A novel AAK1 splice variant functions at multiple steps of the endocytic pathway.

ABSTRACT: Phosphorylation is a critical step in regulating receptor transport through the endocytic pathway. AAK1 is a serine/threonine kinase that is thought to coordinate the recruitment of AP-2 to receptors containing tyrosine-based internalization motifs by phosphorylating the micro2 subunit. Here we have identified a long form of AAK1 (AAK1L) that contains an extended C-terminus that encodes an additional clathrin-binding domain (CBD2) consisting of multiple low-affinity interaction motifs. Protein interaction studies demonstrate that AAK1L CBD2 directly binds clathrin. However, in vitro kinase assays reveal little difference between AAK1 isoforms in their basal or clathrin-stimulated kinase activity toward the AP-2 micro2 subunit. However, overexpression of AAK1L CBD2 impairs transferrin endoc

SUBMITTER: Henderson DM 

PROVIDER: S-EPMC1924820 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature