P03879 · MBI4_YEAST
- ProteinIntron-encoded RNA maturase bI4
- GeneBI4
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids638 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Mitochondrial mRNA maturase required for splicing of intron 4 of the cytochrome b (COB) gene, containing its own coding sequence, and intron 4 in COX1, coding for the related homing endonuclease aI4. In vivo splicing requires in addition the imported mitochondrial leucyl-tRNA synthetase NAM2. Both proteins seem to stimulate the intrinsic ribozyme activity of intron bI4 through binding to and stabilizing specific secondary and tertiary structure elements in the RNA.
Miscellaneous
Residues 385 to 638 are sufficient for maturase activity.
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 | mitochondrion | |
Molecular Function | endonuclease activity | |
Molecular Function | RNA binding | |
Biological Process | Group I intron splicing | |
Biological Process | mitochondrial electron transport, ubiquinol to cytochrome c | |
Biological Process | mitochondrial mRNA processing | |
Biological Process | mRNA processing | |
Biological Process | proton transmembrane transport |
Keywords
- Molecular function
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameIntron-encoded RNA maturase bI4
- Alternative names
- Cleaved into 2 chains
Gene names
Encoded on
- Mitochondrion
Organism names
- Strains
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Saccharomycotina > Saccharomycetes > Saccharomycetales > Saccharomycetaceae > Saccharomyces
Accessions
- Primary accessionP03879
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000014021 | ?-638 | RNA maturase bI4 | |||
Sequence: MAFRKSNVYLSLVNSYIIDSPQPSSINYWWNMGSLLGLCLVIQIVTGIFMAMHYSSNIELAFSSVEHIMRDVHNGYILRYLHANGASFFFMVMFMHMAKGLYYGSYRSPRVTLWNVGVIIFILTIATAFLGYCCVYGQMSHWGATVITNLFSAIPFVGNDIVSWLWGGFSVSNPTIQRFFALHYLVPFIIAAMVIMHLMALHIHGSSNPLGITGNLDRIPMHSYFIFKDLVTVFLFMLILALFVFYSPNTLGQNMALLLITYVINILCAVCWKSLFIKYQWKIYNKTTYYFIIQNILNTKQLNNFVLKFNWTKQYNKMNIVSDLFNPNRVKYYYKEDNQQVTNMNSSNTHLTSNKKNLLVDTSETTRTTKNKFNYLLNIFNMKKMNQIITKRHYSIYKDSNIRFNQWLAGLIDGDGYFCITKNKYASCEITVELKDEKMLRQIQDKFGGSVKLRSGVKAIRYRLQNKEGMIKLINAVNGNIRNSKRLVQFNKVCILLNIDFKEPIKLTKDNAWFMGFFDADGTINYYYSGKLKIRPQLTISVTNKYLHDVEYYREVFGGNIYFDKAKNGYFKWSINNKELHNIFYTYNKSCPSKSNKGKRLFLIDKFYYLYDLLAFKAPHNTALYKAWLKFNEKWNNN | ||||||
Chain | PRO_0000014020 | 1-? | Truncated, nonfunctional cytochrome b |
Post-translational modification
The mature protein may arise from proteolytic cleavage of an in-frame translation of COB exons 1 to 4 plus intron 4, containing the bI4 open reading frame. Cleavage would take place close to the Met-385 resulting in an active maturase of about 30 kDa.
Proteomic databases
Interaction
Subunit
Forms a ternary complex with intron derived RNA and the imported mitochondrial leucyl-tRNA synthetase NAM2. The proteins do not interact directly with each other.
Protein-protein interaction databases
Miscellaneous
Structure
Family & Domains
Features
Showing features for region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 1-253 | COB exons 1 to 4 encoded | ||||
Sequence: MAFRKSNVYLSLVNSYIIDSPQPSSINYWWNMGSLLGLCLVIQIVTGIFMAMHYSSNIELAFSSVEHIMRDVHNGYILRYLHANGASFFFMVMFMHMAKGLYYGSYRSPRVTLWNVGVIIFILTIATAFLGYCCVYGQMSHWGATVITNLFSAIPFVGNDIVSWLWGGFSVSNPTIQRFFALHYLVPFIIAAMVIMHLMALHIHGSSNPLGITGNLDRIPMHSYFIFKDLVTVFLFMLILALFVFYSPNTLGQ | ||||||
Region | 253-638 | COB intron 4 encoded | ||||
Sequence: QNMALLLITYVINILCAVCWKSLFIKYQWKIYNKTTYYFIIQNILNTKQLNNFVLKFNWTKQYNKMNIVSDLFNPNRVKYYYKEDNQQVTNMNSSNTHLTSNKKNLLVDTSETTRTTKNKFNYLLNIFNMKKMNQIITKRHYSIYKDSNIRFNQWLAGLIDGDGYFCITKNKYASCEITVELKDEKMLRQIQDKFGGSVKLRSGVKAIRYRLQNKEGMIKLINAVNGNIRNSKRLVQFNKVCILLNIDFKEPIKLTKDNAWFMGFFDADGTINYYYSGKLKIRPQLTISVTNKYLHDVEYYREVFGGNIYFDKAKNGYFKWSINNKELHNIFYTYNKSCPSKSNKGKRLFLIDKFYYLYDLLAFKAPHNTALYKAWLKFNEKWNNN |
Sequence similarities
In the C-terminal section; belongs to the LAGLIDADG endonuclease family.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length638
- Mass (Da)74,580
- Last updated2004-07-19 v2
- ChecksumE0D89849FF75C858
Sequence caution
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 370 | in Ref. 1; CAB43023 | ||||
Sequence: K → E | ||||||
Sequence conflict | 390 | in Ref. 4; AAB21125 | ||||
Sequence: T → L | ||||||
Sequence conflict | 433 | in Ref. 4; AAB21125 | ||||
Sequence: E → K | ||||||
Sequence conflict | 459 | in Ref. 1; CAB43023 | ||||
Sequence: A → T | ||||||
Sequence conflict | 465 | in Ref. 4; AAB21125 | ||||
Sequence: Q → K | ||||||
Sequence conflict | 586 | in Ref. 4; AAB21125 | ||||
Sequence: T → L |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
V00696 EMBL· GenBank· DDBJ | CAB43023.1 EMBL· GenBank· DDBJ | Genomic DNA | Sequence problems. | |
V00696 EMBL· GenBank· DDBJ | CAA24073.2 EMBL· GenBank· DDBJ | Genomic DNA | Sequence problems. | |
KP263414 EMBL· GenBank· DDBJ | AIZ98891.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
S76640 EMBL· GenBank· DDBJ | AAB21125.2 EMBL· GenBank· DDBJ | Genomic DNA |