Alpha-endosulfine
Function
Protein phosphatase inhibitor that specifically inhibits protein phosphatase 2A (PP2A) during mitosis. When phosphorylated at Ser-67 during mitosis, specifically interacts with PPP2R2D (PR55-delta) and inhibits its activity, leading to inactivation of PP2A, an essential condition to keep cyclin-B1-CDK1 activity high during M phase (By similarity). Also acts as a stimulator of insulin secretion by interacting with sulfonylurea receptor (ABCC8), thereby preventing sulfonylurea from binding to its receptor and reducing K(ATP) channel currents.
Post-translational modifications
Phosphorylation at Ser-67 by GWL during mitosis is essential for interaction with PPP2R2D (PR55-delta) and subsequent inactivation of PP2A (By similarity). Phosphorylated by PKA.
Sequence Similarities
Belongs to the endosulfine family.
Tissue Specificity
Widely expressed with high levels in skeletal muscle and brain and lower levels in the pancreas.
Cellular localization
- Cytoplasm
Alternative names
Alpha-endosulfine, ARPP-19e, ENSA