Q8LAC4 · URH2_ARATH

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).

Catalytic activity

Kinetics

KM SUBSTRATE pH TEMPERATURE[C] NOTES EVIDENCE
0.06 mMxanthosinewhen in complex with URH2
4.3 mMuridinewhen in complex with URH2
0.6 mMinosinewhen 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).

Features

Showing features for active site.

TypeIDPosition(s)Description
Active site14
Active site246

GO annotations

AspectTerm
Cellular Componentcytosol
Molecular Functioninosine nucleosidase activity
Molecular Functionprotein heterodimerization activity
Molecular Functionpurine nucleosidase activity
Molecular FunctionUDP-glucosyltransferase activity
Molecular Functionuridine nucleosidase activity
Molecular Functionxanthosine nucleotidase activity
Biological Processinosine catabolic process
Biological Processleaf senescence

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Probable uridine nucleosidase 2
  • EC number
  • Alternative names
    • Inosine nucleosidase
      (EC:3.2.2.2
      ) . EC:3.2.2.2 (UniProtKB | ENZYME | Rhea)
    • Nucleoside hydrolase 2
    • Uridine ribohydrolase 2
    • Xanthosine nucleosidase
      (EC:3.2.2.-
      ) . EC:3.2.2.- (UniProtKB | ENZYME | Rhea)

Gene names

    • Name
      URH2
    • Synonyms
      NSH2
    • ORF names
      F3F20.7
    • Ordered locus names
      At1g05620

Organism names

  • Taxonomic identifier
  • Strain
    • cv. Columbia
  • Taxonomic lineage
    Eukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > eudicotyledons > Gunneridae > Pentapetalae > rosids > malvids > Brassicales > Brassicaceae > Camelineae > Arabidopsis

Accessions

  • Primary accession
    Q8LAC4
  • Secondary accessions
    • B3H6Y7
    • Q9SYK3

Proteomes

Organism-specific databases

Genome annotation databases

Subcellular Location

Keywords

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).

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis14Abrogated hydrolase activity.

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.

Go to variant viewer

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00003945031-322Probable uridine nucleosidase 2

Proteomic databases

Expression

Tissue specificity

Expressed in roots, seedlings and flowers.

Induction

Accumulates during senescence.

Gene expression databases

Interaction

Subunit

Component of the NSH heterocomplex made of URH1/NSH1 and URH2/NSH2 which exhibits strong xanthosine nucleosidase activity (PubMed:30787180).
Interacts with URH1 (PubMed:30787180).

Protein-protein interaction databases

Structure

Family & Domains

Sequence similarities

Belongs to the IUNH family.

Phylogenomic databases

Family and domain databases

Sequence & Isoform

Align isoforms (2)
  • Sequence status
    Complete

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.

  • Length
    322
  • Mass (Da)
    34,668
  • Last updated
    2002-10-01 v1
  • Checksum
    BB13A4C2004C39AF
MAIGDRKKIIIDTDPGIDDAMAIFVALNSPEVDVIGLTTIFGNVYTTLATRNALHLLEVAGRTDIPVAEGTHKTFLNDTKLRIADFVHGKDGLGNQNFPPPKGKPIEKSGPEFLVEQAKLCPGEITVVALGPLTNLALAVQLDPEFSKNVGQIVLLGGAFAVNGNVNPASEANIFGDPEAADIVFTCGADIIAVGINVTHQVIMTADDKDKLASSKGKLAQYLCKILDVYYDYHLTAYEIKGVYLHDPATILAAFLPSLFTYTEGVARVQTSGITRGLTLLYNNLKRFEEANEWSDKPTVKVAVTVDAPAVVKLIMDRLMES

Q8LAC4-2

  • Name
    2
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical

Sequence caution

The sequence AAD30614.1 differs from that shown. Reason: Erroneous gene model prediction

Features

Showing features for alternative sequence.

TypeIDPosition(s)Description
Alternative sequenceVSP_0392761-20in isoform 2

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
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

Genome annotation databases

Similar Proteins

Disclaimer

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