| IED ID | IndEnz0002004492 |
| Enzyme Type ID | protease004492 |
| Protein Name |
Maurocalcin MCa Maurocalcine |
| Gene Name | |
| Organism | Scorpio palmatus (Israeli golden scorpion) (Scorpio maurus palmatus) |
| Taxonomic Lineage | cellular organisms Eukaryota Opisthokonta Metazoa Eumetazoa Bilateria Protostomia Ecdysozoa Panarthropoda Arthropoda Chelicerata Arachnida Scorpiones Iurida Scorpionoidea Scorpionidae Scorpioninae Scorpio Scorpio palmatus (Israeli golden scorpion) (Scorpio maurus palmatus) |
| Enzyme Sequence | GDCLPHLKLCKENKDCCSKKCKRRGTNIEKRCR |
| Enzyme Length | 33 |
| Uniprot Accession Number | P60254 |
| Absorption | |
| Active Site | |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | |
| Enzyme Function | FUNCTION: This toxin stabilizes ryanodine receptor 1 (RyR1) opening in a long-lasting subconductance state (48%-60% of the full conductance state) (PubMed:10713267, PubMed:12869557, PubMed:27114612). Furthermore, it triggers calcium release from sarcoplasmic vesicles (6.6 nM are enough to induce a sharp release, and 60% of the total calcium is released after toxin (100 nM) addition) probably by acting as a cell-penetrating peptide (CPP) (PubMed:27114612). In addition, it has been shown to dose-dependently stimulate ryanodine binding to RyR1 (EC(50)=12.5-26.4 nM) (PubMed:12869557, PubMed:17291197, PubMed:17888395, PubMed:27114612). It also augments the bell-shaped calcium-[3H]ryanodine binding curve that is maximal at about 10 uM calcium concentration (PubMed:27114612). It binds a different site as ryanodine (PubMed:10713267). It acts synergistically with caffeine (By similarity). In vivo, intracerebroventricular injection into mice causes death (PubMed:10713267). {ECO:0000250|UniProtKB:A0A1L4BJ42, ECO:0000250|UniProtKB:B8QG00, ECO:0000250|UniProtKB:P59868, ECO:0000269|PubMed:10713267, ECO:0000269|PubMed:12869557, ECO:0000269|PubMed:17291197, ECO:0000269|PubMed:17888395, ECO:0000269|PubMed:27114612}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Beta strand (4); Disulfide bond (3); Helix (1); Mutagenesis (16); Peptide (1); Region (1); Site (6) |
| Keywords | 3D-structure;Calcium channel impairing toxin;Direct protein sequencing;Disulfide bond;Ion channel impairing toxin;Knottin;Neurotoxin;Ryanodine-sensitive calcium-release channel impairing toxin;Secreted;Toxin |
| Interact With | |
| Induction | |
| Subcellular Location | SUBCELLULAR LOCATION: Secreted {ECO:0000305|PubMed:10713267}. |
| Modified Residue | |
| Post Translational Modification | PTM: The non-natural D-maurocalcin (a chiral analog of maurocalcin composed of D-amino acids) completely loses the ability to stimulate [3H]ryanodine binding and calcium release. Its protease resistance, combined with its efficient cell penetration at concentrations devoid of cell toxicity, suggests that it should be an excellent vector for in vivo applications. {ECO:0000269|PubMed:20610396}. |
| Signal Peptide | |
| Structure 3D | NMR spectroscopy (1) |
| Cross Reference PDB | 1C6W; |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 3,865 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda |