title: Cloning of rat betacellulin and characterization of its expression in the gastrointestinal tract.
abstract: Betacellulin (BTC) is relatively a more recently discovered member of the EGF family of growth factors. As a prelude to its expression and functional studies in rat models of gut damage/repair, we have cloned rat BTC and examined its expression in the gastrointestinal tract. Rat BTC was found to be nearly identical to mouse betacellulin. A single 3 kb mRNA species was detected by Northern blotting, and ribonuclease protection analysis showed that its expression was ubiquitous but low in abundance throughout the gut. BTC mRNA and protein were found expressed in the gastric surface and upper pit epithelium as well as in some cells of gastric glands. In the jejunum, BTC mRNA and protein were localised to the crypt epithelium and in villous goblet cells. In the colon, BTC mRNA and protein were found produced in crypt and surface epithelium as well as in goblet cells. Taken together, the wide spread expression in the gut epithelium and in mucous cells in particular suggests an important and unique role for BTC in the gastrointestinal tract.
authors.affiliation: Cooperative Research Centre for Tissue Growth and Repair, North Adelaide, Australia.
authors.forename: N C
authors.initials: NC
authors.lastname: Kallincos
authors.forename: C J
authors.initials: CJ
authors.lastname: Xian
authors.forename: A J
authors.initials: AJ
authors.lastname: Dunbar
authors.forename: R T
authors.initials: RT
authors.lastname: Couper
authors.forename: L C
authors.initials: LC
authors.lastname: Read
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D066259:Betacellulin; D002417:Cattle; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004064:Digestive System / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D015870:Gene Expression; D006133:Growth Substances / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins; D051379:Mice; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: C587851:BTC protein, human; D066259:Betacellulin; C587852:Btc protein, mouse; C587853:Btc protein, rat; D018076:DNA, Complementary; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger