ID   AQN3_PIG                Reviewed;         116 AA.
AC   P24020;
DT   01-MAR-1992, integrated into UniProtKB/Swiss-Prot.
DT   01-MAR-1992, sequence version 1.
DT   25-MAY-2022, entry version 99.
DE   RecName: Full=Carbohydrate-binding protein AQN-3;
DE   AltName: Full=Spermadhesin AQN-3;
DE   AltName: Full=Zona pellucida-binding protein AQN-3;
OS   Sus scrofa (Pig).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Laurasiatheria; Artiodactyla; Suina; Suidae; Sus.
OX   NCBI_TaxID=9823;
RN   [1]
RP   PROTEIN SEQUENCE, DISULFIDE BONDS, METHYLATION AT HIS-85, AND
RP   IDENTIFICATION BY MASS SPECTROMETRY.
RC   TISSUE=Sperm;
RX   PubMed=1936247; DOI=10.1016/0014-5793(91)81097-r;
RA   Sanz L., Calvete J.J., Mann K., Schaefer W., Schmid E.R.,
RA   Toepfer-Petersen E.;
RT   "The amino acid sequence of AQN-3, a carbohydrate-binding protein isolated
RT   from boar sperm. Location of disulphide bridges.";
RL   FEBS Lett. 291:33-36(1991).
RN   [2]
RP   PROTEIN SEQUENCE.
RC   TISSUE=Sperm;
RX   PubMed=8269963; DOI=10.1111/j.1432-1033.1993.tb18426.x;
RA   Calvete J.J., Solis D., Sanz L., Diaz-Maurino T., Schaefer W., Mann K.,
RA   Toepfer-Petersen E.;
RT   "Characterization of two glycosylated boar spermadhesins.";
RL   Eur. J. Biochem. 218:719-725(1993).
RN   [3]
RP   PROTEIN SEQUENCE OF 15-22 AND 79-84.
RX   PubMed=8603690; DOI=10.1016/0014-5793(95)01513-2;
RA   Calvete J.J., Dostalova Z., Sanz L., Adermann K., Thole H.H.,
RA   Toepfer-Petersen E.;
RT   "Mapping the heparin-binding domain of boar spermadhesins.";
RL   FEBS Lett. 379:207-211(1996).
CC   -!- FUNCTION: AQN proteins mediate the binding of boar spermatozoa to
CC       component(s) of the egg's zona pellucida by a carbohydrate-binding
CC       mechanism. AQN proteins are secretory components of the male accessory
CC       glands being coated to the sperm surface at the time of ejaculation.
CC       They possess as well heparin-, serine-protease-inhibitor-binding
CC       capability.
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- PTM: The residue at position 85 was identified as a methylhistidine by
CC       mass spectrometry.
CC   -!- SIMILARITY: Belongs to the spermadhesin family. {ECO:0000305}.
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   PIR; S17567; S17567.
DR   PIR; S39434; S39434.
DR   AlphaFoldDB; P24020; -.
DR   SMR; P24020; -.
DR   PaxDb; P24020; -.
DR   Proteomes; UP000008227; Unplaced.
DR   Proteomes; UP000314985; Unplaced.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0008201; F:heparin binding; IEA:UniProtKB-KW.
DR   GO; GO:0007338; P:single fertilization; IEA:UniProtKB-KW.
DR   CDD; cd00041; CUB; 1.
DR   Gene3D; 2.60.120.290; -; 1.
DR   InterPro; IPR000859; CUB_dom.
DR   InterPro; IPR035914; Sperma_CUB_dom_sf.
DR   InterPro; IPR000124; Spermadhesin.
DR   Pfam; PF00431; CUB; 1.
DR   SMART; SM00042; CUB; 1.
DR   SUPFAM; SSF49854; SSF49854; 1.
DR   PROSITE; PS01180; CUB; 1.
DR   PROSITE; PS00985; SPERMADHESIN_1; 1.
DR   PROSITE; PS00986; SPERMADHESIN_2; 1.
PE   1: Evidence at protein level;
KW   Direct protein sequencing; Disulfide bond; Fertilization; Glycoprotein;
KW   Heparin-binding; Methylation; Reference proteome; Secreted.
FT   CHAIN           1..116
FT                   /note="Carbohydrate-binding protein AQN-3"
FT                   /id="PRO_0000221454"
FT   DOMAIN          9..110
FT                   /note="CUB"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00059"
FT   MOD_RES         85
FT                   /note="Methylhistidine"
FT                   /evidence="ECO:0000305|PubMed:1936247"
FT   CARBOHYD        50
FT                   /note="N-linked (GlcNAc...) asparagine"
FT   DISULFID        9..30
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00059,
FT                   ECO:0000269|PubMed:1936247"
FT   DISULFID        53..74
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00059,
FT                   ECO:0000269|PubMed:1936247"
FT   CONFLICT        79
FT                   /note="F -> T (in Ref. 3; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        85
FT                   /note="H -> S (in Ref. 2; AA sequence)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   116 AA;  12885 MW;  EC83E07A811D9FD3 CRC64;
     AQNKGSDDCG GFLKNYSGWI SYYKALTTNC VWTIEMKPGH KIILQILPLN LTCGKEYLEV
     RDQRAGPDNF LKVCGGTGFV YQSSHNVATV KYSRDSHHPA SSFNVYFYGI PQGAKA