The cytoplasmic domain of the polymeric immunoglobulin receptor contains two internalization signals that are distinct from its basolateral sorting signal.

Abstract

The C-terminal cytoplasmic domain of the polymeric immunoglobulin receptor (pIgR) contains two tyrosine residues, Tyraes and Tyr734.Previous work identifying T Y ~' ' ~ as a critical residue in the endocytosis of the pIgR in Madin-Darby canine kidney (MDCK) cells also suggested that a second functional internalization signal was present (Breitfeld, P.