{mu}-Crystallin controls muscle function through thyroid hormone action [Research Communication]

In this study, Crym was preferentially expressed in skeletal muscle throughout the body. Crym-knockout mice exhibited a significant hypertrophy of fast-twitch glycolytic type IIb fibers, causing an increase in grip strength and high intensity running ability in Crym-null mice. Genetic inactivation of Crym or blockade of Crym by siRNA-mediated knockdown up-regulated the gene expression of fast-glycolytic contractile fibers in satellite cell-derived myotubes in vitro. These alterations in Crym-inactivated muscle were rescued by inhibition of thyroid hormone, even though Crym is a positive regulator of thyroid hormone action in nonmuscle cells. The results demonstrated that Crym is a crucial regulator of muscle plasticity, controlling metabolic and contractile properties of myofibers, and thus the selective inactivation of Crym may be a potential therapeutic target for muscle-wasting diseases, such as muscular dystrophies and age-related sarcopenia.—Seko, D., Ogawa, S., Li, T.-S., Taimura, A., Ono, Y. μ-Crystallin controls muscle function through thyroid hormone action.
Source: FASEB Journal - Category: Biology Authors: Tags: Research Communication Source Type: research