IPK1/YDR315C Summary Help

Standard Name IPK1 1
Systematic Name YDR315C
Alias GSL1
Feature Type ORF, Verified
Description Inositol 1,3,4,5,6-pentakisphosphate 2-kinase; nuclear protein required for synthesis of 1,2,3,4,5,6-hexakisphosphate (phytate), which is integral to cell function; has 2 motifs conserved in other fungi; ipk1 gle1 double mutant is inviable (1, 2 and see Summary Paragraph)
Name Description Inositol Polyphosphate Kinase 1
Chromosomal Location
ChrIV:1093586 to 1092741 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All IPK1 GO evidence and references
  View Computational GO annotations for IPK1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Classical genetics
Large-scale survey
317 total interaction(s) for 239 unique genes/features.
Physical Interactions
  • Affinity Capture-RNA: 2
  • Two-hybrid: 4

Genetic Interactions
  • Dosage Lethality: 1
  • Dosage Rescue: 2
  • Negative Genetic: 218
  • Phenotypic Enhancement: 4
  • Positive Genetic: 66
  • Synthetic Growth Defect: 7
  • Synthetic Lethality: 12
  • Synthetic Rescue: 1

Expression Summary
Length (a.a.) 281
Molecular Weight (Da) 32,918
Isoelectric Point (pI) 7.82
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrIV:1093586 to 1092741 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..846 1093586..1092741 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 SGDIDS000002723

IPK1 encodes an inositol 2-kinase that converts inositol 1,3,4,5,6-pentakisphosphate (IP5) to inositol 1,2,3,4,5,6-hexakisphosphate (IP6, also known as phytate) (2). Inositol polyphosphates, such as IP5 and IP6, are an important class of signaling molecules that regulate various processes such as transcription, DNA repair, chromatin remodeling, and telomere elongation (reviewed in 3). In particular, IP(6) and Ipk1p activity have been shown to be important for the process of mRNA export (1). Consistent with its role in mRNA export, Ipk1p localizes in the nucleus in a punctate pattern at the nuclear periphery (1). Null mutations in ipk1 result in temperature-sensitive growth, deficient in IP(6) production, accumulation of mRNA in the nucleus, and are lethal when combined a gle1 null mutation (4, 1).

Ipk1p activity is conserved from yeast to man and expression of the plant or human ortholog is able to complement the defects of an ipk1 null strain (4, 5). Knockouts of the mouse ortholog result in embryonic lethality and zebrafish knockdown experiments of 2-kinase activity result in developmental defects, implicating the importance of IP(6) in the development of higher organisms (reviewed in 3).

Last updated: 2008-01-22 Contact SGD

References cited on this page View Complete Literature Guide for IPK1
1) York JD, et al.  (1999) A phospholipase C-dependent inositol polyphosphate kinase pathway required for efficient messenger RNA export. Science 285(5424):96-100
2) Ives EB, et al.  (2000) Biochemical and functional characterization of inositol 1,3,4,5, 6-pentakisphosphate 2-kinases. J Biol Chem 275(47):36575-83
3) York JD  (2006) Regulation of nuclear processes by inositol polyphosphates. Biochim Biophys Acta 1761(5-6):552-9
4) Sweetman D, et al.  (2006) Characterization of an Arabidopsis inositol 1,3,4,5,6-pentakisphosphate 2-kinase (AtIPK1). Biochem J 394(Pt 1):95-103
5) Verbsky JW, et al.  (2002) The synthesis of inositol hexakisphosphate. Characterization of human inositol 1,3,4,5,6-pentakisphosphate 2-kinase. J Biol Chem 277(35):31857-62