尚不清楚。初步结果表明，去神经支配引起的骨骼肌萎缩显著上调了ahnak的表达。因此，我们将首先通过免疫沉淀和MALDI-TOFF分析确定骨骼肌中的ahnak相互作用伙伴，特别是l型Ca2+通道和dysferltn。其次，我们将使用纯合的ahnak基因缺陷小鼠模型（小鼠后肢指短屈肌完整的单个骨骼肌纤维的收缩和细胞内Ca2+）来分析ahnak的功能作用。第三，我们将分析ahnak在正常和ahnak基因缺陷小鼠后肢固定诱导的萎缩肌肉中的功能（同时记录收缩和细胞内Ca2+）和结构（电镜）作用。

Ahnak is a muscle protein that may be involved in plasmalemma enlargement and membrane repair. The aim of the proposed project is the elucidation of ahnak's role in skeletal muscle cells and tissue. Recently, we demonstrated that in cardiomyocytes ahnak is associated with the regulation of the L-Type Ca2+ channel activity and therefore, excitation-contraction coupling, as well as the cell's structural integrity. However, the functional role of ahnak in skeletal muscle is unclear. Preliminary results suggest that skeletal muscle atrophy induced by denervation significantly upregulated ahnak expression. Therefore, we will first identify ahnak interaction partners in skeletal muscle, in particular the L-type Ca2+ channel and dysferltn, by immuno-precipitation and MALDI-TOFF analysis. Second, we will analyze the functional role of ahnak using a homozygous ahnak gene-deficient mouse model (contraction and intracellular Ca2+ in skeletal muscle registration of intact single skeletal muscle fibers from Flexor digitorum brevis of mouse hindlimb). Third, we wili analyze the functional (simultaneous registration of contraction and intracellular Ca2+) and structural (electron microscopy) role of ahnak in atrophic muscle induced by hindlimb immobilization of normal and ahnak gene-deficient mice.