A Role for Gβγ in Regulating Golgi fragmentation

Abstract

Gβγ subunits regulate several non‐canonical functions at distinct intracellular locations. Previous work in our lab and others has established that Golgi‐localized Gβγ regulates a signaling pathway that controls the fission of protein cargo vesicles at the trans Golgi network (TGN). We recently demonstrated that Gβγ is required for mitotic Golgi fragmentation and established that knockdown or inhibition of Gβγ results in delayed mitotic progression. This study is focused on understanding the role of Gβγ in regulating Golgi fragmentation resulting from disruption of microtubules which occurs in response to drugs and disease states. We used siRNA against Gβ or specific Gγ subunits to deplete their expression, and demonstrated that their knockdown causes a significant decrease in nocodazole‐induced Golgi fragmentation. In addition, our results show that knockdown or inhibition Gβγ causes decreased activation of protein kinase D (PKD) in response to nocodazole treatment. These results implicate a role for Gβγ in regulating Golgi structure, and future experiments will help us to understand the signaling mechanisms regulated by the Gβγ subunits at the Golgi.