The protein encoded by this gene is a lysosomalcysteine protease composed of a dimer of disulfide-linked heavy and light chains, both produced from a single protein precursor. It is a member of the peptidase C1 family. At least five transcript variants encoding the same protein have been found for this gene.
Cathepsin B was once suspected as a candidate protease participating in the conversion of β-amyloid precursor protein into the amyloid plaques found in Alzheimer's disease patients. However, this function is now known to be mediated by BACE1 protease. It is now thought that cathepsin B can degrade β-amyloid precursor protein into harmless fragments. Thus, it is conceivable cathepsin B may play a pivotal role in the natural defense against Alzheimer's disease. Overexpression of cathepsin B has been associated with esophageal adenocarcinoma and other tumors.
^Chan SJ, San Segundo B, McCormick MB, Steiner DF (October 1986). "Nucleotide and predicted amino acid sequences of cloned human and mouse preprocathepsin B cDNAs". Proc. Natl. Acad. Sci. U.S.A.83 (20): 7721–5. doi:10.1073/pnas.83.20.7721. PMC386793. PMID3463996.
^Cao L, Taggart RT, Berquin IM, Moin K, Fong D, Sloane BF (February 1994). "Human gastric adenocarcinoma cathepsin B: isolation and sequencing of full-length cDNAs and polymorphisms of the gene". Gene139 (2): 163–9. doi:10.1016/0378-1119(94)90750-1. PMID8112600.
^ abPavlova A, Björk I (September 2003). "Grafting of features of cystatins C or B into the N-terminal region or second binding loop of cystatin A (stefin A) substantially enhances inhibition of cysteine proteinases". Biochemistry42 (38): 11326–33. doi:10.1021/bi030119v. PMID14503883.
^Pol E, Björk I (September 2001). "Role of the single cysteine residue, Cys 3, of human and bovine cystatin B (stefin B) in the inhibition of cysteine proteinases". Protein Sci.10 (9): 1729–38. doi:10.1110/ps.11901. PMC2253190. PMID11514663.
^Mai J, Finley RL, Waisman DM, Sloane BF (April 2000). "Human procathepsin B interacts with the annexin II tetramer on the surface of tumor cells". J. Biol. Chem.275 (17): 12806–12. doi:10.1074/jbc.275.17.12806. PMID10777578.
^Estrada S, Nycander M, Hill NJ, Craven CJ, Waltho JP, Björk I (May 1998). "The role of Gly-4 of human cystatin A (stefin A) in the binding of target proteinases. Characterization by kinetic and equilibrium methods of the interactions of cystatin A Gly-4 mutants with papain, cathepsin B, and cathepsin L". Biochemistry37 (20): 7551–60. doi:10.1021/bi980026r. PMID9585570.