Cloning and analysis of cDNA encoding a major airway glycoprotein, human tracheobronchial mucin (MUC5).

摘要: Two unique nucleotide probes for human tracheobronchial mucin glycoprotein (TBM) were generated via polymerase chain reaction with degenerate primers deduced from the TBM:TR-3A tryptic peptide sequence and used to isolate a 3.6 kilobase cDNA, clone NP3a, nasal polyp cDNA library. Clone NP3a was localized chromosome 11 contained 3168 open reading frame which encoded three TBM fragments, thus confirming that partially encodes TBM. also contains five tandem repeats of TTVGP/S an octapeptide GQCGTCTN, is conserved in intestinal MUC2 rat mucin-like protein (MLP) suggesting this has functional significance secreted mucins. amino acid similarity cysteine-rich domains at carboxyl termini MUC2, MLP, bovine porcine submaxillary mucins, von Willebrand factor. Strikingly, large percentage cysteine residues overlaps are highly conserved: 90% factor, 80% mucin, 70% 64% cysteines may be important tertiary structure glycoproteins. These studies demonstrate candidate MUC5, making it only gene reported date whose product been isolated airway secretions.