CYSTATIN M, A NOVEL CYSTEINE PROTEINASE INHIBITOR

摘要

Isolated nucleic acid molecules encoding a novel cysteine proteinase inhibitor, cystatin M, which is a member of the Family 2 cystatins, are disclosed. Cystatin M exhibits cysteine proteinase inhibitory activity against papain, is downregulated in metastatic mammary epithelial tumor cells, as well as other tumor cells, and is upregulated in senescent cells. In addition to isolated nucleic acid molecules, the invention provides antisense nucleic acid molecules, recombinant expression vectors containing a nucelic acid molecule of the invention, host cells into which the expression vectors have been introduced and non-human transgenic animals in which a cystatin M gene has been introduced or disrupted. The invention further provides isolated cystatin M proteins, fusion proteins, antigenic peptides and anti-cystatin M antibodies. Diagnostic, screening and therapeutic methods utilizing compositions of the invention are also provided.