P0C1H1 · ACTPP_ACTEQ
- ProteinEquinatoxin-1''
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids
- Protein existenceEvidence at protein level
- Annotation score3/5
Function
function
Pore-forming protein that forms cations-selective hydrophilic pores of around 1 nm and causes cardiac stimulation and cytolysis. Pore formation is a multi-step process that involves specific recognition of membrane sphingomyelin (but neither cholesterol nor phosphatidylcholine) using aromatic rich region and adjacent phosphocholine (POC) binding site, firm binding to the membrane (mainly driven by hydrophobic interactions) accompanied by the transfer of the N-terminal region to the lipid-water interface and finally pore formation after oligomerization of monomers. Cytolytic effects include red blood cells hemolysis, platelet aggregation and lysis, cytotoxic and cytostatic effects on fibroblasts. Lethality in mammals has been ascribed to severe vasospasm of coronary vessels, cardiac arrhythmia, and inotropic effects.
GO annotations
all annotations | all molecular function | virus receptor activity | dna binding | rna binding | cytoskeletal motor activity | catalytic activity | gtpase activity | structural molecule activity | transporter activity | cytoskeletal protein binding | lipid binding | cyclase activity | antioxidant activity | oxidoreductase activity | transferase activity | hydrolase activity | lyase activity | isomerase activity | ligase activity | protein tag activity | cargo receptor activity | histone binding | protein folding chaperone | translation regulator activity | nutrient reservoir activity | receptor ligand activity | molecular transducer activity | molecular adaptor activity | toxin activity | cell adhesion mediator activity | molecular function regulator activity | virus coreceptor activity | catalytic activity, acting on a protein | catalytic activity, acting on dna | catalytic activity, acting on rna | molecular carrier activity | transcription regulator activity | general transcription initiation factor activity | molecular sensor activity | molecular sequestering activity | atp-dependent activity | other molecular function | all biological process | mitotic cell cycle | cytokinesis | cytoplasmic translation | immune system process | muscle system process | circulatory system process | renal system process | respiratory system process | carbohydrate metabolic process | generation of precursor metabolites and energy | dna replication | dna repair | dna recombination | chromatin organization | dna-templated transcription | regulation of dna-templated transcription | trna metabolic process | protein folding | protein glycosylation | amino acid metabolic process | modified amino acid metabolic process | lipid metabolic process | vitamin metabolic process | sulfur compound metabolic process | intracellular protein transport | nucleocytoplasmic transport | autophagy | inflammatory response | mitochondrion organization | cytoskeleton organization | microtubule-based movement | peroxisome organization | lysosome organization | chromosome segregation | cell adhesion | establishment or maintenance of cell polarity | programmed cell death | photosynthesis | mrna metabolic process | snrna metabolic process | vesicle-mediated transport | reproductive process | digestive system process | signaling | cell differentiation | protein catabolic process | extracellular matrix organization | regulatory ncrna-mediated gene silencing | telomere organization | cell junction organization | wound healing | ribosome biogenesis | cilium organization | anatomical structure development | cell motility | nervous system process | endocrine process | protein maturation | transmembrane transport | nucleobase-containing small molecule metabolic process | hepaticobiliary system process | membrane organization | protein-containing complex assembly | cell wall organization or biogenesis | nitrogen cycle metabolic process | protein localization to plasma membrane | defense response to other organism | detoxification | meiotic nuclear division | mitotic nuclear division | mitochondrial gene expression | carbohydrate derivative metabolic process | other biological process | all cellular component | nuclear chromosome | extracellular region | extracellular space | cell wall | nucleus | nuclear envelope | nucleoplasm | chromosome | nucleolus | mitochondrion | lysosome | endosome | vacuole | peroxisome | endoplasmic reticulum | golgi apparatus | lipid droplet | microtubule organizing center | cytosol | ribosome | cytoskeleton | plasma membrane | cilium | plastid | thylakoid | external encapsulating structure | extracellular matrix | cytoplasmic vesicle | organelle | other cellular component | |||
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Aspect | Term | |
---|---|---|
Cellular Component | extracellular region | |
Cellular Component | membrane | |
Cellular Component | nematocyst | |
Cellular Component | other organism cell membrane | |
Molecular Function | toxin activity | |
Biological Process | killing of cells of another organism | |
Biological Process | monoatomic ion transport |
Keywords
- Molecular function
- Biological process
Names & Taxonomy
Protein names
- Recommended nameEquinatoxin-1''
- Alternative names
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Cnidaria > Anthozoa > Hexacorallia > Actiniaria > Actiniidae > Actinia
Accessions
- Primary accessionP0C1H1
Subcellular Location
UniProt Annotation
GO Annotation
Note: Forms an alpha-helical membrane channel in the prey.
Keywords
- Cellular component
Phenotypes & Variants
Toxic dose
LD50 is 23 ug/kg by intravenous injection into mice.
PTM/Processing
Features
Showing features for peptide.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Peptide | PRO_0000244624 | 1-20 | Equinatoxin-1'' | |||
Sequence: SVAVAGAVIEGATLTFNVLQ |
Interaction
Subunit
Octamer or nonamer in membranes. Monomer in the soluble state.
Structure
Family & Domains
Features
Showing features for region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 3-12 | Plays an important role in the hemolytic activity | ||||
Sequence: AVAGAVIEGA | ||||||
Region | 11-20 | N-terminal region | ||||
Sequence: GATLTFNVLQ |
Domain
Composed of a long N-terminal alpha-helix and a core region rich in beta-sheet structures. Before the pore formation, the alpha-helix binds the lipid membrane, partitions into the lipid-water interface and stabilizes the monomeric molecule on the membrane. Finally, it traverses the bilayer, thus forming the transmembrane pore.
Sequence similarities
Belongs to the actinoporin family. Sea anemone subfamily.
Keywords
- Domain
Family and domain databases
Sequence
- Sequence statusFragment
- Length20
- Mass (Da)1,960
- Last updated2006-06-27 v1
- ChecksumFA32B426009FF5FA
Features
Showing features for non-terminal residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Non-terminal residue | 20 | |||||
Sequence: Q |
Keywords
- Technical term