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UniProtKB - P03879 (MBI4_YEAST)

Entry version 149 (23 Feb 2022)
Sequence version 2 (19 Jul 2004)
Previous versions | rss
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Protein

Intron-encoded RNA maturase bI4

Gene

BI4

Organism
Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
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

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.

4 Publications

Miscellaneous

Residues 385 to 638 are sufficient for maturase activity.

<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

  • endonuclease activity Source: InterPro
  • RNA binding Source: SGD
Complete GO annotation on QuickGO ...

GO - Biological processi

Complete GO annotation on QuickGO ...

<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 functionHydrolase
Biological processmRNA processing, mRNA splicing

<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%5Fand%5Ftaxonomy%5Fsection">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:
Intron-encoded RNA maturase bI4
Alternative name(s):
RNA maturase SCbI4
Cleaved into the following 2 chains:
Truncated, nonfunctional cytochrome b
RNA maturase bI4 (EC:3.1.-.-)
<p>This subsection of the <a href="http://www.uniprot.org/help/names%5Fand%5Ftaxonomy%5Fsection">Names and taxonomy</a> section indicates the name(s) of the gene(s) that code for the protein sequence(s) described in the entry. Four distinct tokens exist: 'Name', 'Synonyms', 'Ordered locus names' and 'ORF names'.<p><a href='/help/gene_name' target='_top'>More...</a></p>Gene namesi
Name:BI4
Synonyms:SCBI4
Ordered Locus Names:Q0120
<p>This subsection of the <a href="http://www.uniprot.org/help/names%5Fand%5Ftaxonomy%5Fsection">Names and taxonomy</a> section indicates if the gene coding for the protein originates from the hydrogenosome, the mitochondrion, the nucleomorph, different plastids or a plasmid. The absence of this section means that the gene is located in one of the main chromosomal element(s).<p><a href='/help/encoded_on' target='_top'>More...</a></p>Encoded oniMitochondrion
<p>This subsection of the <a href="http://www.uniprot.org/help/names%5Fand%5Ftaxonomy%5Fsection">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>OrganismiSaccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
<p>This subsection of the <a href="http://www.uniprot.org/help/names%5Fand%5Ftaxonomy%5Fsection">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 identifieri559292 [NCBI]
<p>This subsection of the <a href="http://www.uniprot.org/help/names%5Fand%5Ftaxonomy%5Fsection">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 lineageiEukaryota › Fungi › Dikarya › Ascomycota › Saccharomycotina › Saccharomycetes › Saccharomycetales › Saccharomycetaceae › Saccharomyces ›
<p>This subsection of the <a href="http://www.uniprot.org/help/names%5Fand%5Ftaxonomy%5Fsection">Names and taxonomy</a> section is present for entries that are part of a <a href="http://www.uniprot.org/proteomes">proteome</a>, i.e. of a set of proteins thought to be expressed by organisms whose genomes have been completely sequenced.<p><a href='/help/proteomes_manual' target='_top'>More...</a></p>Proteomesi
  • UP000002311 <p>A UniProt <a href="http://www.uniprot.org/manual/proteomes%5Fmanual">proteome</a> can consist of several components.<br></br>The component name refers to the genomic component encoding a set of proteins.<p><a href='/help/proteome_component' target='_top'>More...</a></p> Componenti: Mitochondrion

Organism-specific databases

Saccharomyces Genome Database

More...SGDi		S000007273, BI4

Eukaryotic Pathogen, Vector and Host Database Resources

More...VEuPathDBi		FungiDB:Q0120

<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

Mitochondrion

<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 extent of a polypeptide chain in the mature protein following processing or proteolytic cleavage.<p><a href='/help/chain' target='_top'>More...</a></p>ChainiPRO_00000140201 – ?Truncated, nonfunctional cytochrome b
ChainiPRO_0000014021? – 638RNA maturase bI4

<p>This subsection of the <a href="http://www.uniprot.org/help/ptm%5Fprocessing%5Fsection">PTM/processing</a> section describes post-translational modifications (PTMs). This subsection <strong>complements</strong> the information provided at the sequence level or describes modifications for which <strong>position-specific data is not yet available</strong>.<p><a href='/help/post-translational_modification' target='_top'>More...</a></p>Post-translational modificationi

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.1 Publication

Proteomic databases

PaxDb, a database of protein abundance averages across all three domains of life

More...PaxDbi		P03879

PRoteomics IDEntifications database

More...PRIDEi		P03879

<p>This section provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.<p><a href='/help/interaction_section' target='_top'>More...</a></p>Interactioni

<p>This subsection of the <a href="http://www.uniprot.org/help/interaction%5Fsection">'Interaction'</a> section provides information about the protein quaternary structure and interaction(s) with other proteins or protein complexes (with the exception of physiological receptor-ligand interactions which are annotated in the <a href="http://www.uniprot.org/help/function%5Fsection">'Function'</a> section).<p><a href='/help/subunit_structure' target='_top'>More...</a></p>Subunit structurei

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

The Biological General Repository for Interaction Datasets (BioGRID)

More...BioGRIDi		34778, 8 interactors

ComplexPortal: manually curated resource of macromolecular complexes

More...ComplexPortali		CPX-1314, bI4 intron splicing factor complex

Protein interaction database and analysis system

More...IntActi		P03879, 1 interactor

STRING: functional protein association networks

More...STRINGi		4932.Q0120

Miscellaneous databases

RNAct, Protein-RNA interaction predictions for model organisms.

More...RNActi		P03879, protein

<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

3D structure databases

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

More...SMRi		P03879

Database of comparative protein structure models

More...ModBasei		Search...

<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>Regioni1 – 253COB exons 1 to 4 encodedAdd BLAST253
Regioni253 – 638COB intron 4 encodedAdd BLAST386

<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

In the C-terminal section; belongs to the LAGLIDADG endonuclease family.Curated

Phylogenomic databases

evolutionary genealogy of genes: Non-supervised Orthologous Groups

More...eggNOGi		KOG4663, Eukaryota

Ensembl GeneTree

More...GeneTreei		ENSGT00390000017948

The HOGENOM Database of Homologous Genes from Fully Sequenced Organisms

More...HOGENOMi		CLU_429071_0_0_1

InParanoid: Eukaryotic Ortholog Groups

More...InParanoidi		P03879

Family and domain databases

Conserved Domains Database

More...CDDi		cd00284, Cytochrome_b_N, 1 hit

Gene3D Structural and Functional Annotation of Protein Families

More...Gene3Di		1.20.810.10, 1 hit
3.10.28.10, 2 hits

Integrated resource of protein families, domains and functional sites

More...InterProi		View protein in InterPro
IPR005797, Cyt_b/b6_N
IPR027387, Cytb/b6-like_sf
IPR016174, Di-haem_cyt_TM
IPR027434, Homing_endonucl
IPR004860, LAGLIDADG_2

Pfam protein domain database

More...Pfami		View protein in Pfam
PF00033, Cytochrome_B, 1 hit
PF00961, LAGLIDADG_1, 2 hits

Superfamily database of structural and functional annotation

More...SUPFAMi		SSF55608, SSF55608, 2 hits
SSF81342, SSF81342, 1 hit

PROSITE; a protein domain and family database

More...PROSITEi		View protein in PROSITE
PS51002, CYTB_NTER, 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%5Flength">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%5Fsection">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical%5Fand%5Fisoforms">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.

<p>This subsection of the <a href="http://www.uniprot.org/help/sequences%5Fsection">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical%5Fand%5Fisoforms">canonical sequence</a> displayed by default in the entry is in its mature form or if it represents the precursor.<p><a href='/help/sequence_processing' target='_top'>More...</a></p>Sequence processingi: The displayed sequence is further processed into a mature form.

P03879-1 [UniParc]FASTAAdd to basket
« Hide
        10         20         30         40         50
MAFRKSNVYL SLVNSYIIDS PQPSSINYWW NMGSLLGLCL VIQIVTGIFM 
        60         70         80         90        100
AMHYSSNIEL AFSSVEHIMR DVHNGYILRY LHANGASFFF MVMFMHMAKG 
       110        120        130        140        150
LYYGSYRSPR VTLWNVGVII FILTIATAFL GYCCVYGQMS HWGATVITNL 
       160        170        180        190        200
FSAIPFVGND IVSWLWGGFS VSNPTIQRFF ALHYLVPFII AAMVIMHLMA 
       210        220        230        240        250
LHIHGSSNPL GITGNLDRIP MHSYFIFKDL VTVFLFMLIL ALFVFYSPNT 
       260        270        280        290        300
LGQNMALLLI TYVINILCAV CWKSLFIKYQ WKIYNKTTYY FIIQNILNTK 
       310        320        330        340        350
QLNNFVLKFN WTKQYNKMNI VSDLFNPNRV KYYYKEDNQQ VTNMNSSNTH 
       360        370        380        390        400
LTSNKKNLLV DTSETTRTTK NKFNYLLNIF NMKKMNQIIT KRHYSIYKDS 
       410        420        430        440        450
NIRFNQWLAG LIDGDGYFCI TKNKYASCEI TVELKDEKML RQIQDKFGGS 
       460        470        480        490        500
VKLRSGVKAI RYRLQNKEGM IKLINAVNGN IRNSKRLVQF NKVCILLNID 
       510        520        530        540        550
FKEPIKLTKD NAWFMGFFDA DGTINYYYSG KLKIRPQLTI SVTNKYLHDV 
       560        570        580        590        600
EYYREVFGGN IYFDKAKNGY FKWSINNKEL HNIFYTYNKS CPSKSNKGKR 
       610        620        630 
LFLIDKFYYL YDLLAFKAPH NTALYKAWLK FNEKWNNN
Length:638
Mass (Da):74,580
Last modified:July 19, 2004 - v2
<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:iE0D89849FF75C858
GO

<p>This subsection of the 'Sequence' section reports difference(s) between the protein sequence shown in the UniProtKB entry and other available protein sequences derived from the same gene.<p><a href='/help/sequence_caution' target='_top'>More...</a></p>Sequence cautioni

The sequence CAA24073 differs from that shown. Reason: Erroneous gene model prediction. COB was not predicted to be expressed alternatively as a fusion with intron 4.Curated
The sequence CAB43023 differs from that shown. Reason: Erroneous gene model prediction. COB was not predicted to be expressed alternatively as a fusion with intron 4.Curated

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
<p>This subsection of the 'Sequence' section reports difference(s) between the canonical sequence (displayed by default in the entry) and the different sequence submissions merged in the entry. These various submissions may originate from different sequencing projects, different types of experiments, or different biological samples. Sequence conflicts are usually of unknown origin.<p><a href='/help/conflict' target='_top'>More...</a></p>Sequence conflicti370K → E in CAB43023 (PubMed:6253454).Curated1
Sequence conflicti390T → L in AAB21125 (PubMed:1310149).Curated1
Sequence conflicti433E → K in AAB21125 (PubMed:1310149).Curated1
Sequence conflicti459A → T in CAB43023 (PubMed:6253454).Curated1
Sequence conflicti465Q → K in AAB21125 (PubMed:1310149).Curated1
Sequence conflicti586T → L in AAB21125 (PubMed:1310149).Curated1

Sequence databases

Select the link destinations:

EMBL nucleotide sequence database

More...EMBLi

GenBank nucleotide sequence database

More...GenBanki

DNA Data Bank of Japan; a nucleotide sequence database

More...DDBJi
Links Updated
V00696 Genomic DNA Translation: CAB43023.1 Sequence problems.
V00696 Genomic DNA Translation: CAA24073.2 Sequence problems.
KP263414 Genomic DNA Translation: AIZ98891.1
S76640 Genomic DNA Translation: AAB21125.2

Protein sequence database of the Protein Information Resource

More...PIRi		S78666, QQBY2M

NCBI Reference Sequences

More...RefSeqi		NP_009316.1, NC_001224.1

Genome annotation databases

Ensembl fungal genome annotation project

More...EnsemblFungii		Q0120_mRNA; Q0120; Q0120

Database of genes from NCBI RefSeq genomes

More...GeneIDi		854582

KEGG: Kyoto Encyclopedia of Genes and Genomes

More...KEGGi		sce:Q0120

<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

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
V00696 Genomic DNA Translation: CAB43023.1 Sequence problems.
V00696 Genomic DNA Translation: CAA24073.2 Sequence problems.
KP263414 Genomic DNA Translation: AIZ98891.1
S76640 Genomic DNA Translation: AAB21125.2
PIRiS78666, QQBY2M
RefSeqiNP_009316.1, NC_001224.1

3D structure databases

SMRiP03879
ModBaseiSearch...

Protein-protein interaction databases

BioGRIDi34778, 8 interactors
ComplexPortaliCPX-1314, bI4 intron splicing factor complex
IntActiP03879, 1 interactor
STRINGi4932.Q0120

Proteomic databases

PaxDbiP03879
PRIDEiP03879

Genome annotation databases

EnsemblFungiiQ0120_mRNA; Q0120; Q0120
GeneIDi854582
KEGGisce:Q0120

Organism-specific databases

SGDiS000007273, BI4
VEuPathDBiFungiDB:Q0120

Phylogenomic databases

eggNOGiKOG4663, Eukaryota
GeneTreeiENSGT00390000017948
HOGENOMiCLU_429071_0_0_1
InParanoidiP03879

Miscellaneous databases

Protein Ontology

More...PROi		PR:P03879
RNActiP03879, protein

Family and domain databases

CDDicd00284, Cytochrome_b_N, 1 hit
Gene3Di1.20.810.10, 1 hit
3.10.28.10, 2 hits
InterProiView protein in InterPro
IPR005797, Cyt_b/b6_N
IPR027387, Cytb/b6-like_sf
IPR016174, Di-haem_cyt_TM
IPR027434, Homing_endonucl
IPR004860, LAGLIDADG_2
PfamiView protein in Pfam
PF00033, Cytochrome_B, 1 hit
PF00961, LAGLIDADG_1, 2 hits
SUPFAMiSSF55608, SSF55608, 2 hits
SSF81342, SSF81342, 1 hit
PROSITEiView protein in PROSITE
PS51002, CYTB_NTER, 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 nameiMBI4_YEAST
<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: P03879
Secondary accession number(s): A0A0A7NYH9, Q02324, Q9ZZW6
<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%5Fand%5Fisoforms">canonical sequence</a> are also displayed.<p><a href='/help/entry_history' target='_top'>More...</a></p>Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 19, 2004
Last modified: February 23, 2022
This is version 149 of the entry and version 2 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 programFungal Protein 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

Reference proteome

Documents

  1. Yeast
    Yeast (Saccharomyces cerevisiae): entries, gene names and cross-references to SGD
  2. SIMILARITY comments
    Index of protein domains and families
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