ID   CA11_CONBN              Reviewed;          65 AA.
AC   P0CE73; P0C1Y1;
DT   23-MAR-2010, integrated into UniProtKB/Swiss-Prot.
DT   23-MAR-2010, sequence version 1.
DT   25-MAY-2022, entry version 30.
DE   RecName: Full=Alpha-conotoxin BnIA {ECO:0000303|PubMed:25449095};
DE            Short=Alpha-BnIA {ECO:0000303|PubMed:25449095};
DE   AltName: Full=Alpha-conotoxin-like Bn1.1 {ECO:0000303|PubMed:14701840};
DE   Flags: Precursor;
OS   Conus bandanus (Banded marble cone).
OC   Eukaryota; Metazoa; Spiralia; Lophotrochozoa; Mollusca; Gastropoda;
OC   Caenogastropoda; Neogastropoda; Conoidea; Conidae; Conus; Conus.
OX   NCBI_TaxID=72279;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Venom duct;
RX   PubMed=14701840; DOI=10.1074/jbc.m309654200;
RA   Santos A.D., McIntosh J.M., Hillyard D.R., Cruz L.J., Olivera B.M.;
RT   "The A-superfamily of conotoxins: structural and functional divergence.";
RL   J. Biol. Chem. 279:17596-17606(2004).
RN   [2]
RP   PROTEIN SEQUENCE OF 49-64, AMIDATION AT CYS-64, SUBCELLULAR LOCATION,
RP   DISULFIDE BOND, FUNCTION, AND MASS SPECTROMETRY.
RC   TISSUE=Venom;
RX   PubMed=25449095; DOI=10.1016/j.toxicon.2014.10.006;
RA   Nguyen B., Le Caer J.P., Araoz R., Thai R., Lamthanh H., Benoit E.,
RA   Molgo J.;
RT   "Isolation, purification and functional characterization of alpha-BnIA from
RT   Conus bandanus venom.";
RL   Toxicon 91:155-163(2014).
CC   -!- FUNCTION: Alpha-conotoxins act on postsynaptic membranes, they bind to
CC       the nicotinic acetylcholine receptors (nAChR) and thus inhibit them.
CC       This toxin inhibits acetylcholine-evoked currents reversibly in oocytes
CC       expressing the human alpha-7 nAChR, and blocks nerve-evoked skeletal
CC       muscle contractions in isolated mouse neuromuscular preparations, but
CC       with a very low affinity. {ECO:0000269|PubMed:25449095}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:25449095}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom duct.
CC       {ECO:0000305|PubMed:14701840}.
CC   -!- DOMAIN: The cysteine framework is I (CC-C-C). Alpha4/7 pattern.
CC       {ECO:0000305}.
CC   -!- MASS SPECTROMETRY: Mass=1613.44; Method=MALDI; Note=Monoisotopic mass.;
CC       Evidence={ECO:0000269|PubMed:25449095};
CC   -!- SIMILARITY: Belongs to the conotoxin A superfamily. {ECO:0000305}.
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DR   AlphaFoldDB; P0CE73; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0035792; C:host cell postsynaptic membrane; IEA:UniProtKB-KW.
DR   GO; GO:0030550; F:acetylcholine receptor inhibitor activity; IEA:UniProtKB-KW.
DR   GO; GO:0099106; F:ion channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   InterPro; IPR009958; Conotoxin_a-typ.
DR   Pfam; PF07365; Toxin_8; 1.
PE   1: Evidence at protein level;
KW   Acetylcholine receptor inhibiting toxin; Amidation;
KW   Direct protein sequencing; Disulfide bond; Ion channel impairing toxin;
KW   Neurotoxin; Postsynaptic neurotoxin; Secreted; Signal; Toxin.
FT   SIGNAL          1..21
FT                   /evidence="ECO:0000255"
FT   PROPEP          22..48
FT                   /evidence="ECO:0000250"
FT                   /id="PRO_0000251232"
FT   PEPTIDE         49..64
FT                   /note="Alpha-conotoxin BnIA"
FT                   /evidence="ECO:0000269|PubMed:25449095"
FT                   /id="PRO_0000251233"
FT   REGION          52..54
FT                   /note="Ser-Xaa-Pro motif, crucial for potent interaction
FT                   with nAChR"
FT                   /evidence="ECO:0000250|UniProtKB:P56636"
FT   MOD_RES         64
FT                   /note="Cysteine amide"
FT                   /evidence="ECO:0000269|PubMed:25449095"
FT   DISULFID        50..56
FT                   /evidence="ECO:0000269|PubMed:25449095"
FT   DISULFID        51..64
FT                   /evidence="ECO:0000269|PubMed:25449095"
SQ   SEQUENCE   65 AA;  6798 MW;  2AF0E31D54489134 CRC64;
     MGMRMMFTMF LLVVLATTVV SFASDRASDG RNAAAKDKAS DLVALTVKGC CSHPACSVNN
     PDICG