ID   IC1_RABIT               Reviewed;          18 AA.
AC   Q9TRG2;
DT   02-SEP-2008, integrated into UniProtKB/Swiss-Prot.
DT   01-MAY-2000, sequence version 1.
DT   25-MAY-2022, entry version 45.
DE   RecName: Full=Plasma protease C1 inhibitor {ECO:0000303|PubMed:8495195};
DE            Short=C1 Inh {ECO:0000250|UniProtKB:P05155};
DE            Short=C1Inh {ECO:0000250|UniProtKB:P05155};
DE   AltName: Full=C1 esterase inhibitor {ECO:0000250|UniProtKB:P05155};
DE   AltName: Full=C1-inhibiting factor {ECO:0000250|UniProtKB:P05155};
DE   AltName: Full=Serpin G1;
DE   Flags: Fragment;
GN   Name=SERPING1;
OS   Oryctolagus cuniculus (Rabbit).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Glires; Lagomorpha; Leporidae; Oryctolagus.
OX   NCBI_TaxID=9986;
RN   [1] {ECO:0000305}
RP   PROTEIN SEQUENCE, AND FUNCTION.
RC   TISSUE=Plasma {ECO:0000269|PubMed:8495195};
RX   PubMed=8495195; DOI=10.1002/pro.5560020504;
RA   Aulak K.S., Davis A.E. III, Donaldson V.H., Harrison R.A.;
RT   "Chymotrypsin inhibitory activity of normal C1-inhibitor and a P1 Arg to
RT   His mutant: evidence for the presence of overlapping reactive centers.";
RL   Protein Sci. 2:727-732(1993).
CC   -!- FUNCTION: Activation of the C1 complex is under control of the C1-
CC       inhibitor. It forms a proteolytically inactive stoichiometric complex
CC       with the C1r or C1s proteases. May play a potentially crucial role in
CC       regulating important physiological pathways including complement
CC       activation, blood coagulation, fibrinolysis and the generation of
CC       kinins. Very efficient inhibitor of FXIIa. Inhibits chymotrypsin and
CC       kallikrein. {ECO:0000250|UniProtKB:P05155, ECO:0000269|PubMed:8495195}.
CC   -!- SUBUNIT: Interacts with MASP1. {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:P05155}.
CC   -!- PTM: Glycosylated. {ECO:0000250|UniProtKB:P05155}.
CC   -!- SIMILARITY: Belongs to the serpin family. {ECO:0000255}.
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DR   AlphaFoldDB; Q9TRG2; -.
DR   eggNOG; KOG2392; Eukaryota.
DR   Proteomes; UP000001811; Unplaced.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0004867; F:serine-type endopeptidase inhibitor activity; ISS:UniProtKB.
DR   GO; GO:0007596; P:blood coagulation; IEA:UniProtKB-KW.
DR   GO; GO:0006958; P:complement activation, classical pathway; IEA:UniProtKB-KW.
DR   GO; GO:0042730; P:fibrinolysis; IEA:UniProtKB-KW.
DR   GO; GO:0045087; P:innate immune response; IEA:UniProtKB-KW.
DR   GO; GO:0001869; P:negative regulation of complement activation, lectin pathway; ISS:UniProtKB.
DR   PROSITE; PS00284; SERPIN; 1.
PE   1: Evidence at protein level;
KW   Blood coagulation; Complement pathway; Direct protein sequencing;
KW   Fibrinolysis; Glycoprotein; Hemostasis; Immunity; Innate immunity;
KW   Protease inhibitor; Reference proteome; Secreted;
KW   Serine protease inhibitor.
FT   CHAIN           <1..>18
FT                   /note="Plasma protease C1 inhibitor"
FT                   /id="PRO_0000348610"
FT   SITE            2..3
FT                   /note="Reactive bond for chymotrypsin"
FT                   /evidence="ECO:0000250|UniProtKB:P05155"
FT   SITE            3..4
FT                   /note="Reactive bond"
FT                   /evidence="ECO:0000250|UniProtKB:P05155"
FT   NON_TER         1
FT                   /evidence="ECO:0000303|PubMed:8495195"
FT   NON_TER         18
FT                   /evidence="ECO:0000303|PubMed:8495195"
SQ   SEQUENCE   18 AA;  2134 MW;  6A74AE635AF54C5E CRC64;
     VARSLLIFEV QQPFLFLL