TY - JOUR T1 - Rab40c regulates focal adhesions and PP6 activity by controlling ANKRD28 ubiquitylation JF - Life Science Alliance JO - Life Sci. Alliance DO - 10.26508/lsa.202101346 VL - 5 IS - 9 SP - e202101346 AU - Ke-Jun Han AU - Valeryia Mikalayeva AU - Scott A Gerber AU - Arminja N Kettenbach AU - Vytenis A Skeberdis AU - Rytis Prekeris Y1 - 2022/09/01 UR - https://www.life-science-alliance.org/content/5/9/e202101346.abstract N2 - Rab40c is a SOCS box–containing protein which binds Cullin5 to form a ubiquitin E3 ligase complex (Rab40c/CRL5) to regulate protein ubiquitylation. However, the exact functions of Rab40c remain to be determined, and what proteins are the targets of Rab40c-Cullin5–mediated ubiquitylation in mammalian cells are unknown. Here we showed that in migrating MDA-MB-231 cells Rab40c regulates focal adhesion’s number, size, and distribution. Mechanistically, we found that Rab40c binds the protein phosphatase 6 (PP6) complex and ubiquitylates one of its subunits, ankyrin repeat domain 28 (ANKRD28), thus leading to its lysosomal degradation. Furthermore, we identified that phosphorylation of FAK and MOB1 is decreased in Rab40c knock-out cells, which may contribute to focal adhesion site regulation by Rab40c. Thus, we propose a model where Rab40c/CRL5 regulates ANKRD28 ubiquitylation and degradation, leading to a decrease in PP6 activity, which ultimately affects FAK and Hippo pathway signaling to alter focal adhesion dynamics. ER -