ID ACTPP_ACTEQ Reviewed; 20 AA. AC P0C1H1; DT 27-JUN-2006, integrated into UniProtKB/Swiss-Prot. DT 27-JUN-2006, sequence version 1. DT 22-FEB-2023, entry version 47. DE RecName: Full=Equinatoxin-1'' {ECO:0000305}; DE AltName: Full=DELTA-actitoxin {ECO:0000305}; DE AltName: Full=Equinatoxin I'' {ECO:0000303|PubMed:10414864}; DE Flags: Fragment; OS Actinia equina (Beadlet anemone). OC Eukaryota; Metazoa; Cnidaria; Anthozoa; Hexacorallia; Actiniaria; OC Actiniidae; Actinia. OX NCBI_TaxID=6106; RN [1] RP PROTEIN SEQUENCE. RX PubMed=10414864; DOI=10.1016/s0041-0101(99)00082-3; RA Anderluh G., Krizaj I., Strukelj B., Gubensek F., Macek P., Pungercar J.; RT "Equinatoxins, pore-forming proteins from the sea anemone Actinia equina, RT belong to a multigene family."; RL Toxicon 37:1391-1401(1999). RN [2] RP AMINO-ACID COMPOSITION, AND TOXIC DOSE. RX PubMed=2903587; DOI=10.1016/0041-0101(88)90183-3; RA Macek P., Lebez D.; RT "Isolation and characterization of three lethal and hemolytic toxins from RT the sea anemone Actinia equina L."; RL Toxicon 26:441-451(1988). RN [3] RP REVIEW. RX PubMed=19268680; DOI=10.1016/j.toxicon.2009.02.026; RA Kristan K.C., Viero G., Dalla Serra M., Macek P., Anderluh G.; RT "Molecular mechanism of pore formation by actinoporins."; RL Toxicon 54:1125-1134(2009). CC -!- FUNCTION: Pore-forming protein that forms cations-selective hydrophilic CC pores of around 1 nm and causes cardiac stimulation and cytolysis. Pore CC formation is a multi-step process that involves specific recognition of CC membrane sphingomyelin (but neither cholesterol nor CC phosphatidylcholine) using aromatic rich region and adjacent CC phosphocholine (POC) binding site, firm binding to the membrane (mainly CC driven by hydrophobic interactions) accompanied by the transfer of the CC N-terminal region to the lipid-water interface and finally pore CC formation after oligomerization of monomers. Cytolytic effects include CC red blood cells hemolysis, platelet aggregation and lysis, cytotoxic CC and cytostatic effects on fibroblasts. Lethality in mammals has been CC ascribed to severe vasospasm of coronary vessels, cardiac arrhythmia, CC and inotropic effects. {ECO:0000250|UniProtKB:P07845}. CC -!- SUBUNIT: Octamer or nonamer in membranes. Monomer in the soluble state. CC {ECO:0000250|UniProtKB:B9W5G6}. CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:B9W5G6}. CC Nematocyst {ECO:0000250|UniProtKB:P07845}. Target cell membrane CC {ECO:0000250|UniProtKB:B9W5G6}. Note=Forms an alpha-helical membrane CC channel in the prey. {ECO:0000250|UniProtKB:B9W5G6}. CC -!- DOMAIN: Composed of a long N-terminal alpha-helix and a core region CC rich in beta-sheet structures. Before the pore formation, the alpha- CC helix binds the lipid membrane, partitions into the lipid-water CC interface and stabilizes the monomeric molecule on the membrane. CC Finally, it traverses the bilayer, thus forming the transmembrane pore. CC {ECO:0000250|UniProtKB:P61914}. CC -!- TOXIC DOSE: LD(50) is 23 ug/kg by intravenous injection into mice. CC {ECO:0000269|PubMed:2903587}. CC -!- SIMILARITY: Belongs to the actinoporin family. Sea anemone subfamily. CC {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 AlphaFoldDB; P0C1H1; -. DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell. DR GO; GO:0016020; C:membrane; IEA:UniProtKB-KW. DR GO; GO:0042151; C:nematocyst; IEA:UniProtKB-SubCell. DR GO; GO:0044218; C:other organism cell membrane; IEA:UniProtKB-KW. DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW. DR GO; GO:0019835; P:cytolysis; IEA:UniProtKB-KW. DR GO; GO:0006811; P:ion transport; IEA:UniProtKB-KW. PE 1: Evidence at protein level; KW Cytolysis; Direct protein sequencing; Ion transport; Membrane; Nematocyst; KW Secreted; Target cell membrane; Target membrane; Toxin; Transmembrane; KW Transport. FT PEPTIDE 1..>20 FT /note="Equinatoxin-1''" FT /id="PRO_0000244624" FT REGION 3..12 FT /note="Plays an important role in the hemolytic activity" FT /evidence="ECO:0000250|UniProtKB:P07845" FT REGION 11..>20 FT /note="N-terminal region" FT /evidence="ECO:0000250|UniProtKB:P61914" FT NON_TER 20 SQ SEQUENCE 20 AA; 1960 MW; FA32B426009FF5FA CRC64; SVAVAGAVIE GATLTFNVLQ //