ID   CM3A_CONMA              Reviewed;          22 AA.
AC   P0C1U2;
DT   05-SEP-2006, integrated into UniProtKB/Swiss-Prot.
DT   05-SEP-2006, sequence version 1.
DT   25-MAY-2022, entry version 38.
DE   RecName: Full=Mu-conotoxin MIIIA {ECO:0000303|PubMed:16533055};
OS   Conus magus (Magical cone).
OC   Eukaryota; Metazoa; Spiralia; Lophotrochozoa; Mollusca; Gastropoda;
OC   Caenogastropoda; Neogastropoda; Conoidea; Conidae; Conus; Pionoconus.
OX   NCBI_TaxID=6492;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], SYNTHESIS, AMIDATION AT CYS-22, AND
RP   PYROGLUTAMATE FORMATION AT GLN-1.
RC   TISSUE=Venom duct;
RX   PubMed=16533055; DOI=10.1021/bi052162j;
RA   Zhang M.-M., Fiedler B., Green B.R., Catlin P., Watkins M., Garrett J.E.,
RA   Smith B.J., Yoshikami D., Olivera B.M., Bulaj G.;
RT   "Structural and functional diversities among mu-conotoxins targeting TTX-
RT   resistant sodium channels.";
RL   Biochemistry 45:3723-3732(2006).
RN   [2]
RP   FUNCTION ON SODIUM CHANNELS, SYNTHESIS, AMIDATION AT CYS-22, AND
RP   PYROGLUTAMATE FORMATION AT GLN-1.
RX   PubMed=21652775; DOI=10.1073/pnas.1107027108;
RA   Wilson M.J., Yoshikami D., Azam L., Gajewiak J., Olivera B.M., Bulaj G.,
RA   Zhang M.M.;
RT   "mu-Conotoxins that differentially block sodium channels Nav1.1 through 1.8
RT   identify those responsible for action potentials in sciatic nerve.";
RL   Proc. Natl. Acad. Sci. U.S.A. 108:10302-10307(2011).
CC   -!- FUNCTION: Mu-conotoxins block voltage-gated sodium channels (Nav). This
CC       synthetic toxin potently blocks rNav1.3/SCN3A. It also moderately
CC       blocks rNav1.1/SCN1A, rNav1.2/SCN2A, rNav1.4/SCN4A, mNav1.6/SCN8A, and
CC       Nav1.7/SCN9A. sodium channels. This block is very slowly reversible.
CC       {ECO:0000269|PubMed:21652775}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000305|PubMed:16533055}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom duct.
CC       {ECO:0000305|PubMed:16533055}.
CC   -!- DOMAIN: The cysteine framework is III (CC-C-C-CC). Classified in the M-
CC       5 branch, since 5 residues stand between the fourth and the fifth
CC       cysteine residues. {ECO:0000305}.
CC   -!- MISCELLANEOUS: Does not inhibit Nav1.5/SCN5A and Nav1.8/SCN10A.
CC       {ECO:0000305|PubMed:21652775}.
CC   -!- SIMILARITY: Belongs to the conotoxin M superfamily. {ECO:0000305}.
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DR   AlphaFoldDB; P0C1U2; -.
DR   ConoServer; 1691; MIIIA.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0017080; F:sodium channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
PE   1: Evidence at protein level;
KW   Amidation; Disulfide bond; Ion channel impairing toxin; Neurotoxin;
KW   Pyrrolidone carboxylic acid; Secreted; Toxin;
KW   Voltage-gated sodium channel impairing toxin.
FT   PEPTIDE         1..22
FT                   /note="Mu-conotoxin MIIIA"
FT                   /id="PRO_0000249201"
FT   MOD_RES         1
FT                   /note="Pyrrolidone carboxylic acid"
FT                   /evidence="ECO:0000305|PubMed:16533055,
FT                   ECO:0000305|PubMed:21652775"
FT   MOD_RES         22
FT                   /note="Cysteine amide"
FT                   /evidence="ECO:0000305|PubMed:16533055,
FT                   ECO:0000305|PubMed:21652775"
FT   DISULFID        3..15
FT                   /evidence="ECO:0000250"
FT   DISULFID        4..21
FT                   /evidence="ECO:0000250"
FT   DISULFID        10..22
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   22 AA;  2398 MW;  F6FEE3650E1493CD CRC64;
     QGCCNVPNGC SGRWCRDHAQ CC