Q8LAC4 · URH2_ARATH
- ProteinProbable uridine nucleosidase 2
- GeneURH2
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids322 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Involved in pyrimidine breakdown, especially in response to dark stress (PubMed:21599668, PubMed:30787180).
In the presence of URH1, exhibits efficient inosine and xanthosine hydrolytic activities (PubMed:21599668, PubMed:30787180).
Support inosine breakdown especially during the late phase of senescence (PubMed:21235647).
In the presence of URH1, exhibits efficient inosine and xanthosine hydrolytic activities (PubMed:21599668, PubMed:30787180).
Support inosine breakdown especially during the late phase of senescence (PubMed:21235647).
Catalytic activity
- H2O + uridine = D-ribose + uracil
- H2O + xanthosine = D-ribose + xanthine
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
0.06 mM | xanthosine | when in complex with URH2 | ||||
4.3 mM | uridine | when in complex with URH2 | ||||
0.6 mM | inosine | when in complex with URH2 |
kcat is 23.3 sec-1 with xanthosine as substrate (when in complex with URH2) (PubMed:30787180).
kcat is 55.3 sec-1 with uridine as substrate (when in complex with URH2) (PubMed:30787180).
kcat is 42.3 sec-1 with inosine as substrate (when in complex with URH2) (PubMed:30787180).
kcat is 55.3 sec-1 with uridine as substrate (when in complex with URH2) (PubMed:30787180).
kcat is 42.3 sec-1 with inosine as substrate (when in complex with URH2) (PubMed:30787180).
Features
Showing features for active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Active site | 14 | |||||
Sequence: D | ||||||
Active site | 246 | |||||
Sequence: H |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytosol | |
Molecular Function | inosine nucleosidase activity | |
Molecular Function | protein heterodimerization activity | |
Molecular Function | purine nucleosidase activity | |
Molecular Function | UDP-glucosyltransferase activity | |
Molecular Function | uridine nucleosidase activity | |
Molecular Function | xanthosine nucleotidase activity | |
Biological Process | inosine catabolic process | |
Biological Process | leaf senescence |
Keywords
- Molecular function
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameProbable uridine nucleosidase 2
- EC number
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageEukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > eudicotyledons > Gunneridae > Pentapetalae > rosids > malvids > Brassicales > Brassicaceae > Camelineae > Arabidopsis
Accessions
- Primary accessionQ8LAC4
- Secondary accessions
Proteomes
Organism-specific databases
Genome annotation databases
Subcellular Location
Phenotypes & Variants
Disruption phenotype
Normal seedling germination and plant growth and development in standard conditions (PubMed:21599668).
No abnormal levels of nucleoside intermediates (PubMed:21599668).
The roots of the double mutant urh1 urh2 accumulates strong levels of xanthosine (PubMed:21599668, PubMed:30787180).
No abnormal levels of nucleoside intermediates (PubMed:21599668).
The roots of the double mutant urh1 urh2 accumulates strong levels of xanthosine (PubMed:21599668, PubMed:30787180).
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 14 | Abrogated hydrolase activity. | ||||
Sequence: D → A |
Variants
We now provide the "Disease & Variants" viewer in its own tab.
The viewer provides 19 variants from UniProt as well as other sources including ClinVar and dbSNP.
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000394503 | 1-322 | Probable uridine nucleosidase 2 | |||
Sequence: MAIGDRKKIIIDTDPGIDDAMAIFVALNSPEVDVIGLTTIFGNVYTTLATRNALHLLEVAGRTDIPVAEGTHKTFLNDTKLRIADFVHGKDGLGNQNFPPPKGKPIEKSGPEFLVEQAKLCPGEITVVALGPLTNLALAVQLDPEFSKNVGQIVLLGGAFAVNGNVNPASEANIFGDPEAADIVFTCGADIIAVGINVTHQVIMTADDKDKLASSKGKLAQYLCKILDVYYDYHLTAYEIKGVYLHDPATILAAFLPSLFTYTEGVARVQTSGITRGLTLLYNNLKRFEEANEWSDKPTVKVAVTVDAPAVVKLIMDRLMES |
Proteomic databases
Expression
Tissue specificity
Expressed in roots, seedlings and flowers.
Induction
Accumulates during senescence.
Gene expression databases
Structure
Sequence & Isoform
- Sequence statusComplete
This entry describes 2 isoforms produced by Alternative splicing.
Q8LAC4-1
This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
- Name1
- Length322
- Mass (Da)34,668
- Last updated2002-10-01 v1
- ChecksumBB13A4C2004C39AF
Q8LAC4-2
- Name2
- Differences from canonical
- 1-20: Missing
Sequence caution
Features
Showing features for alternative sequence.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Alternative sequence | VSP_039276 | 1-20 | in isoform 2 | |||
Sequence: Missing |
Keywords
- Coding sequence diversity
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AC007153 EMBL· GenBank· DDBJ | AAD30614.1 EMBL· GenBank· DDBJ | Genomic DNA | Sequence problems. | |
CP002684 EMBL· GenBank· DDBJ | AEE27866.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
CP002684 EMBL· GenBank· DDBJ | AEE27867.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
BT002049 EMBL· GenBank· DDBJ | AAN72060.1 EMBL· GenBank· DDBJ | mRNA | ||
BT008720 EMBL· GenBank· DDBJ | AAP42733.1 EMBL· GenBank· DDBJ | mRNA | ||
AY087913 EMBL· GenBank· DDBJ | AAM65464.1 EMBL· GenBank· DDBJ | mRNA |