P09232 · PRTB_YEAST
- ProteinCerevisin
- GenePRB1
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids635 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Vacuolar proteinase B involved in protein degradation in the vacuole. Among other substrates, acts on carboxypeptidase Y (cpY/PRC1) to activate it by processing its Pro-peptide. Required for meiosis and spore formation, and for optimal survival in stationary phase.
Miscellaneous
[beta] is the prion form of PrB. In contrast to other prions, [beta] is not the result of a conformational change of the cellular PrB, but distinguishes itself by autoactivation in trans. Usually, PrB is already involved in its own maturation, but PrA plays a critical role. PrpA mutants lack PrB. However, in growth conditions that favor PRB1 expression, PrB activity persists in PrA mutants due to autocleavage of PrB in trans. This condition is stably transmitted to daughter cells in mitosis. [beta] can be cured by growing in PRB1-repressing conditions. Once a cell has lost PrB activity, it remains stably inactive. Thus, there are 2 alternative states, that are chromosomally identical, but phenotypically distinct. Since PrA is able to activate PrB, normal cells always carry the [beta] prion. Its absence and transmission are only observable in the absence of PrA.
Present with 1600 molecules/cell in log phase SD medium.
Catalytic activity
Features
Showing features for active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Active site | 325 | Charge relay system | ||||
Sequence: D | ||||||
Active site | 357 | Charge relay system | ||||
Sequence: H | ||||||
Active site | 519 | Charge relay system | ||||
Sequence: S |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | extracellular space | |
Cellular Component | fungal-type vacuole | |
Cellular Component | fungal-type vacuole lumen | |
Molecular Function | serine-type endopeptidase activity | |
Biological Process | pexophagy | |
Biological Process | protein catabolic process in the vacuole | |
Biological Process | proteolysis | |
Biological Process | sporulation resulting in formation of a cellular spore |
Keywords
- Molecular function
Enzyme and pathway databases
Protein family/group databases
Names & Taxonomy
Protein names
- Recommended nameCerevisin
- EC number
- Alternative names
Gene names
Organism names
- Strains
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Saccharomycotina > Saccharomycetes > Saccharomycetales > Saccharomycetaceae > Saccharomyces
Accessions
- Primary accessionP09232
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
PTM/Processing
Features
Showing features for signal, propeptide, chain, disulfide bond, glycosylation.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Signal | 1-19 | |||||
Sequence: MKLENTLFTLGALGSISAA | ||||||
Propeptide | PRO_0000027136 | 20-280 | ||||
Sequence: LVIPNLENAADHHELINKEDHHERPRKVEFTKDDDEEPSDSEDKEHGKFHKKGRKGQDKESPEFNGKRASGSHGSAHEGGKGMKPKHESSNDDDNDDKKKKPHHKGGCHENKVEEKKMKGKKVKGKKHHEKTLEKGRHHNRLAPLVSTAQFNPDAISKIIPNRYIIVFKRGAPQEEIDFHKENVQQAQLQSVENLSAEDAFFISTKDTSLSTSEAGGIQDSFNIDNLFSGYIGYFTQEIVDLIRQNPLVDFVERDSIVEAT | ||||||
Chain | PRO_0000027137 | 281-?574 | Cerevisin | |||
Sequence: EFDTQNSAPWGLARISHRERLNLGSFNKYLYDDDAGRGVTSYVIDTGVNINHKDFEKRAIWGKTIPLNDEDLDGNGHGTHCAGTIASKHYGVAKNANVVAVKVLRSNGSGTMSDVVKGVEYAAKAHQKEAQEKKKGFKGSTANMSLGGGKSPALDLAVNAAVEVGIHFAVAAGNENQDACNTSPASADKAITVGASTLSDDRAYFSNWGKCVDVFAPGLNILSTYIGSDDATATLSGTSMASPHVAGLLTYFLSLQPGSDSEFFELGQDSLTPQQLKKKLIHYSTKDILFDIPE | ||||||
Disulfide bond | 460↔491 | |||||
Sequence: CNTSPASADKAITVGASTLSDDRAYFSNWGKC | ||||||
Propeptide | PRO_0000417567 | ?575-635 | ||||
Sequence: DTPNVLIYNGGGQDLSAFWNDTKKSHSSGFKQELNMDEFIGSKTDLIFDQVRDILDKLNII | ||||||
Glycosylation | 594 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N |
Post-translational modification
Activated by N- and C-terminal proteolytic cleavage. Protease B (PrB/PRB1) processing requires at least 4 cleavages. First, the signal peptide is removed from the 76 kDa preproprotease B by signal peptidase in the ER. Then, PrB removes its own Pro-region (in trans) at the N-terminus, producing a 39 kDa form before exiting the ER. In the Golgi complex, the C-terminal Post-region of the 40 kDa proprotease B undergoes protease A (PrA/PEP4)-mediated processing to a 37 kDa intermediate, which in turn is quickly processed again by PrB in trans to yield the 31 kDa mature PrB.
Glycosylated. Preproprotease B is a 76 kDa unglycosylated precursor that enters the endoplasmic reticulum (ER), where it receives one Asn-linked and an undetermined number of non-Asn-linked carbohydrate side chains. In the Golgi complex, the 39 kDa form becomes 40 kDa, due to elaboration of the Asn-linked side chain. The ultimate processing step removes a peptide containing the Asn-linked chain. Mature PrB has only non-Asn-linked carbohydrates.
Keywords
- PTM
Proteomic databases
PTM databases
Expression
Induction
Repressed by glucose.
Structure
Family & Domains
Features
Showing features for compositional bias, region, domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 35-53 | Basic and acidic residues | ||||
Sequence: INKEDHHERPRKVEFTKDD | ||||||
Region | 35-155 | Disordered | ||||
Sequence: INKEDHHERPRKVEFTKDDDEEPSDSEDKEHGKFHKKGRKGQDKESPEFNGKRASGSHGSAHEGGKGMKPKHESSNDDDNDDKKKKPHHKGGCHENKVEEKKMKGKKVKGKKHHEKTLEKG | ||||||
Compositional bias | 60-85 | Basic and acidic residues | ||||
Sequence: SEDKEHGKFHKKGRKGQDKESPEFNG | ||||||
Compositional bias | 98-137 | Basic and acidic residues | ||||
Sequence: GGKGMKPKHESSNDDDNDDKKKKPHHKGGCHENKVEEKKM | ||||||
Compositional bias | 138-154 | Basic residues | ||||
Sequence: KGKKVKGKKHHEKTLEK | ||||||
Domain | 182-278 | Inhibitor I9 | ||||
Sequence: RYIIVFKRGAPQEEIDFHKENVQQAQLQSVENLSAEDAFFISTKDTSLSTSEAGGIQDSFNIDNLFSGYIGYFTQEIVDLIRQNPLVDFVERDSIVE | ||||||
Domain | 289-614 | Peptidase S8 | ||||
Sequence: PWGLARISHRERLNLGSFNKYLYDDDAGRGVTSYVIDTGVNINHKDFEKRAIWGKTIPLNDEDLDGNGHGTHCAGTIASKHYGVAKNANVVAVKVLRSNGSGTMSDVVKGVEYAAKAHQKEAQEKKKGFKGSTANMSLGGGKSPALDLAVNAAVEVGIHFAVAAGNENQDACNTSPASADKAITVGASTLSDDRAYFSNWGKCVDVFAPGLNILSTYIGSDDATATLSGTSMASPHVAGLLTYFLSLQPGSDSEFFELGQDSLTPQQLKKKLIHYSTKDILFDIPEDTPNVLIYNGGGQDLSAFWNDTKKSHSSGFKQELNMDEFI |
Sequence similarities
Belongs to the peptidase S8 family.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length635
- Mass (Da)69,621
- Last updated1989-07-01 v1
- ChecksumC346C2B1C7DDDC48
Features
Showing features for compositional bias, sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 35-53 | Basic and acidic residues | ||||
Sequence: INKEDHHERPRKVEFTKDD | ||||||
Compositional bias | 60-85 | Basic and acidic residues | ||||
Sequence: SEDKEHGKFHKKGRKGQDKESPEFNG | ||||||
Compositional bias | 98-137 | Basic and acidic residues | ||||
Sequence: GGKGMKPKHESSNDDDNDDKKKKPHHKGGCHENKVEEKKM | ||||||
Compositional bias | 138-154 | Basic residues | ||||
Sequence: KGKKVKGKKHHEKTLEK | ||||||
Sequence conflict | 622 | in Ref. 4; CAA77886/AAA34495 | ||||
Sequence: F → K |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
M18097 EMBL· GenBank· DDBJ | AAA34901.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U18795 EMBL· GenBank· DDBJ | AAB65027.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
Z11859 EMBL· GenBank· DDBJ | CAA77886.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
M90522 EMBL· GenBank· DDBJ | AAA34495.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
BK006939 EMBL· GenBank· DDBJ | DAA07594.1 EMBL· GenBank· DDBJ | Genomic DNA |