Cathepsin L2

Cathepsin V (Adachi W. et al., 1998)
CTSL2 (gene locus)

Gene: CTSL2 maps to 9q21-22. The gene spans approximately 6.4 kb and consists of eight exons and seven introns. Genomic organization was similar to human cathepsin L and more than 50% similarity was found between the first introns of cathepsin L and L2, suggesting that they diverged late in evolution. The transcription initiation site, determined by primer extension, was 198 nucleotides from the first ATG. The 5' flanking region lacks a TATA box but has one SP1 site (Itoh R. et al., 1999).
mRNA: size: 1.8 kb.
Protein: a 334-amino acids (aa), 37-kD cysteine proteinase showing a wide identity (78%) with cathepsin L. Cathepsin L2 contains a 17-aa signal sequence and a 96-aa proregion. Recombinant protein displays cysteine proteinase activity in vitro, with substrate specificity similar to that of cathepsin L. The cysteine proteinases are a family of enzymes involved in many normal cellular processes and a number of pathologic conditions. They are synthesized as preproenzymes, which are processed to the corresponding proenzymes. The proenzymes are either targeted to the lysosome or continue along the cellular secretory route.

- Widespread cathepsin L2 expression was found in breast cancer and breast cancer cell lines, but not in normal mammary gland or in peritumoral tissue.

Adachi W. et al. (1998) Isolation and characterization of human cathepsin V: a major proteinase in corneal epithelium. Invest. Ophthal. Vis. Sci. 39, 1789-1796.
Itoh R. et al. (1999) Genomic organization and chromosomal localization of the human cathepsin L2 gene. DNA Res. 6, 137-140.
Santamaría I. et al. (1998) Cathepsin L2, a novel human cysteine proteinase produced by breast and colorectal carcinomas. Cancer Res. 58, 1624-1630.

Cathepsin B, cathepsin D, cathepsin K, cathepsin O