University at Buffalo - The State University of New York
Skip to Content
Structural features of the human salivary mucin, MUC7. - PubMed - NCBI
Format

Send to

Choose Destination
See comment in PubMed Commons below
Glycoconj J. 1998 May;15(5):457-67.

Structural features of the human salivary mucin, MUC7.

Author information

1
Department of Oral Biology and Research Center in Oral Biology, School of Dental Medicine, State University of New York at Buffalo, 14214, USA.

Abstract

Human salivary mucin (MUC7) is characterized by a single polypeptide chain of 357 aa. Detailed analysis of the derived MUC7 peptide sequence reveals five distinct regions or domains: (1) an N-terminal basic, histatin-like domain which has a leucine-zipper segment, (2) a moderately glycosylated domain, (3) six heavily glycosylated tandem repeats each consisting of 23 aa, (4) another heavily glycosylated MUC1- and MUC2-like domain, and (5) a C-terminal leucine-zipper segment. Chemical analysis and semi-empirical prediction algorithms for O-glycosylation suggested that 86/105 (83%) Ser/Thr residues were O-glycosylated with the majority located in the tandem repeats. The high (approximately 25%) proline content of MUC7 including 19 diproline segments suggested the presence of polyproline type structures. CD studies of natural and synthetic diproline-rich peptides and glycopeptides indicated that polyproline type structures do play a significant role in the conformational dynamics of MUC7. In addition, crystal structure analysis of a synthetic diproline segment (Boc-Ala-Pro-OBzl) revealed a polyproline type II extended structure. Collectively, the data indicate that the polyproline type II structure, dispersed throughout the tandem repeats, may impart a stiffening of the backbone and could act in consort with the glycosylated segments to keep MUC7 in a semi-rigid, rod shaped conformation resembling a 'bottle-brush' model.

PMID:
9881747
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Loading ...
    Support Center