Characteristics of rodent intestinal mucin Muc3 and alterations in a mouse model of human cystic fibrosis

Human mucin MUC3 and rodent Muc3 are widely assumed to represent secretory mucins expressed in columnar and goblet cells of the intestine. Using a 3'-oligonucleotide probe and in situ hybridization, we observed expression of rat Muc3 mostly in columnar cells. Two antibodies specific for COOH-te...

Full description

Saved in:
Bibliographic Details
Published in:American journal of physiology: Gastrointestinal and liver physiology 2001-06, Vol.280 (6), p.G1321-G1330
Main Authors: Khatri, I A, Ho, C, Specian, R D, Forstner, J F
Format: Article
Language:English
Subjects:
Amino Acid Sequence - genetics
Animals
Cesium
Chlorides
Cystic Fibrosis - genetics
Cystic Fibrosis - metabolism
Cystic Fibrosis - pathology
Cytoplasm - metabolism
Disease Models, Animal
Epitopes - metabolism
Fluorescent Antibody Technique
Intestines - metabolism
Intestines - pathology
Male
Mice
Microvilli - metabolism
Molecular Sequence Data
Mucin-2
Mucin-3
Mucins - chemistry
Mucins - immunology
Mucins - metabolism
Rats
Rats, Wistar
Reference Values
Sucrase - metabolism
Tissue Distribution
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Human mucin MUC3 and rodent Muc3 are widely assumed to represent secretory mucins expressed in columnar and goblet cells of the intestine. Using a 3'-oligonucleotide probe and in situ hybridization, we observed expression of rat Muc3 mostly in columnar cells. Two antibodies specific for COOH-terminal epitopes of Muc3 localized to apical membranes and cytoplasm of columnar cells. An antibody to the tandem repeat (TR) sequence (TTTPDV)3, however, localized to both columnar and goblet cells. On CsCl gradients, Muc3 appeared in both light- and heavy-density fractions. The lighter species was immunoreactive with all three antibodies, whereas the heavier species reacted only with anti-TR antibody. Thus Muc3 is expressed in two forms, a full-length membrane-associated form found in columnar cells (light density) and a carboxyl-truncated soluble form present in goblet cells (heavy density). In a mouse model of human cystic fibrosis, both soluble Muc3 and goblet cell Muc2 were increased in amount and hypersecreted. Thus Muc2 and Muc3 contribute to the excess intestinal luminal mucus of cystic fibrosis mice.
ISSN:0193-1857
1522-1547
DOI:10.1152/ajpgi.2001.280.6.g1321