Transthyretin Is a Key Regulator of Myoblast Differentiation

• DOI: 10.1371/journal.pone.0063627
• Publication Date: 2013-05-22T22:31:34Z
• Authors: Eun Ju Lee; Abdul R. Bhat; Majid Rasool Kamli; Smritee Pokharel; Tahoon Chun; Yong-Ho Lee; Sang-Seop Nahm; Joo Hyun Nam; Seong Koo Hong; Bohsuk Yang; Ki Young Chung; Sang Hoon Kim; Inho Choi
• Keywords: Male; 0301 basic medicine; Science; Q; Muscle Fibers, Skeletal; R; Gene Expression; Cell Differentiation; Muscle Development; Cell Line; Up-Regulation; Mice, Inbred C57BL; Myoblasts; Mice; 03 medical and health sciences; Medicine; Animals; Prealbumin; Myogenin; Calcium Channels; Muscle, Skeletal; Research Article

Transthyretin (TTR) is a known carrier protein for thyroxine (T4) and retinol-binding protein in the blood that is primarily synthesized in the liver and choroid plexus of the brain. Herein, we report that the TTR gene is expressed in skeletal muscle tissue and up-regulated during myotube formation in C2C12 cells. TTR silencing (TTRkd) significantly reduced myogenin expression and myotube formation, whereas myogenin silencing (MYOGkd) did not have any effect on TTR gene expression. Both TTRkd and MYOGkd led to a decrease in calcium channel related genes including Cav1.1, STIM1 and Orai1. A significant decrease in intracellular T4 uptake during myogenesis was observed in TTRkd cells. Taken together, the results of this study suggest that TTR initiates myoblast differentiation via affecting expression of the genes involved during early stage of myogenesis and the genes related to calcium channel.