Abstract
Meprins are plasma membrane homo- or hetero-oligomeric metalloendopeptidases that contain glycosylated α and/or β subunits. This paper reports the cloning and sequencing of the mouse kidney β subunit. The primary translation product is composed of 704 amino acids which includes a transient signal sequence of 20 amino acids at the NH2 terminus. The protease domain (Asn-63 to Leu-260) contains the putative zinc-binding motif characteristic of metalloendopeptidases of the "astacin family." The COOH terminus contains an epidermal growth factor-like domain, a potential membrane-spanning domain, and an additional 26 amino acids. The β subunit has an overall 42% identity to the α subunit, however, a 56-amino acid segment near the COOH terminus of α is missing in β, and the putative transmembrane and cytoplasmic domains of the subunits share no significant sequence similarity. NH2-terminal analyses of detergent-solubilized mature forms revealed that, unlike α, the prosequence (Leu-21 to Lys-62) is not removed from the β subunit. Northern blot analysis revealed a 2.5-kilobase message for the β subunit in the kidney and intestine of C57BL/6 and C3H/He mice. The gene for the β subunit was localized to mouse chromosome 18. These studies indicate that α and β probably derived from a common ancestral gene, but have evolved so that their genes are on two different chromosomes, and their tissue-specific expression and post-translational processing differ.
Original language | English (US) |
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Pages (from-to) | 21035-21043 |
Number of pages | 9 |
Journal | Journal of Biological Chemistry |
Volume | 268 |
Issue number | 28 |
State | Published - Oct 5 1993 |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology