Faculty Collaboration Database

Identification of residues essential for carbohydrate recognition by the insulin-like growth factor II/mannose 6-phosphate receptor. J Biol Chem 2002 Mar 29;277(13):11255-64

Date

01/19/2002

Pubmed ID

11799115

DOI

10.1074/jbc.M109855200

Scopus ID

2-s2.0-0037192762 (requires institutional sign-in at Scopus site)   54 Citations

Abstract

Two distinct mannose 6-phosphate (Man-6-P) receptors (MPRs), the cation-dependent MPR (CD-MPR) and the insulin-like growth factor II/MPR (IGF-II/MPR), recognize a diverse population of Man-6-P-containing ligands. The IGF-II/MPR is a type I transmembrane glycoprotein with a large extracytoplasmic region composed of 15 repeating domains that display sequence identity to each other and to the single extracytoplasmic domain of the CD-MPR. A structure-based sequence alignment of the two distinct Man-6-P-binding sites of the IGF-II/MPR with the CD-MPR implicates several residues of IGF-II/MPR domains 3 and 9 as essential for Man-6-P binding. To test this hypothesis single amino acid substitutions were made in constructs encoding either the N- or the C-terminal Man-6-P-binding sites of the bovine IGF-II/MPR. The mutant IGF-II/MPRs secreted from COS-1 cells were analyzed by pentamannosyl phosphate-agarose affinity chromatography, identifying four residues (Gln-392, Ser-431, Glu-460, and Tyr-465) in domain 3 and four residues (Gln-1292, His-1329, Glu-1354, and Tyr-1360) in domain 9 as essential for Man-6-P recognition. Binding affinity studies using the lysosomal enzyme, beta-glucuronidase, confirmed these results. Together these analyses provide strong evidence that the two Man-6-P-binding sites of the IGF-II/MPR are structurally similar to each other and to the CD-MPR and utilize a similar carbohydrate recognition mechanism.

Author List

Hancock MK, Haskins DJ, Sun G, 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
Base Sequence
Binding Sites
DNA Primers
Insulin-Like Growth Factor II
Molecular Sequence Data
Mutagenesis, Site-Directed
Sequence Homology, Amino Acid