| IED ID | IndEnz0002010502 |
| Enzyme Type ID | protease010502 |
| Protein Name |
Structural polyprotein PP Cleaved into: Precursor of VP2 Pre-VP2 ; Capsid protein VP2; Structural peptide 1 p1 ; Structural peptide 2 p2 ; Structural peptide 3 p3 ; Structural peptide 4 p4 ; Protein X; Protease VP4 EC 3.4.21.- Non-structural protein VP4 NS ; Capsid protein VP3 |
| Gene Name | |
| Organism | Blotched snakehead virus (BSNV) (Channa lucius virus) |
| Taxonomic Lineage | Viruses Riboviria Orthornavirae Birnaviridae Blosnavirus Blotched snakehead virus (BSNV) (Channa lucius virus) |
| Enzyme Sequence | MDFSKENTQIRYLNSLLVPETGSTSIPDDTLDRHCLKTETTTENLVAALGGSGLIVLFPNSPSGLLGAHYTKTPQGSLIFDKAITTSQDLKKAYNYARLVSRIVQVRSSTLPAGVYALNGTFNGVTYIGSLSEIKDLDYNSLLSATANINDKVGNVLVGDGVAVLSLPAGSDLPYVRLGDEVPSSAGVARCSPSDRPRHYNANNKQVQVGTTDTKTNGFNIDATTPTEVTVDMQIAQIAAGKTLTVTVKLMGLTGAKVASRSETVSGNGGTFHFSTTAVFGETEITQPVVGVQVLAKTNGDPIVVDSYVGVTVHGGNMPGTLRPVTIIAYESVATGSVLTLSGISNYELIPNPELAKNIQTSYGKLNPAEMTYTKVVLSHRDELGLRSIWSIPQYRDMMSYFREVSDRSSPLKIAGAFGWGDLLSGIRKWVFPVVDTLLPAARPLTDLASGWIKNKYPEAASGRPLAASGRPMAASGTFSKRIPLASSDEIDYQSVLALTIPGTHPKLVPPTEREPNSTPDGHKITGAKTKDNTGGDVTVVKPLDWLFKLPCLRPQAADLPISLLQTLAYKQPLGRNSRIVHFTDGALFPVVAFGDNHSTSELYIAVRGDHRDLMSPDVRDSYALTGDDHKVWGATHHTYYVEGAPKKPLKFNVKTRTDLTILPVADVFWRADGSADVDVVWNDMPAVAGQSSSIALALASSLPFVPKAAYTGCLSGTNVQPVQFGNLKARAAHKIGLPLVGMTQDGGEDTRICTLDDAADHAFDSMESTVTRPESVGHQAAFQGWFYCGAADEETIEELEDFLDSIELHSKPTVEQPQTEEAMELLMELARKDPQMSKILVILGWVEGAGLIDALYNWAQLDDGGVRMRNMLRNLPHEGSKSQRRKHGPAPESRESTRMEVLRREAAAKRKKAQRISEDAMDNGFEFATIDWVLENGSRGPNPAQAKYYKATGLDPEPGLTEFLPEPTHAPENKAAKLAATIYGSPNQAPAPPEFVEEVAAVLMENNGRGPNQAQMRELRLKALTMKSGSGAAATFKPRNRRPAQEYQPRPPITSRAGRFLNISTTLS |
| Enzyme Length | 1069 |
| Uniprot Accession Number | Q8AZM0 |
| Absorption | |
| Active Site | ACT_SITE 692; /note="Nucleophile"; /evidence="ECO:0000255|PROSITE-ProRule:PRU00881, ECO:0000269|PubMed:12477876"; ACT_SITE 729; /evidence="ECO:0000255|PROSITE-ProRule:PRU00881, ECO:0000269|PubMed:12477876" |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | 3.4.21.- |
| Enzyme Function | FUNCTION: Capsid protein VP2 self assembles to form an icosahedral capsid with a T=13 symmetry, about 70 nm in diameter, and consisting of 260 VP2 trimers. The capsid encapsulates the genomic dsRNA. VP2 is also involved in attachment and entry into the host cell (By similarity). {ECO:0000250}.; FUNCTION: The precursor of VP2 plays an important role in capsid assembly. First, pre-VP2 and VP2 oligomers assemble to form a procapsid. Then, the pre-VP2 intermediates may be processed into VP2 proteins by proteolytic cleavage mediated by VP4 to obtain the mature virion. The final capsid is composed of pentamers and hexamers but VP2 has a natural tendency to assemble into all-pentameric structures. Therefore pre-VP2 may be required to allow formation of the hexameric structures (By similarity). {ECO:0000250}.; FUNCTION: Protease VP4 is a serine protease that cleaves the polyprotein into its final products. Pre-VP2 is first partially cleaved, and may be completely processed by VP4 upon capsid maturation. {ECO:0000255|PROSITE-ProRule:PRU00881}.; FUNCTION: Capsid protein VP3 plays a key role in virion assembly by providing a scaffold for the capsid made of VP2. May self-assemble to form a T=4-like icosahedral inner-capsid composed of at least 180 trimers. Plays a role in genomic RNA packaging by recruiting VP1 into the capsid and interacting with the dsRNA genome segments to form a ribonucleoprotein complex. Additionally, the interaction of the VP3 C-terminal tail with VP1 removes the inherent structural blockade of the polymerase active site. Thus, VP3 can also function as a transcriptional activator (By similarity). {ECO:0000250}.; FUNCTION: Structural peptide 1 is a small peptide derived from pre-VP2 C-terminus. It destabilizes and perforates cell membranes, suggesting a role during entry (By similarity). {ECO:0000250}.; FUNCTION: Structural peptide 2 is a small peptide derived from pre-VP2 C-terminus. It is not essential for the virus viability, but viral growth is affected when missing (By similarity). {ECO:0000250}.; FUNCTION: Structural peptide 3 is a small peptide derived from pre-VP2 C-terminus. It is not essential for the virus viability, but viral growth is affected when missing (By similarity). {ECO:0000250}.; FUNCTION: Structural peptide 4 is a small peptide derived from pre-VP2 C-terminus. It is essential for the virus viability (By similarity). {ECO:0000250}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Active site (2); Beta strand (14); Chain (6); Compositional bias (1); Domain (1); Helix (5); Metal binding (1); Mutagenesis (2); Peptide (4); Region (3); Site (7); Turn (1) |
| Keywords | 3D-structure;Capsid protein;Direct protein sequencing;Host cytoplasm;Hydrolase;Metal-binding;Protease;Reference proteome;Serine protease;T=13 icosahedral capsid protein;Virion |
| Interact With | |
| Induction | |
| Subcellular Location | SUBCELLULAR LOCATION: [Capsid protein VP2]: Virion {ECO:0000305}. Host cytoplasm {ECO:0000305}.; SUBCELLULAR LOCATION: [Capsid protein VP3]: Virion {ECO:0000305}. Host cytoplasm {ECO:0000305}.; SUBCELLULAR LOCATION: [Structural peptide 1]: Virion {ECO:0000305}. Host cytoplasm {ECO:0000305}.; SUBCELLULAR LOCATION: [Structural peptide 2]: Virion {ECO:0000305}. Host cytoplasm {ECO:0000305}.; SUBCELLULAR LOCATION: [Structural peptide 3]: Virion {ECO:0000305}. Host cytoplasm {ECO:0000305}.; SUBCELLULAR LOCATION: [Structural peptide 4]: Virion {ECO:0000305}. Host cytoplasm {ECO:0000305}. |
| Modified Residue | |
| Post Translational Modification | PTM: Specific enzymatic cleavages yield mature proteins. The capsid assembly seems to be regulated by polyprotein processing. The protease VP4 cleaves itself off the polyprotein, thus releasing pre-VP2 and VP3 within the infected cell. During capsid assembly, the C-terminus of pre-VP2 is further processed by VP4, giving rise to VP2, the external capsid protein and three small peptides that all stay closely associated with the capsid (By similarity). {ECO:0000250}.; PTM: The N-termini of VP2 and VP3 are blocked. |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (1) |
| Cross Reference PDB | 2GEF; |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 115,494 |
| Kinetics | |
| Metal Binding | METAL 28; /note=Divalent metal cation; shared with trimeric partners; /evidence=ECO:0000250 |
| Rhea ID | |
| Cross Reference Brenda | 3.4.21.115; |