ACTP1_URTCR
ID ACTP1_URTCR Reviewed; 221 AA.
AC C9EIC7;
DT 13-JUL-2010, integrated into UniProtKB/Swiss-Prot.
DT 03-NOV-2009, sequence version 1.
DT 03-AUG-2022, entry version 35.
DE RecName: Full=DELTA-actitoxin-Ucs1a {ECO:0000303|PubMed:22683676};
DE Short=DELTA-AITX-Ucs1a {ECO:0000303|PubMed:22683676};
DE AltName: Full=Cytolysin urticinatoxin {ECO:0000303|Ref.1};
DE Short=UcI {ECO:0000303|PubMed:22683676};
DE Flags: Precursor;
OS Urticina crassicornis (Mottled anemone) (Tealia crassicornis).
OC Eukaryota; Metazoa; Cnidaria; Anthozoa; Hexacorallia; Actiniaria;
OC Actiniidae; Urticina.
OX NCBI_TaxID=45621;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RA Razpotnik A., Macek P., Turk T.;
RT "Cloning and characterization of an actinoporin-type toxin from the sea
RT anemone Urticina crassicornis.";
RL Submitted (AUG-2009) to the EMBL/GenBank/DDBJ databases.
RN [2]
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).
RN [3]
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: Pore-forming protein that forms cations-selective hydrophilic
CC pores of around 1 nm and causes hemolysis. Pore formation is a multi-
CC step process that involves specific recognition of membrane
CC sphingomyelin (but neither cholesterol nor phosphatidylcholine) using
CC aromatic rich region and adjacent phosphocholine (POC) binding site,
CC firm binding to the membrane (mainly driven by hydrophobic
CC interactions) accompanied by the transfer of the N-terminal region to
CC the lipid-water interface and finally pore formation after
CC oligomerization of monomers.
CC -!- SUBUNIT: Tetramer in the presence of a lipidic interface. Monomer, in
CC soluble state. {ECO:0000250}.
CC -!- SUBCELLULAR LOCATION: Secreted. Nematocyst. Target cell membrane.
CC Note=Forms an alpha-helical membrane channel in the prey.
CC -!- DOMAIN: The N-terminal region, before the pore is formed, is bound to
CC the lipid membrane. It partitions into the lipid-water interface and
CC stabilizes the monomeric molecule on the membrane. Finally, it
CC traverses the bilayer, thus forming the transmembrane pore.
CC {ECO:0000250|UniProtKB:P61914}.
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 EMBL; GQ848199; ACV95641.1; -; mRNA.
DR AlphaFoldDB; C9EIC7; -.
DR SMR; C9EIC7; -.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0042151; C:nematocyst; IEA:UniProtKB-SubCell.
DR GO; GO:0046930; C:pore complex; IEA:InterPro.
DR GO; GO:0015267; F:channel activity; IEA:InterPro.
DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR GO; GO:0006812; P:cation transport; IEA:InterPro.
DR GO; GO:0044179; P:hemolysis in another organism; IEA:UniProtKB-KW.
DR GO; GO:0046931; P:pore complex assembly; IEA:InterPro.
DR Gene3D; 2.60.270.20; -; 1.
DR InterPro; IPR009104; Anemon_actinoporin-like.
DR InterPro; IPR015926; Cytolysin/lectin.
DR Pfam; PF06369; Anemone_cytotox; 1.
DR SUPFAM; SSF63724; SSF63724; 1.
PE 2: Evidence at transcript level;
KW Cleavage on pair of basic residues; Cytolysis; Hemolysis; Ion transport;
KW Membrane; Nematocyst; Secreted; Signal; Target cell membrane;
KW Target membrane; Toxin; Transmembrane; Transport.
FT SIGNAL 1..19
FT /evidence="ECO:0000255"
FT PROPEP 20..42
FT /evidence="ECO:0000250"
FT /id="PRO_0000395607"
FT CHAIN 43..221
FT /note="DELTA-actitoxin-Ucs1a"
FT /id="PRO_0000395608"
FT REGION 45..54
FT /note="Plays an important role in the hemolytic activity"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT REGION 53..72
FT /note="N-terminal region"
FT /evidence="ECO:0000250|UniProtKB:P61914"
FT REGION 147..162
FT /note="Trp-rich region, which is important for the binding
FT to lipid membrane"
FT /evidence="ECO:0000250|UniProtKB:P61914"
FT MOTIF 186..188
FT /note="Cell attachment site"
FT /evidence="ECO:0000255"
FT BINDING 96
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT BINDING 129
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT BINDING 147
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT BINDING 149
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT BINDING 175
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT BINDING 179
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT BINDING 180
FT /ligand="phosphocholine"
FT /ligand_id="ChEBI:CHEBI:295975"
FT /evidence="ECO:0000250|UniProtKB:P07845"
FT SITE 155
FT /note="Important in the initial contact with the lipid
FT membrane"
FT /evidence="ECO:0000250|UniProtKB:P61914"
FT SITE 202
FT /note="Interacts with the lipid membrane"
FT /evidence="ECO:0000250|UniProtKB:P61914"
SQ SEQUENCE 221 AA; 24381 MW; E7159CECC698DAE6 CRC64;
MNRLIVLCLF VAMIYATIAL PKKEDISNDE RSISVSKVPV KKSVAIAGAV IEGAKLTFGI
LEKILTVLGD INRKIAIGVD NESGREWTAQ NAYFFSGTSD VVLPASVPNT KAFLYNAQKD
RGPVATGVVG VLAYSLSNGN TLGILFSVPY DYNLYSNWWN IKLYKGIKRA DRDMYNDLYY
YAHPHKGDNG WHENSLGFGL KSKGFMTSSG QTILQIRVSR A
