Molecular cloning of a major human gall bladder mucin: complete C-terminal sequence and genomic organization of MUC5B.

摘要: Gall bladder mucin has been shown to play a central role in the pathogenesis of cholesterol gallstone disease. While cloning and sequencing studies have provided wealth information on structure other gastrointestinal respiratory mucins, nothing is known about primary human gall mucin. In this study, we show that tracheobronchial MUC5B major gene product expressed bladder. Antibodies directed against deglycosylated were used screen cDNA expression library, most isolated clones contained repetitive sequences nearly identical with those tandem repeat region MUC5B. An additional clone (hGBM2-3) an open reading frame coding for 389 residue cysteine-rich sequence. The arrangement cysteine residues sequence was very similar C-terminal regions MUC2, MUC5AC von Willebrand factor. This connected series degenerate repeats 7.5 kb HincII genomic DNA fragment. fragment, ten exons nine introns, exon 1 469 2-10 152 nucleotide overlap hGBM2-3. Interestingly, exon-intron junctions fragment occurred at positions equivalent D4 domain factor, suggesting these proteins evolved from common evolutionary ancestor through addition or deletion encoding functional domains.