title: Cloning and complete coding sequence of a novel human cathepsin expressed in giant cells of osteoclastomas.
abstract: A gene encoding a possible novel human cathepsin, a cysteine proteinase that is distinct from previously characterized enzymes, has been identified by differential screening of a human osteoclastoma cDNA library. This molecule, termed cathepsin X, appears to represent the human homolog of the osteoclast-expressed rabbit cathepsin OC-2. Cathepsin X (GenBank accession number U20280) is 93.9% identical to OC-2 at the amino acid level, and is 92% identical at the nucleotide level within the coding region. Cathepsin X is 52.2 and 46.9% identical to cathepsins S and L, respectively, and is therefore clearly distinct from these enzymes. Cathepsin X mRNA was localized to multinucleated giant cells within the osteoclastoma tumor by in situ hybridization. These data strongly support the hypothesis that cathepsin X represents a novel cysteine proteinase which is expressed at high levels in osteoclasts.
authors.affiliation: Department of Cytokine Biology, Forsyth Dental Center, Boston, Massachusetts, USA.
authors.forename: Y P
authors.initials: YP
authors.lastname: Li
authors.forename: M
authors.initials: M
authors.lastname: Alexander
authors.forename: A L
authors.initials: AL
authors.lastname: Wucherpfennig
authors.forename: P
authors.initials: P
authors.lastname: Yelick
authors.forename: W
authors.initials: W
authors.lastname: Chen
authors.forename: P
authors.initials: P
authors.lastname: Stashenko
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D001859:Bone Neoplasms / Q000201:enzymology; D056657:Cathepsin K; D056668:Cathepsin L; D002403:Cathepsins / Q000737:chemistry* / Q000235:genetics; D003001:Cloning, Molecular; D003546:Cysteine Endopeptidases; D018076:DNA, Complementary / Q000737:chemistry* / Q000235:genetics; D010450:Endopeptidases; D006801:Humans; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010010:Osteoclasts / Q000201:enzymology*; D011817:Rabbits; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014407:Tumor Cells, Cultured
chemical_list: D018076:DNA, Complementary; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; C534281:CTSL protein, human; D056668:Cathepsin L; C028217:cathepsin S; C534130:CTSK protein, human; D056657:Cathepsin K