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. 2019 Jul;120(7):11284-11304.
doi: 10.1002/jcb.28406. Epub 2019 Feb 11.

Role of Akirin1 in the regulation of skeletal muscle fiber-type switch

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Role of Akirin1 in the regulation of skeletal muscle fiber-type switch

Vanitha Venkoba Rao et al. J Cell Biochem. 2019 Jul.

Abstract

Akirin1 is a highly conserved ubiquitously expressed nuclear protein. Owing to its strong nuclear localization signal and protein-protein interaction properties, Akirin1 has been speculated to regulate transcription of target genes as a cofactor. Previous studies have reported Akirin1 as a downstream target of myostatin, a potent negative regulator of myogenesis. Mice lacking myostatin displayed enhanced Akirin1 gene expression. Further, in vitro evidence has shown Akirin1 overexpression leads to hypertrophy in C2 C 12 myotubes. In this study, we used Akirin1 knockout mice as a model system to further elucidate the function of Akirin1 in fully differentiated skeletal muscle. Akirin1 knockout mice did not show any obvious phenotypic difference when compared with wild type. However, promoter-reporter assay suggested that Akirin1 regulated the transcription of muscle-specific RING finger 1 (MuRF-1), an important E3 ubiquitin ligase in skeletal muscle. Furthermore, ablation of Akirin1 resulted in increased type IIa and decreased type I muscle fibers, which was further supported by an increase in Myh2 and decrease in Myh7 gene expression. Also, histochemical studies for succinate dehydrogenase activity revealed a less oxidative muscle in the absence of Akirin1. Together, our study suggests a novel role of Akirin1 in maintaining the muscle fiber type and regulation of the metabolic activity of the skeletal muscle.

Keywords: Akirin1; atrogenes; fiber-type switch; muscle ring finger 1; myosin heavy chains; sarcomere; skeletal muscle.

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References

REFERENCES
    1. Lompre AM, Nadal-Ginard B, Mahdavi V. Expression of the cardiac ventricular alpha- and beta-myosin heavy chain genes is developmentally and hormonally regulated. J Biol Chem. 1984;259(10):6437-6446.
    1. Talmadge RJ, Roy RR, Edgerton RV. Muscle fiber types and function. Curr Opin Rheumatol. 1993;5(6):695-705.
    1. Seeley M, Huang W, Chen Z, Wolff WO, Lin X, Xu X. Depletion of zebrafish titin reduces cardiac contractility by disrupting the assembly of Z-discs and A-bands. Circ Res. 2007;100(2):238-245. https://doi.org/10.1161/01.RES.0000255758.69821.b5
    1. Jagoe RT, Goldberg AL. What do we really know about the ubiquitin-proteasome pathway in muscle atrophy? Curr Opin Clin Nutr Metab Care. 2001;4(3):183-190.
    1. Pizon V, Iakovenko A, Van Der Ven PF, et al. Transient association of titin and myosin with microtubules in nascent myofibrils directed by the MURF2 RING-finger protein. J Cell Sci. 2002;115(Pt 23):4469-4482.

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