Hyperosmotic Stress Induces Phosphorylation of CERT and Enhances Its Tethering throughout the Endoplasmic Reticulum.

ABSTRACT: The ceramide transport protein (CERT) delivers ceramide from the endoplasmic reticulum (ER) to the Golgi apparatus, where ceramide is converted to sphingomyelin (SM). The function of CERT is regulated in two distinct phosphorylation-dependent events: multiple phosphorylations in a serine-repeat motif (SRM) and phosphorylation of serine 315 residue (S315). Pharmacological inhibition of SM biosynthesis results in an increase in SRM-dephosphorylated CERT, which serves as an activated form, and an enhanced phosphorylation of S315, which augments the binding of CERT to ER-resident VAMP-associated protein (VAP), inducing the full activation of CERT to operate at the ER-Golgi membrane contact sites (MCSs). However, it remains unclear whether the two phosphorylation-dependent regulatory events alw

SUBMITTER: Shimasaki K 

PROVIDER: S-EPMC8999913 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature