Characterization of mouse cathepsin R, a new member of a family of placentally expressed cysteine proteases

A new mouse cysteine protease, termed cathepsin R. has been identified. The complete nucleotide sequence of this gene was derived from a set of cDNAs generated from 15.5-day mouse placenta. Sequence analysis revealed an open reading frame encoding a 334 amino acid long polypeptide closely related to placentally expressed cathepsins P, Q, and M. RT-PCR analysis indicated th at cathepsin R is only expressed in placenta and thus is a new member of th e emerging family of cathepsins whose expression is regulated during mouse embryonic development. Modeling and structural analysis suggests that cathe psin R will have a restricted substrate specificity when compared to that o f cathepsin L. (C) 2000 Elsevier Science B.V. All rights reserved.