Q9USN8 · RQC2_SCHPO
- ProteinRibosome quality control complex subunit 2
- Genemtr1
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids1021 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Key component of the ribosome quality control complex (RQC), a ribosome-associated complex that mediates the extraction of incompletely synthesized nascent chains from stalled ribosomes as well as their ubiquitin-mediated proteasomal degradation. Thereby, frees 60S subunit ribosomes from the stalled translation complex and prevents the accumulation of nascent polypeptide chains that are potentially toxic for the cell. Within the RQC complex, mtr1/rqc2 specifically binds stalled 60S ribosomal subunits by recognizing an exposed, nascent chain-conjugated tRNA moiety and promotes the recruitment of rkr1/ltn1 to stalled 60S subunits. Following binding to stalled 60S ribosomal subunits, mtr1/rqc2 mediates CAT tailing by recruiting alanine- and threonine-charged tRNA to the A-site and directing the elongation of stalled nascent chains independently of mRNA or 40S subunits, leading to non-templated C-terminal Ala and Thr extensions (CAT tails). CAT tails promote the rkr1/ltn1-mediated ubiquitination of incompletely synthesized nascent polypeptides: CAT tailing facilitates rkr1/ltn1-dependent ubiquitination by exposing lysine residues that would otherwise remain buried in the ribosomal exit tunnel. Following ubiquitination, incompletely synthesized nascent polypeptides are recognized by CDC48 and degraded by the proteasome. CAT-tailed proteins tend to aggregate and sequester chaperones and can induce proteotoxic stress; their rkr1/ltn1-dependent ubiquitination and degradation is required to prevent proteotoxic stress.
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 | cytoplasm | |
Cellular Component | cytosol | |
Cellular Component | RQC complex | |
Molecular Function | ribosomal large subunit binding | |
Molecular Function | tRNA binding | |
Biological Process | CAT tailing | |
Biological Process | rescue of stalled ribosome | |
Biological Process | ribosome-associated ubiquitin-dependent protein catabolic process |
Names & Taxonomy
Protein names
- Recommended nameRibosome quality control complex subunit 2
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Taphrinomycotina > Schizosaccharomycetes > Schizosaccharomycetales > Schizosaccharomycetaceae > Schizosaccharomyces
Accessions
- Primary accessionQ9USN8
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
PTM/Processing
Features
Showing features for chain, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000116820 | 1-1021 | Ribosome quality control complex subunit 2 | |||
Sequence: MKQRFSALDIAAIAAELREQVVGCRLNNFYDLNARTFLLKFGKQDAKYSIVIESGFRAHLTKFDRENAPLSGFVTKLRKHIKSRRLTGVSQLGTDRVLVFTFGGGANDQDPDWTYYLVCEFFAAGNVLLLDGHYKILSLLRVVTFDKDQVYAVGQKYNLDKNNLVNDNKSQSTIPHMTAERLNILLDEISTAYASPTSINEPLPDQQLSSSTKPIKVPKPVSLRKALTIRLGEYGNALIEHCLRRSKLDPLFPACQLCADETKKNDLLAAFQEADSILAAVNKPPVKGYIFSLEQALTNAADPQHPEECTTLYEDFHPFQPLQLVQANRKCMEFPTYNECVDEFFSSIEAQKLKKRAHDRLATAERRLESAKEDQARKLQSLQDAQATCALRAQAIEMNPELVEAIISYINSLLNQGMDWLDIEKLIQSQKRRSPVAAAIQIPLKLIKNAVTVFLPNPESVDNSDESSETSDDDLDDSDDDNKVKEGKVSSKFIAVELDLSLGAFANARKQYELRREALIKETKTAEAASKALKSTQRKIEQDLKRSTTADTQRILLGRKTFFFEKFHWFISSEGYLVLGGRDAQQNELLFQKYCNTGDIFVCADLPKSSIIIVKNKNPHDPIPPNTLQQAGSLALASSKAWDSKTVISAWWVRIDEVSKLAPTGEILPTGSFAIRAKKNYLPPTVLIMGYGILWQLDEKSSERRKARRLEMEVVETQGKVSELKMEGTSVTSEDNIQDVVSEVSYNEDTNNQSTPDTTGSDIHIVSEKRGKKGSKVITAKKVSAKERREARRARRQTALEESLKAPISIEDATDPQTILAILKQKKAKKKHAAREMEISSQIPSNDSSNVQTPTAESEIEEDGVSEPISAEVIEDQSRNSEAENEKGLSTEQRDEKKHAKVESFQRQEMPRSLFEEIFFAIDSLTPNPQQQDTVINAVPTFAPYNAMTKFNQKVKVMPGTGKVGKAARESIAYFMKKLPKSSKEAAYLENLKDGEIVAPISVSRLKMVFGSSGNTKKSKK | ||||||
Modified residue | 478 | Phosphoserine | ||||
Sequence: S |
Keywords
- PTM
Proteomic databases
PTM databases
Interaction
Subunit
Component of the ribosome quality control complex (RQC), composed of the E3 ubiquitin ligase rkr1/ltn1, rqc1 and mtr1/rqc2, as well as cdc48 and its ubiquitin-binding cofactors associated with the 60S ribosomal subunit. RQC2 binds to the 40S-binding surface of tRNAs.
Protein-protein interaction databases
Structure
Family & Domains
Features
Showing features for coiled coil, region, compositional bias.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Coiled coil | 348-388 | |||||
Sequence: IEAQKLKKRAHDRLATAERRLESAKEDQARKLQSLQDAQAT | ||||||
Region | 457-484 | Disordered | ||||
Sequence: NPESVDNSDESSETSDDDLDDSDDDNKV | ||||||
Compositional bias | 465-480 | Acidic residues | ||||
Sequence: DESSETSDDDLDDSDD | ||||||
Coiled coil | 507-546 | |||||
Sequence: NARKQYELRREALIKETKTAEAASKALKSTQRKIEQDLKR | ||||||
Coiled coil | 698-727 | |||||
Sequence: DEKSSERRKARRLEMEVVETQGKVSELKME | ||||||
Compositional bias | 746-762 | Polar residues | ||||
Sequence: YNEDTNNQSTPDTTGSD | ||||||
Region | 746-801 | Disordered | ||||
Sequence: YNEDTNNQSTPDTTGSDIHIVSEKRGKKGSKVITAKKVSAKERREARRARRQTALE | ||||||
Compositional bias | 763-800 | Basic and acidic residues | ||||
Sequence: IHIVSEKRGKKGSKVITAKKVSAKERREARRARRQTAL | ||||||
Region | 832-905 | Disordered | ||||
Sequence: HAAREMEISSQIPSNDSSNVQTPTAESEIEEDGVSEPISAEVIEDQSRNSEAENEKGLSTEQRDEKKHAKVESF | ||||||
Compositional bias | 839-859 | Polar residues | ||||
Sequence: ISSQIPSNDSSNVQTPTAESE | ||||||
Compositional bias | 877-905 | Basic and acidic residues | ||||
Sequence: QSRNSEAENEKGLSTEQRDEKKHAKVESF |
Sequence similarities
Belongs to the NEMF family.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length1,021
- Mass (Da)114,240
- Last updated2004-03-29 v2
- Checksum5308EEA9AEC52178
Features
Showing features for compositional bias.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 465-480 | Acidic residues | ||||
Sequence: DESSETSDDDLDDSDD | ||||||
Compositional bias | 746-762 | Polar residues | ||||
Sequence: YNEDTNNQSTPDTTGSD | ||||||
Compositional bias | 763-800 | Basic and acidic residues | ||||
Sequence: IHIVSEKRGKKGSKVITAKKVSAKERREARRARRQTAL | ||||||
Compositional bias | 839-859 | Polar residues | ||||
Sequence: ISSQIPSNDSSNVQTPTAESE | ||||||
Compositional bias | 877-905 | Basic and acidic residues | ||||
Sequence: QSRNSEAENEKGLSTEQRDEKKHAKVESF |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
CU329672 EMBL· GenBank· DDBJ | CAA22870.2 EMBL· GenBank· DDBJ | Genomic DNA |