title: The glycan-binding properties of the cation-independent mannose 6-phosphate receptor are evolutionary conserved in vertebrates.
abstract: The 300-kDa cation-independent mannose 6-phosphate receptor (CI-MPR) plays an essential role in the biogenesis of lysosomes by delivering newly synthesized lysosomal enzymes from the trans Golgi network to the endosomal system. The CI-MPR is expressed in most eukaryotes, with Saccharomyces cerevisiae and Caenorhabditis elegans being notable exceptions. Although the repertoire of glycans recognized by the bovine receptor has been studied extensively, little is known concerning the ligand-binding properties of the CI-MPR from non-mammalian species. To assess the evolutionary conservation of the CI-MPR, surface plasmon resonance analyses using lysosomal enzymes with defined N-glycans were carried out to probe the glycan-binding specificity of the Danio rerio CI-MPR. The results demonstrate that the D. rerio CI-MPR harbors three glycan-binding sites that, like the bovine CI-MPR, map to domains 3, 5 and 9 of its 15-domain-containing extracytoplasmic region. Analyses on a phosphorylated glycan microarray further demonstrated the unique binding properties of each of the three sites and showed that, similar to the bovine CI-MPR, only domain 5 of the D. rerio CI-MPR is capable of recognizing Man-P-GlcNAc-containing glycans.
authors.affiliation: Department of Biochemistry,  Medical College of Wisconsin, Milwaukee, WI,  USA.
authors.forename: Alicia C
authors.initials: AC
authors.lastname: Castonguay
authors.forename: Yi
authors.initials: Y
authors.lastname: Lasanajak
authors.forename: Xuezheng
authors.initials: X
authors.lastname: Song
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Olson
authors.forename: Richard D
authors.initials: RD
authors.lastname: Cummings
authors.forename: David F
authors.initials: DF
authors.lastname: Smith
authors.forename: Nancy M
authors.initials: NM
authors.lastname: Dahms
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002478:Cells, Cultured; D044602:Cellulases / Q000737:chemistry; D017124:Conserved Sequence; D019143:Evolution, Molecular; D006801:Humans; D055767:Immobilized Proteins / Q000737:chemistry; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000737:chemistry*; D040081:Protein Array Analysis; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017527:Receptor, IGF Type 2 / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D013403:Sugar Phosphates / Q000737:chemistry; D020349:Surface Plasmon Resonance; D014714:Vertebrates; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D000520:alpha-Glucosidases / Q000737:chemistry
chemical_list: D055767:Immobilized Proteins; D011134:Polysaccharides; D017527:Receptor, IGF Type 2; D013403:Sugar Phosphates; D029961:Zebrafish Proteins; D044602:Cellulases; C509951:GAA protein, human; D000520:alpha-Glucosidases