ID   3SA1D_NAJAT             Reviewed;          81 AA.
AC   Q98958; Q91125;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   01-FEB-1997, sequence version 1.
DT   25-MAY-2022, entry version 83.
DE   RecName: Full=Cytotoxin 1d/1e;
DE   AltName: Full=Cardiotoxin-1d/1e;
DE   Flags: Precursor;
OS   Naja atra (Chinese cobra).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC   Serpentes; Colubroidea; Elapidae; Elapinae; Naja.
OX   NCBI_TaxID=8656;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1 AND 2).
RC   TISSUE=Venom gland;
RA   Chu R.C., Yang C.-C.;
RL   Submitted (MAY-1996) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Shows cytolytic activity on many different cells by forming
CC       pore in lipid membranes. In vivo, increases heart rate or kills the
CC       animal by cardiac arrest. In addition, it binds to heparin with high
CC       affinity, interacts with Kv channel-interacting protein 1 (KCNIP1) in a
CC       calcium-independent manner, and binds to integrin alpha-V/beta-3
CC       (ITGAV/ITGB3) with moderate affinity. {ECO:0000250|UniProtKB:P60301,
CC       ECO:0000250|UniProtKB:P60304}.
CC   -!- SUBUNIT: Monomer in solution; Homodimer and oligomer in the presence of
CC       negatively charged lipids forming a pore with a size ranging between 20
CC       and 30 Angstroms. {ECO:0000250|UniProtKB:P60301}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250}. Target cell membrane
CC       {ECO:0000250|UniProtKB:P60301}.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing; Named isoforms=2;
CC       Name=1; Synonyms=Cardiotoxin 1d;
CC         IsoId=Q98958-1; Sequence=Displayed;
CC       Name=2; Synonyms=Cardiotoxin 1e;
CC         IsoId=Q98958-2; Sequence=VSP_009329;
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000305}.
CC   -!- SIMILARITY: Belongs to the snake three-finger toxin family. Short-chain
CC       subfamily. Type IA cytotoxin sub-subfamily. {ECO:0000305}.
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DR   EMBL; U58484; AAB18380.1; -; mRNA.
DR   EMBL; U44727; AAA90960.1; -; mRNA.
DR   AlphaFoldDB; Q98958; -.
DR   SMR; Q98958; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0016020; C:membrane; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   GO; GO:0019835; P:cytolysis; IEA:UniProtKB-KW.
DR   CDD; cd00206; snake_toxin; 1.
DR   Gene3D; 2.10.60.10; -; 1.
DR   InterPro; IPR003572; Cytotoxin_Cobra.
DR   InterPro; IPR003571; Snake_3FTx.
DR   InterPro; IPR045860; Snake_toxin-like_sf.
DR   InterPro; IPR018354; Snake_toxin_con_site.
DR   PRINTS; PR00282; CYTOTOXIN.
DR   SUPFAM; SSF57302; SSF57302; 1.
DR   PROSITE; PS00272; SNAKE_TOXIN; 1.
PE   3: Inferred from homology;
KW   Alternative splicing; Cardiotoxin; Cytolysis; Disulfide bond; Membrane;
KW   Secreted; Signal; Target cell membrane; Target membrane; Toxin.
FT   SIGNAL          1..21
FT                   /evidence="ECO:0000250"
FT   CHAIN           22..81
FT                   /note="Cytotoxin 1d/1e"
FT                   /id="PRO_0000035369"
FT   DISULFID        24..42
FT                   /evidence="ECO:0000250|UniProtKB:P60301"
FT   DISULFID        35..59
FT                   /evidence="ECO:0000250|UniProtKB:P60301"
FT   DISULFID        63..74
FT                   /evidence="ECO:0000250|UniProtKB:P60301"
FT   DISULFID        75..80
FT                   /evidence="ECO:0000250|UniProtKB:P60301"
FT   VAR_SEQ         27
FT                   /note="L -> LTIVCLDLGYTLKCNQL (in isoform 2)"
FT                   /evidence="ECO:0000303|Ref.1"
FT                   /id="VSP_009329"
SQ   SEQUENCE   81 AA;  8992 MW;  B3C52492D2E2597C CRC64;
     MKTLLLTLVV VTIVCLDLGY TLKCNQLIPI ASKTCPAGKN LCYKMFMMSD LTIPVKRGCI
     DVCPKNSLLV KYVCCNTDRC N