DDP1/YOR163W Summary Help

Standard Name DDP1 1
Systematic Name YOR163W
Feature Type ORF, Verified
Description Polyphosphate phosphatase; hydrolyzes diphosphorylated inositol polyphosphates and diadenosine polyphosphates; high specificity for diadenosine hexa- and pentaphosphates; contains endopolyphosphatase activity with a high affinity for polyphosphates, an activity also observed for its human DIPP homologs; possesses mRNA decapping activity; nudix hydrolase family member; protein abundance increases in response to DNA replication stress (2, 3, 4, 5, 6 and see Summary Paragraph)
Name Description Diadenosine and Diphosphoinositol Polyphosphate phosphohydrolase
Chromosomal Location
ChrXV:642741 to 643307 | ORF Map | GBrowse
Gene Ontology Annotations All DDP1 GO evidence and references
  View Computational GO annotations for DDP1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Regulators 6 genes
Classical genetics
Large-scale survey
21 total interaction(s) for 21 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 2
  • Affinity Capture-RNA: 3
  • Biochemical Activity: 1
  • Two-hybrid: 1

Genetic Interactions
  • Dosage Rescue: 2
  • Negative Genetic: 7
  • Positive Genetic: 4
  • Synthetic Rescue: 1

Expression Summary
Length (a.a.) 188
Molecular Weight (Da) 21,572
Isoelectric Point (pI) 8.2
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrXV:642741 to 643307 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..567 642741..643307 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | E.C. | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000005689

DDP1 encodes a polyphosphate phosphatase that hydrolyzes inositol pyrophosphates (PP-IPs) and diadenosine polyphosphates (ApAs) (3, 2). PP-IPs and ApAs are metabolically unrelated classes of signaling molecules that are important for processes such as vacuolar biogenesis, DNA repair, cell wall synthesis, telomere maintenance, phosphate homeostasis, stress responses, cell proliferation, and ion-channel function (reviewed in 1 and 3 and references therein). As a PP-IP phosphatase, Ddp1p dephosphorylates both bis-diphosphoinositol tetrakisphosphate ([PP]2-IP4, IP8) and diphosphoinositol pentakisphosphate (PP-IP5, IP7) down to inositol hexakisphosphate (IP6) (3). As an ApA phosphatase, Ddp1p dephosphorylates diadenosine hexaphosphate (Ap6A) most readily, but can also dephosphorylate diadenosine pentaphosphate (Ap5A), adenosine pentaphosphate (p5A), and adenosine tetraphosphate (p4A) (2).

Ddp1 is a member of the MutT motif (nudix hydrolase) family of enzymes that is conserved from yeast to human (2). Homologs include fission yeast APS1 and human DIPP (2, 3 and references therein).

Last updated: 2008-04-30 Contact SGD

References cited on this page View Complete Literature Guide for DDP1
1) York JD  (2006) Regulation of nuclear processes by inositol polyphosphates. Biochim Biophys Acta 1761(5-6):552-9
2) Cartwright JL and McLennan AG  (1999) The Saccharomyces cerevisiae YOR163w gene encodes a diadenosine 5', 5"'-P1,P6-hexaphosphate (Ap6A) hydrolase member of the MutT motif (Nudix hydrolase) family. J Biol Chem 274(13):8604-10
3) Safrany ST, et al.  (1999) The diadenosine hexaphosphate hydrolases from Schizosaccharomyces pombe and Saccharomyces cerevisiae are homologues of the human diphosphoinositol polyphosphate phosphohydrolase. Overlapping substrate specificities in a MutT-type protein. J Biol Chem 274(31):21735-40
4) Lonetti A, et al.  (2011) Identification of an evolutionarily conserved family of inorganic polyphosphate endopolyphosphatases. J Biol Chem 286(37):31966-74
5) Tkach JM, et al.  (2012) Dissecting DNA damage response pathways by analysing protein localization and abundance changes during DNA replication stress. Nat Cell Biol 14(9):966-76
6) Song MG, et al.  (2013) Multiple Nudix family proteins possess mRNA decapping activity. RNA 19(3):390-9