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bioRxiv · 10.1101/589754

Aurora kinase A mediated phosphorylation of mPOU is critical for skeletal muscle differentiation

Karthigeyan, D.·Bose, A.·Boopathi, R.·Rao, V. J.·Shima, H.·Bharathy, N.·Igarashi, K.·Taneja, R.·Kundu, T. K.
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Abstract

Aurora kinases are Ser/Thr-directed protein kinases which play pivotal roles in mitosis. Recent evidences highlight the importance of these kinases in non-mitotic biological events like skeletal myogenesis. Our earlier study identified POU6F1 (or mPOU) as a novel Aurora kinase A (AurkA) substrate. Here, we report that AurkA phosphorylates POU6F1 at Ser197 and inhibits its DNA binding ability. Delving into POU6F1 physiology, we find that the phospho-mimic (S197D) POU6F1 mutant exhibits enhancement, while wild type (WT) or phospho-deficient (S197A) mutant shows retardation in C2C12 myoblast differentiation. Interestingly, POU6F1 depletion phenocopies S197D-POU6F1 overexpression in the differentiation context. Collectively, our results signify mPOU as a negative regulator of skeletal muscle differentiation and strengthens the importance of AurkA in skeletal myogenesis.

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Karthigeyan, D., Bose, A., Boopathi, R., Rao, V. J., Shima, H., Bharathy, N., Igarashi, K., Taneja, R., Kundu, T. K.. 2019-03-26. Aurora kinase A mediated phosphorylation of mPOU is critical for skeletal muscle differentiation. https://doi.org/10.1101/589754

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