ID   CATK_CHICK              Reviewed;         334 AA.
AC   Q90686;
DT   15-NOV-2002, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1996, sequence version 1.
DT   03-AUG-2022, entry version 108.
DE   RecName: Full=Cathepsin K;
DE            EC=3.4.22.38;
DE   AltName: Full=JTAP-1;
DE   Flags: Precursor;
GN   Name=CTSK;
OS   Gallus gallus (Chicken).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Archelosauria; Archosauria; Dinosauria; Saurischia; Theropoda;
OC   Coelurosauria; Aves; Neognathae; Galloanserae; Galliformes; Phasianidae;
OC   Phasianinae; Gallus.
OX   NCBI_TaxID=9031 {ECO:0000312|EMBL:AAC59739.1};
RN   [1] {ECO:0000305}
RP   NUCLEOTIDE SEQUENCE [MRNA], AND INDUCTION.
RX   PubMed=8552384;
RA   Hadman M., Gabos L., Loo M., Sehgal A., Bos T.J.;
RT   "Isolation and cloning of JTAP-1: a cathepsin like gene upregulated in
RT   response to V-Jun induced cell transformation.";
RL   Oncogene 12:135-142(1996).
CC   -!- FUNCTION: Closely involved in osteoclastic bone resorption and may
CC       participate partially in the disorder of bone remodeling. Displays
CC       potent endoprotease activity against fibrinogen at acid pH. May play an
CC       important role in extracellular matrix degradation (By similarity).
CC       {ECO:0000250|UniProtKB:P43235}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=Broad proteolytic activity. With small-molecule substrates and
CC         inhibitors, the major determinant of specificity is P2, which is
CC         preferably Leu, Met > Phe, and not Arg.; EC=3.4.22.38;
CC         Evidence={ECO:0000250|UniProtKB:P43235};
CC   -!- INDUCTION: Up-regulated in response to V-Jun induced cell
CC       transformation. {ECO:0000269|PubMed:8552384}.
CC   -!- SIMILARITY: Belongs to the peptidase C1 family. {ECO:0000255|PROSITE-
CC       ProRule:PRU10088, ECO:0000255|PROSITE-ProRule:PRU10089,
CC       ECO:0000255|PROSITE-ProRule:PRU10090}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; U37691; AAC59739.1; -; mRNA.
DR   AlphaFoldDB; Q90686; -.
DR   SMR; Q90686; -.
DR   STRING; 9031.ENSGALP00000043433; -.
DR   MEROPS; C01.036; -.
DR   VEuPathDB; HostDB:geneid_395818; -.
DR   eggNOG; KOG1543; Eukaryota.
DR   InParanoid; Q90686; -.
DR   PhylomeDB; Q90686; -.
DR   Proteomes; UP000000539; Unplaced.
DR   GO; GO:0004197; F:cysteine-type endopeptidase activity; IEA:UniProtKB-EC.
DR   GO; GO:0006508; P:proteolysis; IEA:UniProtKB-KW.
DR   CDD; cd02248; Peptidase_C1A; 1.
DR   InterPro; IPR038765; Papain-like_cys_pep_sf.
DR   InterPro; IPR025661; Pept_asp_AS.
DR   InterPro; IPR000169; Pept_cys_AS.
DR   InterPro; IPR025660; Pept_his_AS.
DR   InterPro; IPR000668; Peptidase_C1A_C.
DR   InterPro; IPR015644; Peptidase_C1A_cathepsin-K.
DR   InterPro; IPR039417; Peptidase_C1A_papain-like.
DR   PANTHER; PTHR12411:SF55; PTHR12411:SF55; 1.
DR   Pfam; PF00112; Peptidase_C1; 1.
DR   PRINTS; PR00705; PAPAIN.
DR   SMART; SM00645; Pept_C1; 1.
DR   SUPFAM; SSF54001; SSF54001; 1.
DR   PROSITE; PS00640; THIOL_PROTEASE_ASN; 1.
DR   PROSITE; PS00139; THIOL_PROTEASE_CYS; 1.
DR   PROSITE; PS00639; THIOL_PROTEASE_HIS; 1.
PE   2: Evidence at transcript level;
KW   Disulfide bond; Glycoprotein; Hydrolase; Protease; Reference proteome;
KW   Signal; Thiol protease; Zymogen.
FT   SIGNAL          1..19
FT                   /evidence="ECO:0000255"
FT   PROPEP          20..119
FT                   /note="Activation peptide"
FT                   /id="PRO_0000026309"
FT   CHAIN           120..334
FT                   /note="Cathepsin K"
FT                   /id="PRO_0000026310"
FT   ACT_SITE        144
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        281
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        301
FT                   /evidence="ECO:0000250"
FT   CARBOHYD        108
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   DISULFID        141..182
FT                   /evidence="ECO:0000250"
FT   DISULFID        175..215
FT                   /evidence="ECO:0000250"
FT   DISULFID        274..323
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   334 AA;  37219 MW;  DB3E23FBC21BF3B9 CRC64;
     MLRLHWLALL VLLLPMAAAQ LRPEPELDAQ WDLWKRTIQK AVQRQGGRNV PEVDLGEEPE
     VHRCPQRGAR LGKHSFQLAM NYLGDMTSEE VVRTMTGLRV PRSRPRPNGT LYVPDWSSRA
     PAAVDWRRKG YVTPVKDQGQ CGSCWAFSSV GALEGQLKRR TGKLLSLSPQ NLVYCVSNNN
     GCGGGYMTNA FEYVRLNRGI DSEDAYPYIG QDESCMYSPT GKAAKCRGYR EIPEDNEKAL
     KRAVARIGPV SVGIDASLPS FQFYSRGVYY DTGCNPENIN HAVLAVGYGA QKGTKHWIIK
     NSWGTEWGNK GYVLLARNMK QTCGIANLAS FPKM