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Database: UniProt
Entry: CR2_HUMAN
LinkDB: CR2_HUMAN
Original site: CR2_HUMAN 
ID   CR2_HUMAN               Reviewed;        1033 AA.
AC   P20023; C9JHD2; Q13866; Q14212; Q53EL2; Q5BKT9; Q5SR46; Q5SR48;
DT   01-FEB-1991, integrated into UniProtKB/Swiss-Prot.
DT   25-NOV-2008, sequence version 2.
DT   27-MAR-2024, entry version 226.
DE   RecName: Full=Complement receptor type 2;
DE            Short=Cr2;
DE   AltName: Full=Complement C3d receptor;
DE   AltName: Full=Epstein-Barr virus receptor;
DE            Short=EBV receptor;
DE   AltName: CD_antigen=CD21;
DE   Flags: Precursor;
GN   Name=CR2; Synonyms=C3DR;
OS   Homo sapiens (Human).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae;
OC   Homo.
OX   NCBI_TaxID=9606;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], AND VARIANT GLU-1003.
RX   PubMed=2563370; DOI=10.1016/s0021-9258(18)94149-9;
RA   Fujisaku A., Harley J.B., Frank M.B., Gruner B.A., Frazier B., Holers V.M.;
RT   "Genomic organization and polymorphisms of the human C3d/Epstein-Barr virus
RT   receptor.";
RL   J. Biol. Chem. 264:2118-2125(1989).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [MRNA], AND VARIANT VAL-993.
RC   TISSUE=B-cell;
RX   PubMed=2832506; DOI=10.1084/jem.167.3.1047;
RA   Weis J.J., Toothaker L.E., Smith J.A., Weis J.H., Fearon D.T.;
RT   "Structure of the human B lymphocyte receptor for C3d and the Epstein-Barr
RT   virus and relatedness to other members of the family of C3/C4 binding
RT   proteins.";
RL   J. Exp. Med. 167:1047-1066(1988).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM C), AND VARIANT GLU-1003.
RX   PubMed=2827171; DOI=10.1073/pnas.84.24.9194;
RA   Moore M., Cooper N., Tack B., Nemerow G.;
RT   "Molecular cloning of the cDNA encoding the Epstein-Barr virus.C3d receptor
RT   (complement receptor type 2) of human b lymphocytes.";
RL   Proc. Natl. Acad. Sci. U.S.A. 84:9194-9198(1987).
RN   [4]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS A; C AND D).
RX   PubMed=10068037; DOI=10.1016/s0161-5890(98)00098-4;
RA   Barel M., Balbo M., Frade R.;
RT   "Evidence for a new transcript of the Epstein-Barr virus/C3d receptor (CR2,
RT   CD21) which is due to alternative exon usage.";
RL   Mol. Immunol. 35:1025-1031(1998).
RN   [5]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM C).
RC   TISSUE=Synovium;
RX   PubMed=14702039; DOI=10.1038/ng1285;
RA   Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R.,
RA   Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H.,
RA   Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.,
RA   Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K.,
RA   Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H.,
RA   Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M.,
RA   Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K.,
RA   Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T.,
RA   Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M.,
RA   Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S.,
RA   Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H.,
RA   Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K.,
RA   Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N.,
RA   Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S.,
RA   Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O.,
RA   Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H.,
RA   Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B.,
RA   Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y.,
RA   Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K.,
RA   Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T.,
RA   Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T.,
RA   Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y.,
RA   Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H.,
RA   Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y.,
RA   Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H.,
RA   Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O.,
RA   Isogai T., Sugano S.;
RT   "Complete sequencing and characterization of 21,243 full-length human
RT   cDNAs.";
RL   Nat. Genet. 36:40-45(2004).
RN   [6]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM C).
RC   TISSUE=Spleen;
RA   Totoki Y., Toyoda A., Takeda T., Sakaki Y., Tanaka A., Yokoyama S.;
RL   Submitted (APR-2005) to the EMBL/GenBank/DDBJ databases.
RN   [7]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA   Livingston R.J., Shaffer T., McFarland I., Nguyen C.P., Stanaway I.B.,
RA   Rajkumar N., Johnson E.J., da Ponte S.H., Willa H., Ahearn M.O.,
RA   Bertucci C., Acklestad J., Carroll A., Swanson J., Gildersleeve H.I.,
RA   Nickerson D.A.;
RL   Submitted (OCT-2006) to the EMBL/GenBank/DDBJ databases.
RN   [8]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RX   PubMed=16710414; DOI=10.1038/nature04727;
RA   Gregory S.G., Barlow K.F., McLay K.E., Kaul R., Swarbreck D., Dunham A.,
RA   Scott C.E., Howe K.L., Woodfine K., Spencer C.C.A., Jones M.C., Gillson C.,
RA   Searle S., Zhou Y., Kokocinski F., McDonald L., Evans R., Phillips K.,
RA   Atkinson A., Cooper R., Jones C., Hall R.E., Andrews T.D., Lloyd C.,
RA   Ainscough R., Almeida J.P., Ambrose K.D., Anderson F., Andrew R.W.,
RA   Ashwell R.I.S., Aubin K., Babbage A.K., Bagguley C.L., Bailey J.,
RA   Beasley H., Bethel G., Bird C.P., Bray-Allen S., Brown J.Y., Brown A.J.,
RA   Buckley D., Burton J., Bye J., Carder C., Chapman J.C., Clark S.Y.,
RA   Clarke G., Clee C., Cobley V., Collier R.E., Corby N., Coville G.J.,
RA   Davies J., Deadman R., Dunn M., Earthrowl M., Ellington A.G., Errington H.,
RA   Frankish A., Frankland J., French L., Garner P., Garnett J., Gay L.,
RA   Ghori M.R.J., Gibson R., Gilby L.M., Gillett W., Glithero R.J.,
RA   Grafham D.V., Griffiths C., Griffiths-Jones S., Grocock R., Hammond S.,
RA   Harrison E.S.I., Hart E., Haugen E., Heath P.D., Holmes S., Holt K.,
RA   Howden P.J., Hunt A.R., Hunt S.E., Hunter G., Isherwood J., James R.,
RA   Johnson C., Johnson D., Joy A., Kay M., Kershaw J.K., Kibukawa M.,
RA   Kimberley A.M., King A., Knights A.J., Lad H., Laird G., Lawlor S.,
RA   Leongamornlert D.A., Lloyd D.M., Loveland J., Lovell J., Lush M.J.,
RA   Lyne R., Martin S., Mashreghi-Mohammadi M., Matthews L., Matthews N.S.W.,
RA   McLaren S., Milne S., Mistry S., Moore M.J.F., Nickerson T., O'Dell C.N.,
RA   Oliver K., Palmeiri A., Palmer S.A., Parker A., Patel D., Pearce A.V.,
RA   Peck A.I., Pelan S., Phelps K., Phillimore B.J., Plumb R., Rajan J.,
RA   Raymond C., Rouse G., Saenphimmachak C., Sehra H.K., Sheridan E.,
RA   Shownkeen R., Sims S., Skuce C.D., Smith M., Steward C., Subramanian S.,
RA   Sycamore N., Tracey A., Tromans A., Van Helmond Z., Wall M., Wallis J.M.,
RA   White S., Whitehead S.L., Wilkinson J.E., Willey D.L., Williams H.,
RA   Wilming L., Wray P.W., Wu Z., Coulson A., Vaudin M., Sulston J.E.,
RA   Durbin R.M., Hubbard T., Wooster R., Dunham I., Carter N.P., McVean G.,
RA   Ross M.T., Harrow J., Olson M.V., Beck S., Rogers J., Bentley D.R.;
RT   "The DNA sequence and biological annotation of human chromosome 1.";
RL   Nature 441:315-321(2006).
RN   [9]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS A AND C), AND VARIANT
RP   ASN-639.
RC   TISSUE=Lymph;
RX   PubMed=15489334; DOI=10.1101/gr.2596504;
RG   The MGC Project Team;
RT   "The status, quality, and expansion of the NIH full-length cDNA project:
RT   the Mammalian Gene Collection (MGC).";
RL   Genome Res. 14:2121-2127(2004).
RN   [10]
RP   PROTEIN SEQUENCE OF 226-233; 256-267; 332-341; 667-677 AND 898-908.
RX   PubMed=3016712; DOI=10.1073/pnas.83.15.5639;
RA   Weis J.J., Fearon D.T., Klickstein L.B., Wong W.W., Richards S.A.,
RA   de Bruyn Kops A., Smith J.A., Weis J.H.;
RT   "Identification of a partial cDNA clone for the C3d/Epstein-Barr virus
RT   receptor of human B lymphocytes: homology with the receptor for fragments
RT   C3b and C4b of the third and fourth components of complement.";
RL   Proc. Natl. Acad. Sci. U.S.A. 83:5639-5643(1986).
RN   [11]
RP   NUCLEOTIDE SEQUENCE [MRNA] OF 492-556 (ISOFORM B).
RX   PubMed=8390533;
RA   Sinha S.K., Todd S.C., Hedrick J.A., Speiser C.L., Lambris J.D.,
RA   Tsoukas C.D.;
RT   "Characterization of the EBV/C3d receptor on the human Jurkat T cell line:
RT   evidence for a novel transcript.";
RL   J. Immunol. 150:5311-5320(1993).
RN   [12]
RP   FUNCTION (MICROBIAL INFECTION), AND INTERACTION WITH EPSTEIN-BARR VIRUS
RP   GP350 PROTEIN.
RX   PubMed=2460635; DOI=10.1128/jvi.62.12.4452-4464.1988;
RA   Tanner J., Whang Y., Sample J., Sears A., Kieff E.;
RT   "Soluble gp350/220 and deletion mutant glycoproteins block Epstein-Barr
RT   virus adsorption to lymphocytes.";
RL   J. Virol. 62:4452-4464(1988).
RN   [13]
RP   INTERACTION WITH CD19, AND SUBCELLULAR LOCATION.
RX   PubMed=1702139; DOI=10.1084/jem.173.1.55;
RA   Matsumoto A.K., Kopicky-Burd J., Carter R.H., Tuveson D.A., Tedder T.F.,
RA   Fearon D.T.;
RT   "Intersection of the complement and immune systems: a signal transduction
RT   complex of the B lymphocyte-containing complement receptor type 2 and
RT   CD19.";
RL   J. Exp. Med. 173:55-64(1991).
RN   [14]
RP   IDENTIFICATION IN A COMPLEX WITH CD19; CD81 AND IFITM1, AND SUBCELLULAR
RP   LOCATION.
RX   PubMed=1383329;
RA   Bradbury L.E., Kansas G.S., Levy S., Evans R.L., Tedder T.F.;
RT   "The CD19/CD21 signal transducing complex of human B lymphocytes includes
RT   the target of antiproliferative antibody-1 and Leu-13 molecules.";
RL   J. Immunol. 149:2841-2850(1992).
RN   [15]
RP   FUNCTION AS A RECEPTOR FOR HNRNPU.
RX   PubMed=7753047; DOI=10.1016/0161-5890(95)00005-y;
RA   Barel M., Balbo M., Gauffre A., Frade R.;
RT   "Binding sites of the Epstein-Barr virus and C3d receptor (CR2, CD21) for
RT   its three intracellular ligands, the p53 anti-oncoprotein, the p68 calcium
RT   binding protein and the nuclear p120 ribonucleoprotein.";
RL   Mol. Immunol. 32:389-397(1995).
RN   [16]
RP   GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-623.
RC   TISSUE=Leukemic T-cell;
RX   PubMed=19349973; DOI=10.1038/nbt.1532;
RA   Wollscheid B., Bausch-Fluck D., Henderson C., O'Brien R., Bibel M.,
RA   Schiess R., Aebersold R., Watts J.D.;
RT   "Mass-spectrometric identification and relative quantification of N-linked
RT   cell surface glycoproteins.";
RL   Nat. Biotechnol. 27:378-386(2009).
RN   [17]
RP   INTERACTION WITH FCER2.
RX   PubMed=16172256; DOI=10.1084/jem.20050811;
RA   Hibbert R.G., Teriete P., Grundy G.J., Beavil R.L., Reljic R., Holers V.M.,
RA   Hannan J.P., Sutton B.J., Gould H.J., McDonnell J.M.;
RT   "The structure of human CD23 and its interactions with IgE and CD21.";
RL   J. Exp. Med. 202:751-760(2005).
RN   [18]
RP   INVOLVEMENT IN CVID7.
RX   PubMed=22035880; DOI=10.1016/j.jaci.2011.09.027;
RA   Thiel J., Kimmig L., Salzer U., Grudzien M., Lebrecht D., Hagena T.,
RA   Draeger R., Volxen N., Bergbreiter A., Jennings S., Gutenberger S.,
RA   Aichem A., Illges H., Hannan J.P., Kienzler A.K., Rizzi M., Eibel H.,
RA   Peter H.H., Warnatz K., Grimbacher B., Rump J.A., Schlesier M.;
RT   "Genetic CD21 deficiency is associated with hypogammaglobulinemia.";
RL   J. Allergy Clin. Immunol. 129:801-810(2012).
RN   [19]
RP   X-RAY CRYSTALLOGRAPHY (2.04 ANGSTROMS) OF 21-153 IN COMPLEX WITH C3, AND
RP   DISULFIDE BONDS.
RX   PubMed=11387479; DOI=10.1126/science.1059118;
RA   Szakonyi G., Guthridge J.M., Li D., Young K., Holers V.M., Chen X.S.;
RT   "Structure of complement receptor 2 in complex with its C3d ligand.";
RL   Science 292:1725-1728(2001).
RN   [20]
RP   X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF 22-148, DISULFIDE BONDS, AND
RP   GLYCOSYLATION AT ASN-121 AND ASN-127.
RX   PubMed=12122212; DOI=10.1073/pnas.162360499;
RA   Prota A.E., Sage D.R., Stehle T., Fingeroth J.D.;
RT   "The crystal structure of human CD21: Implications for Epstein-Barr virus
RT   and C3d binding.";
RL   Proc. Natl. Acad. Sci. U.S.A. 99:10641-10646(2002).
RN   [21]
RP   X-RAY SCATTERING SOLUTION STRUCTURE OF 21-971.
RX   PubMed=16950392; DOI=10.1016/j.jmb.2006.08.012;
RA   Gilbert H.E., Asokan R., Holers V.M., Perkins S.J.;
RT   "The 15 SCR flexible extracellular domains of human complement receptor
RT   type 2 can mediate multiple ligand and antigen interactions.";
RL   J. Mol. Biol. 362:1132-1147(2006).
RN   [22]
RP   X-RAY CRYSTALLOGRAPHY (3.16 ANGSTROMS) OF 996-1303 IN COMPLEX WITH C3,
RP   INTERACTION WITH C3, DISULFIDE BONDS, AND MUTAGENESIS OF ARG-103; ASP-112
RP   AND LYS-128.
RX   PubMed=21527715; DOI=10.1126/science.1201954;
RA   van den Elsen J.M., Isenman D.E.;
RT   "A crystal structure of the complex between human complement receptor 2 and
RT   its ligand C3d.";
RL   Science 332:608-611(2011).
RN   [23]
RP   VARIANT ASN-639, AND INVOLVEMENT IN SLEB9.
RX   PubMed=17360460; DOI=10.1073/pnas.0609101104;
RA   Wu H., Boackle S.A., Hanvivadhanakul P., Ulgiati D., Grossman J.M., Lee Y.,
RA   Shen N., Abraham L.J., Mercer T.R., Park E., Hebert L.A., Rovin B.H.,
RA   Birmingham D.J., Chang D.-M., Chen C.J., McCurdy D., Badsha H.M.,
RA   Thong B.Y.H., Chng H.H., Arnett F.C., Wallace D.J., Yu C.Y., Hahn B.H.,
RA   Cantor R.M., Tsao B.P.;
RT   "Association of a common complement receptor 2 haplotype with increased
RT   risk of systemic lupus erythematosus.";
RL   Proc. Natl. Acad. Sci. U.S.A. 104:3961-3966(2007).
CC   -!- FUNCTION: Receptor for complement C3, for the Epstein-Barr virus on
CC       human B-cells and T-cells and for HNRNPU (PubMed:7753047). Participates
CC       in B lymphocytes activation (PubMed:7753047).
CC       {ECO:0000269|PubMed:7753047}.
CC   -!- FUNCTION: (Microbial infection) Acts as a receptor for Epstein-Barr
CC       virus. {ECO:0000269|PubMed:2460635}.
CC   -!- SUBUNIT: Interacts (via Sushi domain 1 and 2) with C3 (PubMed:11387479,
CC       PubMed:21527715). Interacts with CD19 (PubMed:1702139). Part of a
CC       complex composed of CD19, CR2/CD21, CD81 and IFITM1/CD225 in the
CC       membrane of mature B-cells (PubMed:1383329). Interacts (via Sushi
CC       domain 1 and 2) with FCER2 (via the C-terminus).
CC       {ECO:0000269|PubMed:11387479, ECO:0000269|PubMed:1383329,
CC       ECO:0000269|PubMed:16172256, ECO:0000269|PubMed:1702139,
CC       ECO:0000269|PubMed:21527715}.
CC   -!- SUBUNIT: (Microbial infection) Interacts with Epstein-Barr virus gp350
CC       protein. {ECO:0000269|PubMed:2460635}.
CC   -!- INTERACTION:
CC       P20023; P01024: C3; NbExp=4; IntAct=EBI-2872467, EBI-905851;
CC   -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000269|PubMed:1383329,
CC       ECO:0000269|PubMed:1702139}; Single-pass type I membrane protein.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing; Named isoforms=4;
CC       Name=A;
CC         IsoId=P20023-1; Sequence=Displayed;
CC       Name=B;
CC         IsoId=P20023-2; Sequence=VSP_001208, VSP_001209;
CC       Name=C;
CC         IsoId=P20023-3; Sequence=VSP_001210;
CC       Name=D;
CC         IsoId=P20023-4; Sequence=VSP_001210, VSP_001211;
CC   -!- TISSUE SPECIFICITY: Mature B-lymphocytes, T-lymphocytes, pharyngeal
CC       epithelial cells, astrocytes and follicular dendritic cells of the
CC       spleen.
CC   -!- DISEASE: Systemic lupus erythematosus 9 (SLEB9) [MIM:610927]: A
CC       chronic, relapsing, inflammatory, and often febrile multisystemic
CC       disorder of connective tissue, characterized principally by involvement
CC       of the skin, joints, kidneys and serosal membranes. It is of unknown
CC       etiology, but is thought to represent a failure of the regulatory
CC       mechanisms of the autoimmune system. The disease is marked by a wide
CC       range of system dysfunctions, an elevated erythrocyte sedimentation
CC       rate, and the formation of LE cells in the blood or bone marrow.
CC       {ECO:0000269|PubMed:17360460}. Note=Disease susceptibility is
CC       associated with variants affecting the gene represented in this entry.
CC   -!- DISEASE: Immunodeficiency, common variable, 7 (CVID7) [MIM:614699]: A
CC       primary immunodeficiency characterized by antibody deficiency,
CC       hypogammaglobulinemia, recurrent bacterial infections and an inability
CC       to mount an antibody response to antigen. The defect results from a
CC       failure of B-cell differentiation and impaired secretion of
CC       immunoglobulins; the numbers of circulating B-cells is usually in the
CC       normal range, but can be low. {ECO:0000269|PubMed:22035880}. Note=The
CC       disease is caused by variants affecting the gene represented in this
CC       entry.
CC   -!- SIMILARITY: Belongs to the receptors of complement activation (RCA)
CC       family. {ECO:0000305}.
CC   -!- SEQUENCE CAUTION:
CC       Sequence=AAA35784.1; Type=Frameshift; Evidence={ECO:0000305};
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DR   EMBL; M26004; AAA35786.1; -; mRNA.
DR   EMBL; M26016; AAB04638.1; -; Genomic_DNA.
DR   EMBL; M24007; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M24008; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M24009; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M24010; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M24011; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26009; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26010; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26011; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26012; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26013; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26014; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; M26015; AAB04638.1; JOINED; Genomic_DNA.
DR   EMBL; Y00649; CAA68674.1; -; mRNA.
DR   EMBL; J03565; AAA35784.1; ALT_FRAME; mRNA.
DR   EMBL; AK223627; BAD97347.1; -; mRNA.
DR   EMBL; AK301496; BAG63007.1; -; mRNA.
DR   EMBL; EF064746; ABK41929.1; -; Genomic_DNA.
DR   EMBL; AL391597; -; NOT_ANNOTATED_CDS; Genomic_DNA.
DR   EMBL; AL691452; -; NOT_ANNOTATED_CDS; Genomic_DNA.
DR   EMBL; BC090937; AAH90937.1; -; mRNA.
DR   EMBL; BC136394; AAI36395.1; -; mRNA.
DR   EMBL; S62696; AAB27186.1; -; mRNA.
DR   CCDS; CCDS1478.1; -. [P20023-1]
DR   CCDS; CCDS31007.1; -. [P20023-3]
DR   PIR; JL0028; PL0009.
DR   RefSeq; NP_001006659.1; NM_001006658.2. [P20023-3]
DR   RefSeq; NP_001868.2; NM_001877.4. [P20023-1]
DR   PDB; 1GHQ; X-ray; 2.04 A; B/C=21-153.
DR   PDB; 1LY2; X-ray; 1.80 A; A=22-148.
DR   PDB; 1W2R; X-ray; -; A=21-153.
DR   PDB; 1W2S; X-ray; -; B=21-153.
DR   PDB; 2ATY; X-ray; -; A/B=21-153.
DR   PDB; 2GSX; X-ray; -; A=21-971.
DR   PDB; 3OED; X-ray; 3.16 A; C/D=20-153.
DR   PDBsum; 1GHQ; -.
DR   PDBsum; 1LY2; -.
DR   PDBsum; 1W2R; -.
DR   PDBsum; 1W2S; -.
DR   PDBsum; 2ATY; -.
DR   PDBsum; 2GSX; -.
DR   PDBsum; 3OED; -.
DR   AlphaFoldDB; P20023; -.
DR   SMR; P20023; -.
DR   BioGRID; 107771; 13.
DR   CORUM; P20023; -.
DR   IntAct; P20023; 2.
DR   STRING; 9606.ENSP00000356024; -.
DR   GlyCosmos; P20023; 11 sites, No reported glycans.
DR   GlyGen; P20023; 13 sites.
DR   iPTMnet; P20023; -.
DR   PhosphoSitePlus; P20023; -.
DR   BioMuta; CR2; -.
DR   DMDM; 215273962; -.
DR   EPD; P20023; -.
DR   MassIVE; P20023; -.
DR   PaxDb; 9606-ENSP00000356024; -.
DR   PeptideAtlas; P20023; -.
DR   ProteomicsDB; 53712; -. [P20023-1]
DR   ProteomicsDB; 53713; -. [P20023-2]
DR   ProteomicsDB; 53714; -. [P20023-3]
DR   ProteomicsDB; 53715; -. [P20023-4]
DR   ABCD; P20023; 1 sequenced antibody.
DR   Antibodypedia; 3624; 1787 antibodies from 49 providers.
DR   DNASU; 1380; -.
DR   Ensembl; ENST00000367057.8; ENSP00000356024.3; ENSG00000117322.19. [P20023-3]
DR   Ensembl; ENST00000367058.7; ENSP00000356025.3; ENSG00000117322.19. [P20023-1]
DR   GeneID; 1380; -.
DR   KEGG; hsa:1380; -.
DR   MANE-Select; ENST00000367057.8; ENSP00000356024.3; NM_001006658.3; NP_001006659.1. [P20023-3]
DR   UCSC; uc001hfv.4; human. [P20023-1]
DR   AGR; HGNC:2336; -.
DR   CTD; 1380; -.
DR   DisGeNET; 1380; -.
DR   GeneCards; CR2; -.
DR   HGNC; HGNC:2336; CR2.
DR   HPA; ENSG00000117322; Tissue enriched (lymphoid).
DR   MalaCards; CR2; -.
DR   MIM; 120650; gene.
DR   MIM; 610927; phenotype.
DR   MIM; 614699; phenotype.
DR   neXtProt; NX_P20023; -.
DR   OpenTargets; ENSG00000117322; -.
DR   Orphanet; 1572; Common variable immunodeficiency.
DR   Orphanet; 536; Systemic lupus erythematosus.
DR   PharmGKB; PA26857; -.
DR   VEuPathDB; HostDB:ENSG00000117322; -.
DR   eggNOG; KOG4297; Eukaryota.
DR   GeneTree; ENSGT00940000161110; -.
DR   HOGENOM; CLU_005124_0_0_1; -.
DR   InParanoid; P20023; -.
DR   OMA; WTQAVPT; -.
DR   OrthoDB; 5395408at2759; -.
DR   PhylomeDB; P20023; -.
DR   TreeFam; TF316872; -.
DR   PathwayCommons; P20023; -.
DR   Reactome; R-HSA-977606; Regulation of Complement cascade.
DR   SignaLink; P20023; -.
DR   SIGNOR; P20023; -.
DR   BioGRID-ORCS; 1380; 11 hits in 1139 CRISPR screens.
DR   ChiTaRS; CR2; human.
DR   EvolutionaryTrace; P20023; -.
DR   GeneWiki; Complement_receptor_2; -.
DR   GenomeRNAi; 1380; -.
DR   Pharos; P20023; Tbio.
DR   PRO; PR:P20023; -.
DR   Proteomes; UP000005640; Chromosome 1.
DR   RNAct; P20023; Protein.
DR   Bgee; ENSG00000117322; Expressed in secondary oocyte and 112 other cell types or tissues.
DR   ExpressionAtlas; P20023; baseline and differential.
DR   Genevisible; P20023; HS.
DR   GO; GO:0070062; C:extracellular exosome; HDA:UniProtKB.
DR   GO; GO:0005615; C:extracellular space; IBA:GO_Central.
DR   GO; GO:0016020; C:membrane; NAS:UniProtKB.
DR   GO; GO:0005886; C:plasma membrane; IBA:GO_Central.
DR   GO; GO:0043235; C:receptor complex; IDA:MGI.
DR   GO; GO:0001848; F:complement binding; IDA:UniProtKB.
DR   GO; GO:0004875; F:complement receptor activity; TAS:ProtInc.
DR   GO; GO:0003677; F:DNA binding; IDA:UniProtKB.
DR   GO; GO:0034987; F:immunoglobulin receptor binding; IDA:UniProtKB.
DR   GO; GO:0042803; F:protein homodimerization activity; IDA:MGI.
DR   GO; GO:0004888; F:transmembrane signaling receptor activity; NAS:UniProtKB.
DR   GO; GO:0001618; F:virus receptor activity; IEA:UniProtKB-KW.
DR   GO; GO:0030183; P:B cell differentiation; IDA:UniProtKB.
DR   GO; GO:0042100; P:B cell proliferation; IDA:UniProtKB.
DR   GO; GO:0006957; P:complement activation, alternative pathway; IMP:ARUK-UCL.
DR   GO; GO:0006958; P:complement activation, classical pathway; IEA:UniProtKB-KW.
DR   GO; GO:0006955; P:immune response; NAS:UniProtKB.
DR   GO; GO:0045959; P:negative regulation of complement activation, classical pathway; IBA:GO_Central.
DR   GO; GO:0002456; P:T cell mediated immunity; IBA:GO_Central.
DR   CDD; cd00033; CCP; 13.
DR   Gene3D; 2.10.70.10; Complement Module, domain 1; 14.
DR   InterPro; IPR035976; Sushi/SCR/CCP_sf.
DR   InterPro; IPR000436; Sushi_SCR_CCP_dom.
DR   PANTHER; PTHR19325; COMPLEMENT COMPONENT-RELATED SUSHI DOMAIN-CONTAINING; 1.
DR   PANTHER; PTHR19325:SF573; SUSHI DOMAIN-CONTAINING PROTEIN; 1.
DR   Pfam; PF00084; Sushi; 13.
DR   SMART; SM00032; CCP; 14.
DR   SUPFAM; SSF57535; Complement control module/SCR domain; 15.
DR   PROSITE; PS50923; SUSHI; 15.
PE   1: Evidence at protein level;
KW   3D-structure; Alternative splicing; Cell membrane; Complement pathway;
KW   Direct protein sequencing; Disulfide bond; Glycoprotein;
KW   Host cell receptor for virus entry; Host-virus interaction; Immunity;
KW   Innate immunity; Membrane; Receptor; Reference proteome; Repeat; Signal;
KW   Sushi; Systemic lupus erythematosus; Transmembrane; Transmembrane helix.
FT   SIGNAL          1..20
FT   CHAIN           21..1033
FT                   /note="Complement receptor type 2"
FT                   /id="PRO_0000006010"
FT   TOPO_DOM        21..971
FT                   /note="Extracellular"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        972..999
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        1000..1033
FT                   /note="Cytoplasmic"
FT                   /evidence="ECO:0000255"
FT   DOMAIN          21..84
FT                   /note="Sushi 1"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          89..148
FT                   /note="Sushi 2"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          152..212
FT                   /note="Sushi 3"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          213..273
FT                   /note="Sushi 4"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          274..344
FT                   /note="Sushi 5"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          349..408
FT                   /note="Sushi 6"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          409..468
FT                   /note="Sushi 7"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          469..524
FT                   /note="Sushi 8"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          525..595
FT                   /note="Sushi 9"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          600..659
FT                   /note="Sushi 10"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          660..716
FT                   /note="Sushi 11"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          717..781
FT                   /note="Sushi 12"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          786..845
FT                   /note="Sushi 13"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          849..909
FT                   /note="Sushi 14"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DOMAIN          910..970
FT                   /note="Sushi 15"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   CARBOHYD        121
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000269|PubMed:12122212,
FT                   ECO:0007744|PDB:1LY2"
FT   CARBOHYD        127
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000269|PubMed:12122212,
FT                   ECO:0007744|PDB:1LY2"
FT   CARBOHYD        294
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        372
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        492
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        623
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000269|PubMed:19349973"
FT   CARBOHYD        682
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        800
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        823
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        861
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        911
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   DISULFID        23..65
FT                   /evidence="ECO:0000269|PubMed:11387479,
FT                   ECO:0000269|PubMed:12122212, ECO:0000269|PubMed:21527715,
FT                   ECO:0007744|PDB:1GHQ, ECO:0007744|PDB:1LY2,
FT                   ECO:0007744|PDB:3OED"
FT   DISULFID        51..82
FT                   /evidence="ECO:0000269|PubMed:11387479,
FT                   ECO:0000269|PubMed:12122212, ECO:0000269|PubMed:21527715,
FT                   ECO:0007744|PDB:1GHQ, ECO:0007744|PDB:1LY2,
FT                   ECO:0007744|PDB:3OED"
FT   DISULFID        91..132
FT                   /evidence="ECO:0000269|PubMed:11387479,
FT                   ECO:0000269|PubMed:12122212, ECO:0000269|PubMed:21527715,
FT                   ECO:0007744|PDB:1GHQ, ECO:0007744|PDB:1LY2,
FT                   ECO:0007744|PDB:3OED"
FT   DISULFID        118..146
FT                   /evidence="ECO:0000269|PubMed:11387479,
FT                   ECO:0000269|PubMed:12122212, ECO:0000269|PubMed:21527715,
FT                   ECO:0007744|PDB:1GHQ, ECO:0007744|PDB:1LY2,
FT                   ECO:0007744|PDB:3OED"
FT   DISULFID        154..197
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        183..210
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        215..256
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        242..271
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        276..325
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        305..342
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        351..393
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        379..406
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        410..453
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        439..466
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        471..509
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        495..522
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        527..576
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        556..593
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        602..644
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        630..657
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        662..699
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        685..714
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        719..762
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        748..779
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        788..830
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        816..843
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        851..894
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        880..907
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        912..955
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   DISULFID        941..968
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00302"
FT   VAR_SEQ         499..524
FT                   /note="Missing (in isoform B)"
FT                   /evidence="ECO:0000303|PubMed:8390533"
FT                   /id="VSP_001208"
FT   VAR_SEQ         525..556
FT                   /note="ITCPPPPVIYNGAHTGSSLEDFPYGTTVTYTC -> NHLPTTPCYLQWGTHR
FT                   EFLRRFSIWNHGHLHM (in isoform B)"
FT                   /evidence="ECO:0000303|PubMed:8390533"
FT                   /id="VSP_001209"
FT   VAR_SEQ         659
FT                   /note="K -> KGCQSPPGLHHGRHTGGNTVFFVSGMTVDYTCDPGYLLVGNKSIHCM
FT                   PSGNWSPSAPRCE (in isoform C and isoform D)"
FT                   /evidence="ECO:0000303|PubMed:10068037,
FT                   ECO:0000303|PubMed:14702039, ECO:0000303|PubMed:15489334,
FT                   ECO:0000303|PubMed:2827171, ECO:0000303|Ref.6"
FT                   /id="VSP_001210"
FT   VAR_SEQ         716..723
FT                   /note="Missing (in isoform D)"
FT                   /evidence="ECO:0000303|PubMed:10068037"
FT                   /id="VSP_001211"
FT   VARIANT         639
FT                   /note="S -> N (in dbSNP:rs17615)"
FT                   /evidence="ECO:0000269|PubMed:15489334,
FT                   ECO:0000269|PubMed:17360460"
FT                   /id="VAR_016164"
FT   VARIANT         993
FT                   /note="I -> V (in dbSNP:rs17618)"
FT                   /evidence="ECO:0000269|PubMed:2832506"
FT                   /id="VAR_016165"
FT   VARIANT         1003
FT                   /note="A -> E (in dbSNP:rs17617)"
FT                   /evidence="ECO:0000269|PubMed:2563370,
FT                   ECO:0000269|PubMed:2827171"
FT                   /id="VAR_016166"
FT   MUTAGEN         103
FT                   /note="R->A: No effect on affinity for C3."
FT                   /evidence="ECO:0000269|PubMed:21527715"
FT   MUTAGEN         112
FT                   /note="D->A: Reduced affinity for C3."
FT                   /evidence="ECO:0000269|PubMed:21527715"
FT   MUTAGEN         128
FT                   /note="K->A: Strongly reduced affinity for C3."
FT                   /evidence="ECO:0000269|PubMed:21527715"
FT   CONFLICT        457
FT                   /note="Missing (in Ref. 2; CAA68674)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        646
FT                   /note="A -> R (in Ref. 3; AAA35784)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        667
FT                   /note="Q -> D (in Ref. 10; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        774
FT                   /note="G -> E (in Ref. 3; AAA35784)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        783..787
FT                   /note="PPVTR -> L (in Ref. 3; AAA35784)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        844
FT                   /note="I -> M (in Ref. 1; AAA35786/AAB04638)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        886
FT                   /note="L -> V (in Ref. 3; AAA35784)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        890
FT                   /note="A -> P (in Ref. 3; AAA35784)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        902
FT                   /note="Q -> G (in Ref. 10; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        906
FT                   /note="H -> L (in Ref. 10; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   STRAND          32..34
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          39..42
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          46..51
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          55..59
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          61..66
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          68..72
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          74..77
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          81..84
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          99..103
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          106..109
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          113..118
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          122..126
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          128..132
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          136..141
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   STRAND          145..148
FT                   /evidence="ECO:0007829|PDB:1LY2"
FT   CONFLICT        P20023-3:663
FT                   /note="S -> P (in Ref. 3; AAA35784)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   1033 AA;  112916 MW;  7D89DB4A07847E9A CRC64;
     MGAAGLLGVF LALVAPGVLG ISCGSPPPIL NGRISYYSTP IAVGTVIRYS CSGTFRLIGE
     KSLLCITKDK VDGTWDKPAP KCEYFNKYSS CPEPIVPGGY KIRGSTPYRH GDSVTFACKT
     NFSMNGNKSV WCQANNMWGP TRLPTCVSVF PLECPALPMI HNGHHTSENV GSIAPGLSVT
     YSCESGYLLV GEKIINCLSS GKWSAVPPTC EEARCKSLGR FPNGKVKEPP ILRVGVTANF
     FCDEGYRLQG PPSSRCVIAG QGVAWTKMPV CEEIFCPSPP PILNGRHIGN SLANVSYGSI
     VTYTCDPDPE EGVNFILIGE STLRCTVDSQ KTGTWSGPAP RCELSTSAVQ CPHPQILRGR
     MVSGQKDRYT YNDTVIFACM FGFTLKGSKQ IRCNAQGTWE PSAPVCEKEC QAPPNILNGQ
     KEDRHMVRFD PGTSIKYSCN PGYVLVGEES IQCTSEGVWT PPVPQCKVAA CEATGRQLLT
     KPQHQFVRPD VNSSCGEGYK LSGSVYQECQ GTIPWFMEIR LCKEITCPPP PVIYNGAHTG
     SSLEDFPYGT TVTYTCNPGP ERGVEFSLIG ESTIRCTSND QERGTWSGPA PLCKLSLLAV
     QCSHVHIANG YKISGKEAPY FYNDTVTFKC YSGFTLKGSS QIRCKADNTW DPEIPVCEKE
     TCQHVRQSLQ ELPAGSRVEL VNTSCQDGYQ LTGHAYQMCQ DAENGIWFKK IPLCKVIHCH
     PPPVIVNGKH TGMMAENFLY GNEVSYECDQ GFYLLGEKKL QCRSDSKGHG SWSGPSPQCL
     RSPPVTRCPN PEVKHGYKLN KTHSAYSHND IVYVDCNPGF IMNGSRVIRC HTDNTWVPGV
     PTCIKKAFIG CPPPPKTPNG NHTGGNIARF SPGMSILYSC DQGYLLVGEA LLLCTHEGTW
     SQPAPHCKEV NCSSPADMDG IQKGLEPRKM YQYGAVVTLE CEDGYMLEGS PQSQCQSDHQ
     WNPPLAVCRS RSLAPVLCGI AAGLILLTFL IVITLYVISK HRARNYYTDT SQKEAFHLEA
     REVYSVDPYN PAS
//
DBGET integrated database retrieval system