Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Entry version 70 (29 Sep 2021)
Sequence version 1 (26 Sep 2003)
Previous versions | rss
Add a publicationFeedback
Protein

Imperacalcin

Gene
N/A
Organism
Pandinus imperator (Emperor scorpion)
Status
Reviewed-Annotation score:

Annotation score:5 out of 5

<p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the 'correct annotation' for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
-Experimental evidence at protein leveli <p>This indicates the type of evidence that supports the existence of the protein. Note that the 'protein existence' evidence does not give information on the accuracy or correctness of the sequence(s) displayed.<p><a href='/help/protein_existence' target='_top'>More...</a></p>

<p>This section provides any useful information about the protein, mostly biological knowledge.<p><a href='/help/function_section' target='_top'>More...</a></p>Functioni

This toxin affects the activity of ryanodine receptors 1, 2 and 3 (RyR1, RyR2 and RyR3) (PubMed:1334561, PubMed:9565405, PubMed:11867448).

At lower concentrations the toxin increases full openings of the RyRs, and at higher concentrations it inhibits full openings and induces openings to subconductance levels (30% of the full conductance state) and reduces the number of full conductance openings (PubMed:9565405, PubMed:27114612).

The different actions may be attributed to the toxins binding at different sites on the RyRs, with binding at a high-affinity site mediating the increase in full openings and the induction of subconductance states evoked upon binding to a lower-affinity site (PubMed:14699105).

Furthermore, it triggers calcium release from sarcoplasmic vesicles (11.7 nM are enough to induce a sharp release, and 70% of the total calcium is released after toxin (100 nM) addition) probably by acting as a cell-penetrating peptide (CPP) (PubMed:1334561, PubMed:27114612).

In addition, it has been shown to dose-dependently stimulate ryanodine binding to RyR1 (EC(50)=8.7 nM) (PubMed:27114612).

It also augments the bell-shaped calcium-[3H]ryanodine binding curve that is maximal at about 10 µM calcium concentration (PubMed:27114612).

It binds a different site as ryanodine (PubMed:9565405).

It acts synergistically with caffeine (By similarity).

In vivo, intracerebroventricular injection into mice induces neurotoxic symptoms, followed by death (By similarity).

By similarity4 Publications

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection describes interesting single amino acid sites on the sequence that are not defined in any other subsection. This subsection can be displayed in different sections ('Function', 'PTM / Processing', 'Pathology and Biotech') according to its content.<p><a href='/help/site' target='_top'>More...</a></p>Sitei6Important for stimulation of [3H]ryanodine binding to RYR11 Publication1
Sitei7Essential for stimulation of [3H]ryanodine binding to RYR11 Publication1
Sitei11Important for stimulation of [3H]ryanodine binding to RYR11 Publication1
Sitei30Important for stimulation of [3H]ryanodine binding to RYR11 Publication1
Sitei31Essential for stimulation of [3H]ryanodine binding to RYR11 Publication1
Sitei33Essential for stimulation of [3H]ryanodine binding to RYR11 Publication1

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:<p><a href='/help/gene_ontology' target='_top'>More...</a></p>GO - Molecular functioni

<p>UniProtKB Keywords constitute a <a href="http://www.uniprot.org/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='/help/keywords' target='_top'>More...</a></p>Keywordsi

Molecular functionCalcium channel impairing toxin, Ion channel impairing toxin, Neurotoxin, Ryanodine-sensitive calcium-release channel impairing toxin, Toxin

<p>This section provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.<p><a href='/help/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyi

<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides an exhaustive list of all names of the protein, from commonly used to obsolete, to allow unambiguous identification of a protein.<p><a href='/help/protein_names' target='_top'>More...</a></p>Protein namesi
Recommended name:
Imperacalcin1 Publication
Short name:
IpCa1 Publication
Alternative name(s):
Imperatoxin activator1 Publication
Imperatoxin-A2 Publications
Short name:
IpTxa2 Publications
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides information on the name(s) of the organism that is the source of the protein sequence.<p><a href='/help/organism-name' target='_top'>More...</a></p>OrganismiPandinus imperator (Emperor scorpion)
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section shows the unique identifier assigned by the NCBI to the source organism of the protein. This is known as the 'taxonomic identifier' or 'taxid'.<p><a href='/help/taxonomic_identifier' target='_top'>More...</a></p>Taxonomic identifieri55084 [NCBI]
<p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section contains the taxonomic hierarchical classification lineage of the source organism. It lists the nodes as they appear top-down in the taxonomic tree, with the more general grouping listed first.<p><a href='/help/taxonomic_lineage' target='_top'>More...</a></p>Taxonomic lineageiEukaryotaMetazoaEcdysozoaArthropodaChelicerataArachnidaScorpionesIuridaScorpionoideaScorpionidaePandininaePandinus

<p>This section provides information on the location and the topology of the mature protein in the cell.<p><a href='/help/subcellular_location_section' target='_top'>More...</a></p>Subcellular locationi

Keywords - Cellular componenti

Secreted

<p>This section provides information on the disease(s) and phenotype(s) associated with a protein.<p><a href='/help/pathology_and_biotech_section' target='_top'>More...</a></p>Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the <a href="http://www.uniprot.org/manual/pathology_and_biotech_section">'Pathology and Biotech'</a> section describes the effect of the experimental mutation of one or more amino acid(s) on the biological properties of the protein.<p><a href='/help/mutagen' target='_top'>More...</a></p>Mutagenesisi1G → A: 1.18-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi2D → A: 2.33-fold increase of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi3C → A: Linear IpCa; Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi4L → A: 1.93-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi5P → A: 1.43-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi6H → A: 20.72-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi7L → A: 97.51-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi8K → A: 4.60-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi9R → A: 25.62-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi10C → A: Linear IpCa; Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi11K → A: 6.83-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi13D → A: 3.08-fold increase of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi14N → A: 1.14-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi15D → A: 2.73-fold increase of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi16C → A: Linear IpCa; Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi17C → A: Linear IpCa; Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi18G → A: 1.16-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi19K → A: 4.96-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi20K → A: 16.91-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi21C → A: Linear IpCa; Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi22K → A: 69.92-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi23R → A: 418.48-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi24R → A: Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi25G → A: 23.96-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi26T → A: 11.52-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi27N → A: 20.09-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi29E → A: 2.35-fold increase of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi30K → A: 21.69-fold decrease of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi31R → A: Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi32C → A: Linear IpCa; Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1
Mutagenesisi33R → A: Loss of stimulation of [3H]ryanodine binding to RYR1. 1 Publication1

<p>This section describes post-translational modifications (PTMs) and/or processing events.<p><a href='/help/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the 'PTM / Processing' section describes the position and length of an active peptide in the mature protein.<p><a href='/help/peptide' target='_top'>More...</a></p>PeptideiPRO_00000449491 – 33Imperacalcin1 PublicationAdd BLAST33

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the PTM / Processing":/help/ptm_processing_section section describes the positions of cysteine residues participating in disulfide bonds.<p><a href='/help/disulfid' target='_top'>More...</a></p>Disulfide bondi3 ↔ 171 PublicationImported
Disulfide bondi10 ↔ 211 PublicationImported
Disulfide bondi16 ↔ 321 PublicationImported

Keywords - PTMi

Disulfide bond

Proteomic databases

PRoteomics IDEntifications database

More...
PRIDEi
P59868

<p>This section provides information on the expression of a gene at the mRNA or protein level in cells or in tissues of multicellular organisms.<p><a href='/help/expression_section' target='_top'>More...</a></p>Expressioni

<p>This subsection of the 'Expression' section provides information on the expression of a gene at the mRNA or protein level in cells or in tissues of multicellular organisms. By default, the information is derived from experiments at the mRNA level, unless specified 'at protein level'.<br></br>Examples: <a href="http://www.uniprot.org/uniprot/P92958#expression">P92958</a>, <a href="http://www.uniprot.org/uniprot/Q8TDN4#expression">Q8TDN4</a>, <a href="http://www.uniprot.org/uniprot/O14734#expression">O14734</a><p><a href='/help/tissue_specificity' target='_top'>More...</a></p>Tissue specificityi

Expressed by the venom gland.1 Publication

<p>This section provides information on the tertiary and secondary structure of a protein.<p><a href='/help/structure_section' target='_top'>More...</a></p>Structurei

Secondary structure

133
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details

3D structure databases

Biological Magnetic Resonance Data Bank

More...
BMRBi
P59868

SWISS-MODEL Repository - a database of annotated 3D protein structure models

More...
SMRi
P59868

Database of comparative protein structure models

More...
ModBasei
Search...

Protein Data Bank in Europe - Knowledge Base

More...
PDBe-KBi
Search...

Miscellaneous databases

Relative evolutionary importance of amino acids within a protein sequence

More...
EvolutionaryTracei
P59868

<p>This section provides information on sequence similarities with other proteins and the domain(s) present in a protein.<p><a href='/help/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the 'Family and Domains' section describes a region of interest that cannot be described in other subsections.<p><a href='/help/region' target='_top'>More...</a></p>Regioni8 – 9Important for stimulation of [3H]ryanodine binding to RYR11 Publication2
Regioni19 – 20Important for stimulation of [3H]ryanodine binding to RYR11 Publication2
Regioni22 – 24Essential for stimulation of [3H]ryanodine binding to RYR11 Publication3
Regioni25 – 27Important for stimulation of [3H]ryanodine binding to RYR11 Publication3

<p>This subsection of the 'Family and domains' section provides general information on the biological role of a domain. The term 'domain' is intended here in its wide acceptation, it may be a structural domain, a transmembrane region or a functional domain. Several domains are described in this subsection.<p><a href='/help/domain_cc' target='_top'>More...</a></p>Domaini

The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin.1 Publication

<p>This subsection of the 'Family and domains' section provides information about the sequence similarity with other proteins.<p><a href='/help/sequence_similarities' target='_top'>More...</a></p>Sequence similaritiesi

Belongs to the scorpion calcin family.Curated

Keywords - Domaini

Knottin

Family and domain databases

Integrated resource of protein families, domains and functional sites

More...
InterProi
View protein in InterPro
IPR012632, Scorpion_calcine

Pfam protein domain database

More...
Pfami
View protein in Pfam
PF08099, Toxin_27, 1 hit

PROSITE; a protein domain and family database

More...
PROSITEi
View protein in PROSITE
PS60028, SCORPION_CALCINE, 1 hit

<p>This section displays by default the canonical protein sequence and upon request all isoforms described in the entry. It also includes information pertinent to the sequence(s), including <a href="http://www.uniprot.org/help/sequence_length">length</a> and <a href="http://www.uniprot.org/help/sequences">molecular weight</a>. The information is filed in different subsections. The current subsections and their content are listed below:<p><a href='/help/sequences_section' target='_top'>More...</a></p>Sequencei

<p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is complete or not.<p><a href='/help/sequence_status' target='_top'>More...</a></p>Sequence statusi: Complete.

P59868-1 [UniParc]FASTAAdd to basket
« Hide
        10         20         30 
GDCLPHLKRC KADNDCCGKK CKRRGTNAEK RCR
Length:33
Mass (Da):3,764
Last modified:September 26, 2003 - v1
<p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.</p> <p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.</p> <p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).</p> <p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x<sup>64</sup> + x<sup>4</sup> + x<sup>3</sup> + x + 1. The algorithm is described in the ISO 3309 standard. </p> <p class="publication">Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.<br /> <strong>Cyclic redundancy and other checksums</strong><br /> <a href="http://www.nrbook.com/b/bookcpdf.php">Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993)</a>)</p> Checksum:iD0DF8EFFFE294537
GO

<p>This section provides links to proteins that are similar to the protein sequence(s) described in this entry at different levels of sequence identity thresholds (100%, 90% and 50%) based on their membership in UniProt Reference Clusters (<a href="http://www.uniprot.org/help/uniref">UniRef</a>).<p><a href='/help/similar_proteins_section' target='_top'>More...</a></p>Similar proteinsi

<p>This section is used to point to information related to entries and found in data collections other than UniProtKB.<p><a href='/help/cross_references_section' target='_top'>More...</a></p>Cross-referencesi

3D structure databases

Select the link destinations:

Protein Data Bank Europe

More...
PDBei

Protein Data Bank RCSB

More...
RCSB PDBi

Protein Data Bank Japan

More...
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1IE6NMR-A1-33[»]
BMRBiP59868
SMRiP59868
ModBaseiSearch...
PDBe-KBiSearch...

Proteomic databases

PRIDEiP59868

Miscellaneous databases

EvolutionaryTraceiP59868

Family and domain databases

InterProiView protein in InterPro
IPR012632, Scorpion_calcine
PfamiView protein in Pfam
PF08099, Toxin_27, 1 hit
PROSITEiView protein in PROSITE
PS60028, SCORPION_CALCINE, 1 hit

MobiDB: a database of protein disorder and mobility annotations

More...
MobiDBi
Search...

<p>This section provides general information on the entry.<p><a href='/help/entry_information_section' target='_top'>More...</a></p>Entry informationi

<p>This subsection of the 'Entry information' section provides a mnemonic identifier for a UniProtKB entry, but it is not a stable identifier. Each reviewed entry is assigned a unique entry name upon integration into UniProtKB/Swiss-Prot.<p><a href='/help/entry_name' target='_top'>More...</a></p>Entry nameiCAIMP_PANIM
<p>This subsection of the 'Entry information' section provides one or more accession number(s). These are stable identifiers and should be used to cite UniProtKB entries. Upon integration into UniProtKB, each entry is assigned a unique accession number, which is called 'Primary (citable) accession number'.<p><a href='/help/accession_numbers' target='_top'>More...</a></p>AccessioniPrimary (citable) accession number: P59868
<p>This subsection of the 'Entry information' section shows the date of integration of the entry into UniProtKB, the date of the last sequence update and the date of the last annotation modification ('Last modified'). The version number for both the entry and the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> are also displayed.<p><a href='/help/entry_history' target='_top'>More...</a></p>Entry historyiIntegrated into UniProtKB/Swiss-Prot: September 26, 2003
Last sequence update: September 26, 2003
Last modified: September 29, 2021
This is version 70 of the entry and version 1 of the sequence. See complete history.
<p>This subsection of the 'Entry information' section indicates whether the entry has been manually annotated and reviewed by UniProtKB curators or not, in other words, if the entry belongs to the Swiss-Prot section of UniProtKB (<strong>reviewed</strong>) or to the computer-annotated TrEMBL section (<strong>unreviewed</strong>).<p><a href='/help/entry_status' target='_top'>More...</a></p>Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programAnimal Toxin Annotation Program

<p>This section contains any relevant information that doesn't fit in any other defined sections<p><a href='/help/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousi

Keywords - Technical termi

3D-structure, Direct protein sequencing

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  2. SIMILARITY comments
    Index of protein domains and families
UniProt is an ELIXIR core data resource
Main funding by: National Institutes of Health

We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.

Do not show this banner again