IPT1/YDR072C Summary Help

Standard Name IPT1 1
Systematic Name YDR072C
Alias SYR4 , KTI6 2
Feature Type ORF, Verified
Description Inositolphosphotransferase, involved in synthesis of mannose-(inositol-P)2-ceramide (M(IP)2C), the most abundant sphingolipid; can mutate to resistance to the antifungals syringomycin E and DmAMP1 and to K. lactis zymocin (3, 4, 5, 6 and see Summary Paragraph)
Name Description InositolPhosphoTransferase 3
Chromosomal Location
ChrIV:591344 to 589761 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gbrowse
Gene Ontology Annotations All IPT1 GO evidence and references
  View Computational GO annotations for IPT1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
High-throughput
Pathways
Mutant phenotypes All IPT1 Phenotype evidence and references
Classical genetics
null
unspecified
Large-scale survey
null
overexpression
Resources
interactions All IPT1 Interaction evidence and references
113 total interaction(s) for 88 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 1
  • Affinity Capture-RNA: 2
  • Biochemical Activity: 1
  • PCA: 1
  • Protein-RNA: 1
Genetic Interactions
  • Dosage Rescue: 2
  • Negative Genetic: 65
  • Phenotypic Enhancement: 3
  • Phenotypic Suppression: 1
  • Positive Genetic: 29
  • Synthetic Growth Defect: 2
  • Synthetic Lethality: 1
  • Synthetic Rescue: 4
Resources
Expression Summary
histogram
Resources
Protein Information All IPT1 Protein evidence and references
Localization
Phosphorylation PhosphoGRID | PhosphoPep Database
Structure
Homologs
sequence information
ChrIV:591344 to 589761 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
SGD ORF map
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Relative
Coordinates		 Chromosomal
Coordinates		 Most Recent Updates
Coordinates Sequence
CDS 1..1584 591344..589761 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
Resources
External Links All Associated Seq | E.C. | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000002479
SUMMARY PARAGRAPH for IPT1

About sphingolipid metabolism

Sphingolipids are essential components of the plasma membrane in all eukaryotic cells. S. cerevisiae cells make three complex sphingolipids: inositol-phosphoceramide (IPC), mannose-inositol-phosphoceramide (MIPC), and mannose-(inositol phosphate)2-ceramide (M(IP)2C)(7). In the yeast plasma membrane sphingolipids concentrate with ergosterol to form lipid rafts, specialized membrane microdomains implicated in a variety of cellular processes, including sorting of membrane proteins and lipids, as well as organizing and regulating signaling cascades (8). Intermediates in sphingolipid biosynthesis have been shown to play important roles as signaling molecules and growth regulators. Sphingolipid long chain bases (LCBs), dihydrosphingosine (DHS) and phytosphingosine (PHS), have been implicated as secondary messengers in signaling pathways that regulate the heat stress response (9, 10). Other intermediates, phytoceramide and long-chain base phosphates (LCBPs), have been shown to be components of the tightly-controlled ceramide/LCBP rheostat, which regulates cell growth (11). Since phosphoinositol-containing sphingolipids are unique to fungi, the sphingolipid biosynthesis pathway is considered a target for antifungal drugs (12, 13).

Last updated: 2007-10-05

References cited on this page View Complete Literature Guide for IPT1
1) Stock SD, et al.  (1999) SEC14-dependent secretion in Saccharomyces cerevisiae. Nondependence on sphingolipid synthesis-coupled diacylglycerol production. J Biol Chem 274(19):12979-83
2) Butler AR, et al.  (1994) Two Saccharomyces cerevisiae genes which control sensitivity to G1 arrest induced by Kluyveromyces lactis toxin. Mol Cell Biol 14(9):6306-16
3) Dickson RC, et al.  (1997) Synthesis of mannose-(inositol-P)2-ceramide, the major sphingolipid in Saccharomyces cerevisiae, requires the IPT1 (YDR072c) gene. J Biol Chem 272(47):29620-5
4) Stock SD, et al.  (2000) Syringomycin E inhibition of Saccharomyces cerevisiae: requirement for biosynthesis of sphingolipids with very-long-chain fatty acids and mannose- and phosphoinositol-containing head groups. Antimicrob Agents Chemother 44(5):1174-80
5) Thevissen K, et al.  (2000) A gene encoding a sphingolipid biosynthesis enzyme determines the sensitivity of Saccharomyces cerevisiae to an antifungal plant defensin from dahlia (Dahlia merckii). Proc Natl Acad Sci U S A 97(17):9531-6
6) Zink S, et al.  (2005) Mannosyl-diinositolphospho-ceramide, the major yeast plasma membrane sphingolipid, governs toxicity of Kluyveromyces lactis zymocin. Eukaryot Cell 4(5):879-89
7) Dickson RC and Lester RL  (2002) Sphingolipid functions in Saccharomyces cerevisiae. Biochim Biophys Acta 1583(1):13-25
8) Bagnat M and Simons K  (2002) Lipid rafts in protein sorting and cell polarity in budding yeast Saccharomyces cerevisiae. Biol Chem 383(10):1475-80
9) Jenkins GM, et al.  (1997) Involvement of yeast sphingolipids in the heat stress response of Saccharomyces cerevisiae. J Biol Chem 272(51):32566-72
10) Ferguson-Yankey SR, et al.  (2002) Mutant analysis reveals complex regulation of sphingolipid long chain base phosphates and long chain bases during heat stress in yeast. Yeast 19(7):573-86
11) Kobayashi SD and Nagiec MM  (2003) Ceramide/long-chain base phosphate rheostat in Saccharomyces cerevisiae: regulation of ceramide synthesis by Elo3p and Cka2p. Eukaryot Cell 2(2):284-94
12) Nagiec MM, et al.  (1997) Sphingolipid synthesis as a target for antifungal drugs. Complementation of the inositol phosphorylceramide synthase defect in a mutant strain of Saccharomyces cerevisiae by the AUR1 gene. J Biol Chem 272(15):9809-17
13) Sugimoto Y, et al.  (2004) IPC synthase as a useful target for antifungal drugs. Curr Drug Targets Infect Disord 4(4):311-22