Faculty Collaboration Database

Basolateral sorting signal of the 300-kDa mannose 6-phosphate receptor. Am J Physiol Gastrointest Liver Physiol 2002 Jan;282(1):G51-60

Date

12/26/2001

Pubmed ID

11751157

DOI

10.1152/ajpgi.00028.2001

Scopus ID

2-s2.0-0036080409 (requires institutional sign-in at Scopus site)   10 Citations

Abstract

In polarized cells, the delivery of numerous membrane proteins from the trans-Golgi network to the basolateral surface depends on specific sequences located in their cytoplasmic domain. We have previously shown that the insulin-like growth factor-II/mannose 6-phosphate receptor (IGF-II/MPR) exhibits a polarized cell surface distribution in the human colon adenocarcinoma (Caco-2) cell line in which there is a threefold enrichment on the basolateral surface. To investigate the role of residues in the cytoplasmic region of the receptor that facilitates its entry into the basolateral sorting pathway, we generated stably transfected Caco-2 cell lines expressing various mutant bovine IGF-II/MPRs. The steady-state surface distribution of mutant receptors was analyzed by subjecting filter-grown cell monolayers to incubation with iodinated IGF-II/MPR-specific antibody or to indirect immunofluorescence and visualization by confocal microscopy. Together, these results demonstrate that the sorting of the IGF-II/MPR to the basolateral cell surface depends on recognition of sequences located in its cytoplasmic region that are distinct from the Tyr-based internalization and dileucine-dependent endosomal trafficking motifs.

Author List

Wick DA, Seetharam B, Dahms NM

Author

Nancy M. Dahms PhD Professor in the Biochemistry department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Amino Acid Sequence
Animals
Caco-2 Cells
Cattle
Cell Polarity
Gene Expression
Humans
Intestinal Mucosa
Leucine
Mutagenesis
Protein Sorting Signals
Protein Structure, Tertiary
Receptor, IGF Type 2
Transfection