Developmental expression of meprin metalloprotease subunits in ICR and C3H/He mouse kidney and intestine in the embryo, postnatally and after weaning

Meprins are secreted and membrane-bound metalloendopeptidases highly expres sed in kidney and intestinal epithelial cells. They are oligomeric glycopro teins composed of evolutionarily related alpha and/or beta subunits. The pr esent work revealed that the messages for both meprin subunits were express ed in intestine and kidney in ICR and C3H/He mouse embryos (as early as day 11), indicating developmental functions for both subunits. During the firs t 2 weeks after birth, the mRNA levels for both subunits increased in ICR m ice, but between 10 days and 3 weeks (time of weaning) the ex subunit level in the intestine fell markedly. In adult ICR mice, meprin beta mRNA was co nsistently expressed in both kidney and intestine, whereas meprin a mRNA wa s highly expressed in kidney but only present at low levels in intestine. I n C3H/He mice, the pattern of meprin a and a subunit mRNA expression was si milar to that of ICR mice, except that meprin alpha was barely detectable i n kidney after birth. The results of postnatal studies indicate that the me prin alpha subunit has a role in the intestine during suckling but is not e ssential after weaning, and that the beta homooligomer is the major meprin form after weaning in both kidney and intestine. (C) 2001 Elsevier Science B.V. All rights reserved.