VKT1_ANTEL
ID VKT1_ANTEL Reviewed; 65 AA.
AC P86862;
DT 28-JUN-2011, integrated into UniProtKB/Swiss-Prot.
DT 28-JUN-2011, sequence version 1.
DT 25-MAY-2022, entry version 31.
DE RecName: Full=KappaPI-actitoxin-Ael3a {ECO:0000303|PubMed:22683676};
DE Short=KappaPI-AITX-Ael3a {ECO:0000303|PubMed:22683676};
DE AltName: Full=Kunitz-type serine protease inhibitor APEKTx1 {ECO:0000303|PubMed:21477583};
OS Anthopleura elegantissima (Green aggregating anemone) (Actinia
OS elegantissima).
OC Eukaryota; Metazoa; Cnidaria; Anthozoa; Hexacorallia; Actiniaria;
OC Actiniidae; Anthopleura.
OX NCBI_TaxID=6110;
RN [1]
RP PROTEIN SEQUENCE, FUNCTION, MASS SPECTROMETRY, AND 3D-STRUCTURE MODELING.
RX PubMed=21477583; DOI=10.1016/j.bcp.2011.03.023;
RA Peigneur S., Billen B., Derua R., Waelkens E., Debaveye S., Beress L.,
RA Tytgat J.;
RT "A bifunctional sea anemone peptide with Kunitz type protease and potassium
RT channel inhibiting properties.";
RL Biochem. Pharmacol. 82:81-90(2011).
RN [2]
RP NOMENCLATURE.
RX PubMed=22683676; DOI=10.1016/j.toxicon.2012.05.020;
RA Oliveira J.S., Fuentes-Silva D., King G.F.;
RT "Development of a rational nomenclature for naming peptide and protein
RT toxins from sea anemones.";
RL Toxicon 60:539-550(2012).
CC -!- FUNCTION: Dual-function toxin that inhibits both serine proteases
CC (trypsin Kd=124 nM) and voltage-gated potassium channels rKv1.1/KCNA1
CC (IC(50)=0.9 nM). The activity on the Kv1.1/KCNA1 is selective and
CC reversible. The toxin presumably acts by blocking the channel pore in
CC the open state. {ECO:0000269|PubMed:21477583}.
CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000305|PubMed:21477583}.
CC Nematocyst {ECO:0000305}.
CC -!- MASS SPECTROMETRY: Mass=7468.8; Method=MALDI;
CC Evidence={ECO:0000269|PubMed:21477583};
CC -!- MASS SPECTROMETRY: Mass=7484.8; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:21477583};
CC -!- MISCELLANEOUS: Does not inhibit voltage-gated potassium channels
CC Kv1.2/KCNA2, Kv1.3/KCNA3, Kv1.4/KCNA4, Kv1.5/KCNA5, Kv1.6/KCNA6,
CC Kv2.1/KCNB1, Kv3.1/KCNC1, Kv4.2/KCND2, Kv4.3/KCND3, hERG, Shaker, HCN1,
CC HCN2 and voltage-gated sodium channels Nav1.2/SCN2A, Nav1.3/SCN3A,
CC Nav1.4/SCN4A, Nav1.5/SCN5A, Nav1.6/SCN8A, Nav1.7/SCN9A, Nav1.8/SCN10A
CC and the insect channel DmNav1. {ECO:0000269|PubMed:21477583}.
CC -!- SIMILARITY: Belongs to the venom Kunitz-type family. Sea anemone type 2
CC potassium channel toxin subfamily. {ECO:0000305}.
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DR AlphaFoldDB; P86862; -.
DR SMR; P86862; -.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0042151; C:nematocyst; IEA:UniProtKB-SubCell.
DR GO; GO:0019870; F:potassium channel inhibitor activity; IDA:UniProtKB.
DR GO; GO:0004867; F:serine-type endopeptidase inhibitor activity; IDA:UniProtKB.
DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR CDD; cd00109; KU; 1.
DR Gene3D; 4.10.410.10; -; 1.
DR InterPro; IPR002223; Kunitz_BPTI.
DR InterPro; IPR036880; Kunitz_BPTI_sf.
DR InterPro; IPR020901; Prtase_inh_Kunz-CS.
DR Pfam; PF00014; Kunitz_BPTI; 1.
DR PRINTS; PR00759; BASICPTASE.
DR SMART; SM00131; KU; 1.
DR SUPFAM; SSF57362; SSF57362; 1.
DR PROSITE; PS00280; BPTI_KUNITZ_1; 1.
DR PROSITE; PS50279; BPTI_KUNITZ_2; 1.
PE 1: Evidence at protein level;
KW Direct protein sequencing; Disulfide bond; Ion channel impairing toxin;
KW Nematocyst; Potassium channel impairing toxin; Protease inhibitor;
KW Secreted; Serine protease inhibitor; Toxin;
KW Voltage-gated potassium channel impairing toxin.
FT CHAIN 1..65
FT /note="KappaPI-actitoxin-Ael3a"
FT /evidence="ECO:0000269|PubMed:21477583"
FT /id="PRO_0000409666"
FT DOMAIN 5..55
FT /note="BPTI/Kunitz inhibitor"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00031"
FT SITE 15..16
FT /note="Reactive bond"
FT /evidence="ECO:0000250|UniProtKB:P31713"
FT DISULFID 5..55
FT /evidence="ECO:0000250|UniProtKB:P00974,
FT ECO:0000255|PROSITE-ProRule:PRU00031"
FT DISULFID 14..38
FT /evidence="ECO:0000250|UniProtKB:P00974,
FT ECO:0000255|PROSITE-ProRule:PRU00031"
FT DISULFID 30..51
FT /evidence="ECO:0000250|UniProtKB:P00974,
FT ECO:0000255|PROSITE-ProRule:PRU00031"
SQ SEQUENCE 65 AA; 7475 MW; C1BA102A64817945 CRC64;
INSICLLPKK QGFCRARFPR FYYNSSTRRC EMFYYGGCGG NANNFNTLEE CEKVCLGYGE
AWKAP
