Cathepsins are papain family cysteine proteinases that represent a major component of the lysosomal proteolytic system. In general, cathepsins contain a signal sequence, followed by a propeptide and then a catalytically active mature region. The very long (251-amino acid residues) proregion of the cathepsin F precursor contains a C-terminal domain similar to the pro-segment of cathepsin L-like enzymes, a 50-residue flexible linker peptide, and an N-terminal domain predicted to adopt a cystatin-like fold. The cathepsin F proregion is unique within the papain family cysteine proteases in that it contains this additional N-terminal segment predicted to share structural similarities with cysteine protease inhibitors of the cystatin superfamily. This cystatin-like domain contains some of the elements known to be important for inhibitory activity. CTSF encodes a predicted protein of 484 amino acids that contains a 19-residue signal peptide. Cathepsin F contains five potential N-glycosylation sites, and it may be targeted to the endosomal/lysosomal compartment via the mannose 6-phosphate receptor pathway. The cathepsin F gene is ubiquitously expressed, and it maps to chromosome 11q13, close to the gene encoding cathepsin W.
^Wang B, Shi GP, Yao PM, Li Z, Chapman HA, Bromme D (Dec 1998). "Human cathepsin F. Molecular cloning, functional expression, tissue localization, and enzymatic characterization". J Biol Chem273 (48): 32000–8. doi:10.1074/jbc.273.48.32000. PMID9822672.
^Santamaria I, Velasco G, Pendas AM, Paz A, Lopez-Otin C (Jun 1999). "Molecular cloning and structural and functional characterization of human cathepsin F, a new cysteine proteinase of the papain family with a long propeptide domain". J Biol Chem274 (20): 13800–9. doi:10.1074/jbc.274.20.13800. PMID10318784.
Nägler DK, Sulea T, Ménard R (1999). "Full-length cDNA of human cathepsin F predicts the presence of a cystatin domain at the N-terminus of the cysteine protease zymogen.". Biochem. Biophys. Res. Commun.257 (2): 313–8. doi:10.1006/bbrc.1999.0461. PMID10198209.
Wex T, Levy B, Wex H, Brömme D (1999). "Human cathepsins F and W: A new subgroup of cathepsins.". Biochem. Biophys. Res. Commun.259 (2): 401–7. doi:10.1006/bbrc.1999.0700. PMID10362521.
Wex T, Wex H, Brömme D (2000). "The human cathepsin F gene--a fusion product between an ancestral cathepsin and cystatin gene.". Biol. Chem.380 (12): 1439–42. doi:10.1515/BC.1999.185. PMID10661872.
Oörni K, Sneck M, Brömme D et al. (2004). "Cysteine protease cathepsin F is expressed in human atherosclerotic lesions, is secreted by cultured macrophages, and modifies low density lipoprotein particles in vitro.". J. Biol. Chem.279 (33): 34776–84. doi:10.1074/jbc.M310814200. PMID15184381.
Kaakinen R, Lindstedt KA, Sneck M et al. (2007). "Angiotensin II increases expression and secretion of cathepsin F in cultured human monocyte-derived macrophages: an angiotensin II type 2 receptor-mediated effect.". Atherosclerosis192 (2): 323–7. doi:10.1016/j.atherosclerosis.2006.08.001. PMID16963053.