ID   CO3_XENLA               Reviewed;         323 AA.
AC   P23667;
DT   01-NOV-1991, integrated into UniProtKB/Swiss-Prot.
DT   01-FEB-1996, sequence version 2.
DT   25-MAY-2022, entry version 92.
DE   RecName: Full=Complement C3;
DE   Flags: Fragment;
GN   Name=c3;
OS   Xenopus laevis (African clawed frog).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC   Batrachia; Anura; Pipoidea; Pipidae; Xenopodinae; Xenopus; Xenopus.
OX   NCBI_TaxID=8355;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RX   PubMed=2919181; DOI=10.1073/pnas.86.4.1323;
RA   Grossberger D., Marcuz A., du Pasquier L., Lambris J.D.;
RT   "Conservation of structural and functional domains in complement component
RT   C3 of Xenopus and mammals.";
RL   Proc. Natl. Acad. Sci. U.S.A. 86:1323-1327(1989).
RN   [2]
RP   SEQUENCE REVISION.
RA   Lambris J.D.;
RL   Submitted (MAY-1995) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: C3 plays a central role in the activation of the complement
CC       system. Its processing by C3 convertase is the central reaction in both
CC       classical and alternative complement pathways. After activation C3b can
CC       bind covalently, via its reactive thioester, to cell surface
CC       carbohydrates or immune aggregates.
CC   -!- SUBCELLULAR LOCATION: Secreted.
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DR   EMBL; M21790; AAA67538.1; -; mRNA.
DR   PIR; A32329; A32329.
DR   AlphaFoldDB; P23667; -.
DR   SMR; P23667; -.
DR   Proteomes; UP000186698; Genome assembly.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0006957; P:complement activation, alternative pathway; IEA:UniProtKB-KW.
DR   GO; GO:0006958; P:complement activation, classical pathway; IEA:UniProtKB-KW.
DR   GO; GO:0006954; P:inflammatory response; IEA:UniProtKB-KW.
DR   CDD; cd03583; NTR_complement_C3; 1.
DR   Gene3D; 2.40.50.120; -; 1.
DR   Gene3D; 2.60.40.690; -; 1.
DR   InterPro; IPR009048; A-macroglobulin_rcpt-bd.
DR   InterPro; IPR036595; A-macroglobulin_rcpt-bd_sf.
DR   InterPro; IPR035711; Complement_C3-like.
DR   InterPro; IPR001134; Netrin_domain.
DR   InterPro; IPR018933; Netrin_module_non-TIMP.
DR   InterPro; IPR035815; NTR_complement_C3.
DR   InterPro; IPR008993; TIMP-like_OB-fold.
DR   PANTHER; PTHR11412:SF81; PTHR11412:SF81; 1.
DR   Pfam; PF07677; A2M_recep; 1.
DR   Pfam; PF01759; NTR; 1.
DR   SMART; SM01361; A2M_recep; 1.
DR   SMART; SM00643; C345C; 1.
DR   SUPFAM; SSF49410; SSF49410; 1.
DR   SUPFAM; SSF50242; SSF50242; 1.
DR   PROSITE; PS50189; NTR; 1.
PE   2: Evidence at transcript level;
KW   Complement alternate pathway; Complement pathway; Disulfide bond; Immunity;
KW   Inflammatory response; Innate immunity; Reference proteome; Secreted.
FT   CHAIN           <1..323
FT                   /note="Complement C3"
FT                   /id="PRO_0000048517"
FT   DOMAIN          177..321
FT                   /note="NTR"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00295"
FT   DISULFID        177..250
FT                   /evidence="ECO:0000250"
FT   DISULFID        197..321
FT                   /evidence="ECO:0000250"
FT   NON_TER         1
SQ   SEQUENCE   323 AA;  37070 MW;  3C8011BD9A1F15AD CRC64;
     GRVVTVYHAL VIEKERKCLN FELSVNVKEV QLARPPEGAK ATVSIEACAR HLKNVDATMS
     IIDISMMTGF SPDTDSLDRL MKGVDKYISK YEVNKGANDK GTLILYLDKV SHIDEECVKF
     YAHQYFEVGF IQPASVTVYD YYTPDNRCTK FYHVEEGSAL LGRICQGDIC RCAEENCFMQ
     QQIEGKITAD MRVNMACAPG VDFVYKATLT ELQPSDNYDN YVMTIKKVIK QGTDEDPEDK
     TRNFISHIKC RKALNMQLNR DYLIWGVTGD LWRQPDGYSY IIGKDTWMEW WPNERECQQR
     ENQDLCDDFE TVSDNLEIVG CPN