A regulatory subunit of protein phosphatase 2A, PPP2R5E, regulates the abundance of microtubule crosslinking factor 1. (October 2016)

• Record Type: Journal Article
• Authors: Hyodo, Toshinori; Ito, Satoko; Asano‐Inami, Eri; Chen, Dan; Senga, Takeshi
• Is Part Of: FEBS journal. Volume 283:Number 19(2016)
• Page Start: 3662
• Page End: 3671
• Publication Date: 2016-10
• Subjects: microtubule crosslinking factor 1 -- microtubules -- phosphatase -- PPP2R5E; Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pathology, Molecular -- Periodicals; 572
• DOI: 10.1111/febs.13835
• Languages: English
• ISSNs: 1742-464X

Abstract

Abstract : Dynamic changes in microtubule organization are regulated by numerous microtubule‐associating proteins and their post‐translational modification. Microtubule crosslinking factor 1 (MTCL1) is a recently identified protein that regulates microtubule organization. To obtain further insight into its functions, we searched for proteins that associate with it using mass spectrometry analysis. We found that PPP2R5E, a regulatory subunit of protein phosphatase 2A, interacted with MTCL1. Depletion of PPP2R5E reduced the abundance of MTCL1 abundance, whereas exogenous expression of PPP2R5E increased endogenous MTCL1. Furthermore, inhibition of phosphatase activity by okadaic acid reduced MTCL1, which was restored by the addition of the protease inhibitor MG132. Finally, we show that cells depleted of PPP2R5E and MTCL1 exhibited defects in microtubule organization. Our results suggest that the PPP2R5E phosphatase may contribute to microtubule organization by stabilizing MTCL1. Abstract : Microtubule crosslinking factor 1 (MTCL1) is essential for microtubule organization. PPP2R5E, a regulatory subunit of protein phosphatase 2A (PP2A), interacts with MTCL1. PP2A containing PPP2R5E promotes dephosphorylation of MTCL1. Dephosphorylation of MTCL1 is critical for the stabilization of MTCL1. Phosphatase‐mediated regulation of MT organization is dependent on the stabilization of MTCL1.