荧光双分子互补分析Ezrin与L-periaxin的互作模式

腓骨肌萎缩症4F亚型是Periaxin基因的突变所导致一种脱髓鞘型遗传病. Periaxin蛋白是外周神经系统中特异且大量表达的蛋白，在髓鞘成熟与维护中发挥重要作用.而Ezrin是一种膜骨架连接蛋白，在细胞形态的维持、运动、黏附等方面发挥重要作用.在前期已证实L-periaxin与Ezrin间存在蛋白互作的基础上，本文通过分子荧光互补实验，结合免疫荧光定位实验、免疫共沉淀等技术，进一步分析并揭示了L-periaxin蛋白与Ezrin蛋白之间的互作方式，具体为L-periaxin(1 200 aa)与Ezrin(1 296 aa)以及L-periaxin (1 060～1 461 aa)与Ezrin(475～585 aa)以“头对头”与“尾对尾”的方式发生相互作用.Ezrin可能是一种引导L-periaxin在施万细胞膜上堆积的新的分子配体，二者可能通过蛋白分子间更加紧密的方式完成在细胞膜处的堆积，参与到髓鞘的维护中.

The Interaction Mode between Ezrin and L-periaxin by Bimolecular Fluorescence Complementation

Periaxin (PRX) is one of the proteins that expressed exclusively in Schwann cells. It is known as one of the key myelination molecules, forming tight junction between myelin loop and axon. As a cytoskeleton-associated protein, L-periaxin may mediate such stabilization by facilitating integration of extracellular signaling through the cytoskeleton, which is essential for changes in Schwann cell shape and regulation of gene expression during axonal ensheathment. Ezrin is a member of the ERM (Ezrin-Radxin-Moesin) protein family discovered as a cytoskeleton protein. It has been implicated in mediating actin-membrane linkage and in regulating signaling molecules. Immunofluorescence and bimolecular fluorescence complementation were performed to map the interaction between L-periaxin and Ezrin. The results indicated that interaction mode between L-periaixn and Ezrin was called “head to head and tail to tail” through the interaction between L-periaxin (1 200 aa) with Ezrin (1 296 aa), and between L-periaxin (1060-1461 aa) with Ezrin (475-585 aa). Besides DRP2 (dystrophinrelated protein 2), Ezrin is another new molecular ligand to guide the the L-periaxin accumulation on Schwann cell membrane. The interaction between L-periaxin and Ezrin may adopt the more closely form to complete protein accumulation and to participate in the maintenance of myelin sheath.