Cathepsin L1

CTSL
Available structures PDB Human UniProt search: PDBe RCSB List of PDB id codes 1CJL, 1CS8, 1ICF, 1MHW, 2NQD, 2VHS, 2XU1, 2XU3, 2XU4, 2XU5, 2YJ2, 2YJ8, 2YJ9, 2YJB, 2YJC, 3BC3, 3H89, 3H8B, 3H8C, 3HHA, 3HWN, 3IV2, 3K24, 3KSE, 3OF8, 3OF9, 4AXL, 4AXM, 5F02, 5I4H
Identifiers
Aliases	CTSL, CATL, CTSL1, MEP, cathepsin L
External IDs	OMIM: 116880; HomoloGene: 129366; GeneCards: CTSL; OMA:CTSL - orthologs
Gene location (Human) Chr. Chromosome 9 (human) Band 9q21.33 Start 87,724,051 bp End 87,731,469 bp
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in stromal cell of endometrium decidua islet of Langerhans pericardium gallbladder upper lobe of left lung left uterine tube renal medulla muscle layer of sigmoid colon gastric mucosa n/a More reference expression data BioGPS More reference expression data
Gene ontology Molecular function fibronectin binding cysteine-type peptidase activity collagen binding histone binding serpin family protein binding peptidase activity protein binding cysteine-type endopeptidase activity hydrolase activity proteoglycan binding serine-type endopeptidase activity Cellular component extracellular region endolysosome lumen lysosomal lumen lysosome extracellular exosome nucleus extracellular space collagen-containing extracellular matrix multivesicular body plasma membrane Biological process macrophage apoptotic process antigen processing and presentation adaptive immune response antigen processing and presentation of exogenous peptide antigen via MHC class II extracellular matrix disassembly proteolysis toll-like receptor signaling pathway cellular response to thyroid hormone stimulus collagen catabolic process proteolysis involved in cellular protein catabolic process regulation of keratinocyte differentiation Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 1514 n/a Ensembl ENSG00000135047 n/a UniProt P07711 Q9HBQ7 n/a RefSeq (mRNA) NM_001257971 NM_001257972 NM_001257973 NM_001912 NM_145918 NM_001382757 NM_001382758 NM_001382766 NM_001382767 NM_001382768 n/a RefSeq (protein) NP_001244900 NP_001244901 NP_001244902 NP_001903 NP_666023 NP_001369686 NP_001369687 NP_001369695 NP_001369696 NP_001369697 NP_001244902.1 n/a Location (UCSC) Chr 9: 87.72 – 87.73 Mb n/a PubMed search n/a
Wikidata
View/Edit Human

Cathepsin L1 is a protein that in humans is encoded by the CTSL1 gene. The protein is a cysteine cathepsin, a lysosomal cysteine protease that plays a major role in intracellular protein catabolism.

Function

Cathepsin L1 is a member of the Peptidase C1 (cathepsin) MEROPS family, which plays an important role in diverse processes including normal lysosome mediated protein turnover, antigen and proprotein processing, and apoptosis. Its substrates include collagen and elastin, as well as alpha-1 protease inhibitor, a major controlling element of neutrophil elastase activity. The encoded protein has been implicated in several pathologic processes, including myofibril necrosis in myopathies and in myocardial ischemia, and in the renal tubular response to proteinuria. This protein, which is a member of the peptidase C1 family, is a dimer composed of disulfide-linked heavy and light chains, both produced from a single protein precursor. At least two transcript variants encoding the same protein have been found for this gene.

Viral entry

Cleavage of the SARS-CoV-2 S2 spike protein required for viral entry into cells can be accomplished by proteases TMPRSS2 located on the cell membrane, or by cathepsins (primarily cathepsin L) in endolysosomes. Hydroxychloroquine inhibits the action of cathepsin L in endolysosomes, but because cathepsin L cleavage is minor compared to TMPRSS2 cleavage, hydroxychloroquine does little to inhibit SARS-CoV-2 infection.

Inflammation

Although Cathepsin L is usually characterized as a lysosomal protease, it can be secreted, resulting in pathological inflammation. Cathepsin L and other cysteine cathepsins tend to be secreted by macrophages and other tissue-invading immune cells when causing pathological inflammation.

Interactions

CTSL1 has been shown to interact with Cystatin A.

Distribution

Cathepsin L has been reported in many organisms including fish, birds, mammals, and sponges.

See also

• Cathepsin L2 (also known as cathepsin V)

Further reading

• Smith CG, Smith MT, Besch NF, et al. (1980). "Effect of delta 9-tetrahydrocannabinol (THC) on female reproductive function". Advances in the Biosciences. 22–23: 449–67. doi:10.1016/b978-0-08-023759-6.50040-8. ISBN 9780080237596. PMID 116880.
• Goretzki L, Schmitt M, Mann K, et al. (1992). "Effective activation of the proenzyme form of the urokinase-type plasminogen activator (pro-uPA) by the cysteine protease cathepsin L." FEBS Lett. 297 (1–2): 112–8. Bibcode:1992FEBSL.297..112G. doi:10.1016/0014-5793(92)80339-I. PMID 1551416. S2CID 45421148.
• Dunn AD, Crutchfield HE, Dunn JT (1991). "Thyroglobulin processing by thyroidal proteases. Major sites of cleavage by cathepsins B, D, and L." J. Biol. Chem. 266 (30): 20198–204. doi:10.1016/S0021-9258(18)54909-7. PMID 1939080.
• Stearns NA, Dong JM, Pan JX, et al. (1991). "Comparison of cathepsin L synthesized by normal and transformed cells at the gene, message, protein, and oligosaccharide levels". Arch. Biochem. Biophys. 283 (2): 447–57. doi:10.1016/0003-9861(90)90666-M. PMID 2275556.
• Ritonja A, Popović T, Kotnik M, et al. (1988). "Amino acid sequences of the human kidney cathepsins H and L." FEBS Lett. 228 (2): 341–5. Bibcode:1988FEBSL.228..341R. doi:10.1016/0014-5793(88)80028-0. PMID 3342889. S2CID 45768546.
• Gal S, Gottesman MM (1988). "Isolation and sequence of a cDNA for human pro-(cathepsin L)". Biochem. J. 253 (1): 303–6. doi:10.1042/bj2530303. PMC 1149292. PMID 3421948.
• Johnson DA, Barrett AJ, Mason RW (1986). "Cathepsin L inactivates alpha 1-proteinase inhibitor by cleavage in the reactive site region". J. Biol. Chem. 261 (31): 14748–51. doi:10.1016/S0021-9258(18)66935-2. PMID 3490478.
• Mason RW, Walker JE, Northrop FD (1987). "The N-terminal amino acid sequences of the heavy and light chains of human cathepsin L. Relationship to a cDNA clone for a major cysteine proteinase from a mouse macrophage cell line". Biochem. J. 240 (2): 373–7. doi:10.1042/bj2400373. PMC 1147428. PMID 3545185.
• Joseph L, Lapid S, Sukhatme V (1987). "The major ras induced protein in NIH3T3 cells is cathepsin L." Nucleic Acids Res. 15 (7): 3186. doi:10.1093/nar/15.7.3186. PMC 340927. PMID 3550705.
• Kärgel HJ, Dettmer R, Etzold G, et al. (1982). "Action of rat liver cathepsin L on glucagon". Acta Biol. Med. Ger. 40 (9): 1139–43. PMID 7340337.
• Bevec T, Stoka V, Pungercic G, et al. (1996). "Major histocompatibility complex class II-associated p41 invariant chain fragment is a strong inhibitor of lysosomal cathepsin L." J. Exp. Med. 183 (4): 1331–8. doi:10.1084/jem.183.4.1331. PMC 2192513. PMID 8666891.
• Coulombe R, Grochulski P, Sivaraman J, et al. (1996). "Structure of human procathepsin L reveals the molecular basis of inhibition by the prosegment". EMBO J. 15 (20): 5492–503. doi:10.1002/j.1460-2075.1996.tb00934.x. PMC 452294. PMID 8896443.
• Baumgrass R, Williamson MK, Price PA (1997). "Identification of peptide fragments generated by digestion of bovine and human osteocalcin with the lysosomal proteinases cathepsin B, D, L, H, and S." J. Bone Miner. Res. 12 (3): 447–55. doi:10.1359/jbmr.1997.12.3.447. PMID 9076588. S2CID 20815411.
• Fujishima A, Imai Y, Nomura T, et al. (1997). "The crystal structure of human cathepsin L complexed with E-64". FEBS Lett. 407 (1): 47–50. Bibcode:1997FEBSL.407...47F. doi:10.1016/S0014-5793(97)00216-0. PMID 9141479. S2CID 46288832.
• Ménard R, Carmona E, Takebe S, et al. (1998). "Autocatalytic processing of recombinant human procathepsin L. Contribution of both intermolecular and unimolecular events in the processing of procathepsin L in vitro". J. Biol. Chem. 273 (8): 4478–84. doi:10.1074/jbc.273.8.4478. PMID 9468501.
• Schick C, Pemberton PA, Shi GP, et al. (1998). "Cross-class inhibition of the cysteine proteinases cathepsins K, L, and S by the serpin squamous cell carcinoma antigen 1: a kinetic analysis". Biochemistry. 37 (15): 5258–66. doi:10.1021/bi972521d. PMID 9548757.
• Estrada S, Nycander M, Hill NJ, et al. (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.". Biochemistry. 37 (20): 7551–60. doi:10.1021/bi980026r. PMID 9585570.
• Halfon S, Ford J, Foster J, et al. (1998). "Leukocystatin, a new Class II cystatin expressed selectively by hematopoietic cells". J. Biol. Chem. 273 (26): 16400–8. doi:10.1074/jbc.273.26.16400. PMID 9632704.

External links

• The MEROPS online database for peptidases and their inhibitors: C01.032
• Cathepsin+L at the U.S. National Library of Medicine Medical Subject Headings (MeSH)