tailieunhanh - Báo cáo Y học: Isolation and characterization of MUC15, a novel cell membrane-associated mucin

The present work reports isolation and characterization of a highly glycosylated protein from bovine milk fat globule membranes, known as PAS III. Partial amino-acid sequencing of the purified protein allowed construction of degenerate oligonucleotide primers, enabling isolation of a full-length cDNA encoding a protein of 330 amino-acid residues. N-terminal amino-acid sequencing of derived peptides and the purified protein confirmed 76% of the sequence and demonstrated presence of a cleavable signal peptide of 23 residues, leaving a mature protein of 307 amino acids. Database searches showed no homology to any other proteins. . | Eur. J. Biochem. 269 2755-2763 2002 FEBS 2002 doi Isolation and characterization of MUC15 a novel cell membrane-associated mucin Lone T. Pallesen Lars Berglund Lone K. Rasmussen Torben E. Petersen and Jan T. Rasmussen Protein Chemistry Laboratory Department of Molecular and Structural Biology University of Aarhus Denmark The present work reports isolation and characterization of a highly glycosylated protein from bovine milk fat globule membranes known as PAS III. Partial amino-acid sequencing of the purified protein allowed construction of degenerate oligonucleotide primers enabling isolation of a full-length cDNA encoding a protein of 330 amino-acid residues. N-terminal amino-acid sequencing of derived peptides and the purified protein confirmed 76 of the sequence and demonstrated presence of a cleavable signal peptide of 23 residues leaving a mature protein of 307 amino acids. Database searches showed no homology to any other proteins. A survey of the human genome indicated the presence of a corresponding gene on chromosome band . Isolation and sequencing of the complete cDNA sequence of the human homologue proved the existence of the gene product 334 amino-acid residues . This novel mucin-like protein was named MUC15 by appointment of the HUGO Gene Nomenclature Committee. The deduced amino-acid sequences of human and bovine MUC15 demonstrated structural hallmarks characteristic for other membrane-bound mucins such as a serine threonine and proline-rich extracellular region with several potential glycosylation sites a putative transmembrane domain and a short cytoplasmic C-terminal. We have shown the presence of O-glycosylations identified N-glycosylations at 11 of 15 potential sites in bovine MUC15 and a splice variant encoding a short secreted mucin. Finally analysis of human and bovine cDNA panels and libraries showed MUC15 gene expression in adult human spleen thymus prostate testis ovary small intestine colon .