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bioRxiv · 10.1101/2021.12.07.471535

MYH10 governs adipocyte function and adipogenesis through its interaction with GLUT4

Abstract

Adipocyte differentiation is dependent on cytoskeletal remodeling processes that determine and maintain cellular shape and function. In turn, cytoskeletal proteins contribute to the filament-based network responsible for controlling adipocytes shape and promoting the intracellular trafficking of key cellular components. Currently, our understanding of these mechanisms remains incomplete. In this study, we identified the non-muscle myosin 10 (MYH10) as an important regulator of adipogenesis and adipocyte function through its interaction with the insulin dependent, Glucose transporter 4 (GLUT4). MYH10 depletion in preadipocytes resulted in impaired adipogenesis, with knockdown cells exhibiting disrupted morphology and reduced molecular adipogenic signals. MYH10 was shown to be in complex with GLUT4 in adipocytes, an interaction regulated by insulin induction. The missing adipogenic capacity of MYH10-KD cells was restored when they uptook GLUT4 vesicles up from neighbor wild-type cells in a co-culture system. Our results provide the first demonstration that MYH10 interacts with GLUT4 in cells and adipose tissue through the insulin pathway. The signaling cascade is regulated by the protein kinase C {zeta} (PKC{zeta}), which interacts with MYH10 to modify the localization and interaction of both GLUT4 and MYH10 in adipocytes as PKC{zeta} inhibition resulted in reduced GLUT4 and MYH10 translocation and interactions. Overall, our study establishes MYH10 as an essential regulator of GLUT4 translocation, affecting both adipogenesis and adipocyte function, highlighting its importance in future cytoskeleton-based studies in adipocytes.

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Kislev, N., Mor-Yossef Moldovan, L., Barak, R., Egozi, M., Benayahu, D.. 2021-12-07. MYH10 governs adipocyte function and adipogenesis through its interaction with GLUT4. https://doi.org/10.1101/2021.12.07.471535

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