NexilinRegulates Rat Ventricular Cardiomyocyte Contractility via Sarcomere Arrangement
Wang Lin, Wang Hui, Shi Xiao Lu, Song Li, YeJue, Xu Rui Xia, Zhang Yan Wan, Meng Xian Min

Nexilin, an F-actin binding protein, localized at Z-disk in cardiomyocytes. Mutations on nexilinare related to hypertrophic cardiomyopathy characterized by impaired contraction. Here, we investigated the relationship between nexilin and cell contractility innormal or hypertrophic cardiomyocytes. In this study, we found that nexilin was upregulated in hypertrophic cardiomyocytes. To investigate nexilin functional role in cardiomyocyte, adenovirus carrying full length cDNA of nexilin or green fluorescence protein or shRNA target to nexilin were generated and expressed in cardiomyocytes. We found that contractility of hypertrophic cardiomyocytes increased compared with normal cardiomyocytes; Contractility of normal cardiomyocytes with Nexilin overexpression showed the similar results with that of hypertrophic cardiomyocytes. Nexilin knockdown in hypertrophic cardiomyocytes decreased contractility with disordered sarcomere. More over, through staining ofactin filament, we found that hypertrophic cardiomyocytes and nexilin over expression cardiomyocytes maintain normal sarcomere arrangement. On the contrary, nexilin knockdown disordered the sarcomere arrangement of hypertrophic cardiomyocyte and normal cardiomyocytes. These results demonstrated that nexilin is essential for cardiomyocyte sarcomere arrangement and contractility regulation. nexilin was involved in cardiac hypertrophy progress.

Full Text: PDF     DOI: 10.15640/aijb.v3n1a6