Gene Symbol: IRA1
Description: GTPase-activating protein IRA1
Alias: GLC1, PPD1, GTPase-activating protein IRA1
Species: Saccharomyces cerevisiae S288c

Top Publications

  1. Colombo S, Ma P, Cauwenberg L, Winderickx J, Crauwels M, Teunissen A, et al. Involvement of distinct G-proteins, Gpa2 and Ras, in glucose- and intracellular acidification-induced cAMP signalling in the yeast Saccharomyces cerevisiae. EMBO J. 1998;17:3326-41 pubmed
    ..Deletion of the GTPase-activating proteins Ira1 and Ira2, or expression of the RAS2(val19) allele, causes an enhanced GTP/GDP basal ratio and abolishes the ..
  2. Chen R, Michaeli T, Van Aelst L, Ballester R. A role for the noncatalytic N terminus in the function of Cdc25, a Saccharomyces cerevisiae Ras-guanine nucleotide exchange factor. Genetics. 2000;154:1473-84 pubmed
    ..Taken together these results suggest that the N terminus plays a crucial role in regulating Cdc25 and consequently Ras activity, which in S. cerevisiae is essential for cell cycle progression. ..
  3. Luo G, Kim J, Song K. The C-terminal domains of human neurofibromin and its budding yeast homologs Ira1 and Ira2 regulate the metaphase to anaphase transition. Cell Cycle. 2014;13:2780-9 pubmed publisher
    ..yeast Saccharomyces cerevisiae is a good model system for studying neurofibromin function because it possesses Ira1 and Ira2, which are homologous to human neurofibromin in both sequence and function...
  4. Casado C, González A, Platara M, Ruiz A, Arino J. The role of the protein kinase A pathway in the response to alkaline pH stress in yeast. Biochem J. 2011;438:523-33 pubmed publisher
    ..Phenotypic analysis revealed that mutations that activate the PKA pathway (ira1 ira2, bcy1) tend to cause sensitivity to alkaline pH, whereas its deactivation enhances tolerance to this stress...
  5. Wood M, Sanchez Y. Deregulated Ras signaling compromises DNA damage checkpoint recovery in S. cerevisiae. Cell Cycle. 2010;9:3353-63 pubmed publisher
    ..Here we report that in budding yeast, deletion of the IRA1 and IRA2 genes encoding negative regulators of Ras prevents cellular recovery from a DNA damage induced arrest...
  6. Bishop A, Surlow B, Anand P, Hofer K, Henkel M, Patton Vogt J. Neurofibromin homologs Ira1 and Ira2 affect glycerophosphoinositol production and transport in Saccharomyces cerevisiae. Eukaryot Cell. 2009;8:1808-11 pubmed publisher
    ..A screening identified the RAS GTPase-activating proteins Ira1 and Ira2 as required for utilization of glycerophosphoinositol as the sole phosphate source, but the RAS/cyclic AMP ..
  7. Ruggieri R, Bender A, Matsui Y, Powers S, Takai Y, Pringle J, et al. RSR1, a ras-like gene homologous to Krev-1 (smg21A/rap1A): role in the development of cell polarity and interactions with the Ras pathway in Saccharomyces cerevisiae. Mol Cell Biol. 1992;12:758-66 pubmed
    ..This interaction of Rsr1p with the effector of Ras in S. cerevisiae suggests that Krev-1 may revert ras-induced transformation of mammalian cells by affecting the interaction of ras p21 with its effector. ..
  8. Rupp S, Summers E, Lo H, Madhani H, Fink G. MAP kinase and cAMP filamentation signaling pathways converge on the unusually large promoter of the yeast FLO11 gene. EMBO J. 1999;18:1257-69 pubmed
    ..Thus, like the promoters of the key developmental genes, HO and IME1, the FLO11 promoter is large and complex, endowing it with the ability to integrate multiple inputs. ..
  9. Wood D, Poullet P, Wilson B, Khalil M, Tanaka K, Cannon J, et al. Biochemical characterization of yeast RAS2 mutants reveals a new region of ras protein involved in the interaction with GTPase-activating proteins. J Biol Chem. 1994;269:5322-7 pubmed
    ..These results suggest that the interaction between ras and GAP involves a larger region within ras than previously recognized. ..

More Information


  1. Shirayama M, Matsui Y, Tanaka K, Toh e A. Isolation of a CDC25 family gene, MSI2/LTE1, as a multicopy suppressor of ira1. Yeast. 1994;10:451-61 pubmed
    ..cerevisiae which, when on a multicopy vector, suppresses the heat shock sensitivity caused by the loss of the IRA1 product, a negative regulator of the RAS protein...
  2. Ruggieri R, Tanaka K, Nakafuku M, Kaziro Y, Toh e A, Matsumoto K. MSI1, a negative regulator of the RAS-cAMP pathway in Saccharomyces cerevisiae. Proc Natl Acad Sci U S A. 1989;86:8778-82 pubmed
    We have previously demonstrated that the IRA1-encoded protein inhibits the function of the RAS protein in a fashion antagonistic to the function of the CDC25 protein in the RAS-cAMP pathway in Saccharomyces cerevisiae...
  3. Colombo S, Ronchetti D, Thevelein J, Winderickx J, Martegani E. Activation state of the Ras2 protein and glucose-induced signaling in Saccharomyces cerevisiae. J Biol Chem. 2004;279:46715-22 pubmed
    ..Deletion of the Ras-GAPs IRA2 (alone or with IRA1) or the presence of RAS2Val19 allele causes constitutively high Ras GTP loading that no longer increases upon ..
  4. Trott A, Shaner L, Morano K. The molecular chaperone Sse1 and the growth control protein kinase Sch9 collaborate to regulate protein kinase A activity in Saccharomyces cerevisiae. Genetics. 2005;170:1009-21 pubmed
    ..Together these results demonstrate that the Sse1 chaperone and the growth control kinase Sch9 independently contribute to regulation of PKA signaling. ..
  5. Harashima T, Anderson S, Yates J, Heitman J. The kelch proteins Gpb1 and Gpb2 inhibit Ras activity via association with the yeast RasGAP neurofibromin homologs Ira1 and Ira2. Mol Cell. 2006;22:819-30 pubmed
    ..Here, we define these targets of Gpb1/2 as the yeast neurofibromin homologs Ira1 and Ira2, which function as GTPase activating proteins of Ras...
  6. Tanaka K, Nakafuku M, Tamanoi F, Kaziro Y, Matsumoto K, Toh e A. IRA2, a second gene of Saccharomyces cerevisiae that encodes a protein with a domain homologous to mammalian ras GTPase-activating protein. Mol Cell Biol. 1990;10:4303-13 pubmed
    The IRA1 gene is a negative regulator of the RAS-cyclic AMP pathway in Saccharomyces cerevisiae...
  7. Mitts M, Bradshaw Rouse J, Heideman W. Interactions between adenylate cyclase and the yeast GTPase-activating protein IRA1. Mol Cell Biol. 1991;11:4591-8 pubmed
    ..mediate stimulation of cyclic AMP synthesis by guanine nucleotides, and the yeast GTPase-activating protein analog IRA1. We have previously reported that adenylate cyclase is only peripherally bound to the yeast membrane...
  8. Sobering A, Jung U, Lee K, Levin D. Yeast Rpi1 is a putative transcriptional regulator that contributes to preparation for stationary phase. Eukaryot Cell. 2002;1:56-65 pubmed
    ..Finally, we propose that inappropriate expression of RPI1 during log phase growth drives fortification of the cell wall and that this behavior is responsible for suppression of the mpkl cell lysis defect. ..
  9. Phan V, Ding V, Li F, Chalkley R, Burlingame A, McCormick F. The RasGAP proteins Ira2 and neurofibromin are negatively regulated by Gpb1 in yeast and ETEA in humans. Mol Cell Biol. 2010;30:2264-79 pubmed publisher
    ..The yeast Saccharomyces cerevisiae has two neurofibromin homologs, Ira1 and Ira2...
  10. Tanaka K, Nakafuku M, Satoh T, Marshall M, Gibbs J, Matsumoto K, et al. S. cerevisiae genes IRA1 and IRA2 encode proteins that may be functionally equivalent to mammalian ras GTPase activating protein. Cell. 1990;60:803-7 pubmed
    The IRA1 and IRA2 genes of S. cerevisiae encode closely related proteins that also share homology with mammalian GAP (ras GTPase activating protein)...
  11. Ruiz A, Xu X, Carlson M. Roles of two protein phosphatases, Reg1-Glc7 and Sit4, and glycogen synthesis in regulation of SNF1 protein kinase. Proc Natl Acad Sci U S A. 2011;108:6349-54 pubmed publisher
    ..Finally, evidence that the effects of glycogen are not mediated by binding to the ?-subunit raises the possibility that elevated glycogen synthesis alters glucose metabolism and thereby reduces glucose signaling to the SNF1 pathway. ..
  12. Barrett L, Orlova M, Maziarz M, Kuchin S. Protein kinase A contributes to the negative control of Snf1 protein kinase in Saccharomyces cerevisiae. Eukaryot Cell. 2012;11:119-28 pubmed publisher
    ..the mutants in the ?1278b strains employed here helped us identify fst1 and fst2 as mutations in the RasGAP genes IRA1 and IRA2...
  13. Fujimura K, Tanaka K, Nakano A, Toh e A. The Saccharomyces cerevisiae MSI4 gene encodes the yeast counterpart of component A of Rab geranylgeranyltransferase. J Biol Chem. 1994;269:9205-12 pubmed
    We describe the isolation of MSI4 as a multicopy suppressor of ira1 (inhibitory regulator of Ras)...
  14. Shirayama M, Kawakami K, Matsui Y, Tanaka K, Toh e A. MSI3, a multicopy suppressor of mutants hyperactivated in the RAS-cAMP pathway, encodes a novel HSP70 protein of Saccharomyces cerevisiae. Mol Gen Genet. 1993;240:323-32 pubmed
    The MSI3 gene was isolated as a multicopy suppressor of the heat shock-sensitive phenotype of the ira1 mutation, which causes hyperactivation of the RAS-cAMP pathway...
  15. Tanaka K, Matsumoto K, Toh e A. IRA1, an inhibitory regulator of the RAS-cyclic AMP pathway in Saccharomyces cerevisiae. Mol Cell Biol. 1989;9:757-68 pubmed
    A mutation in the gene IRA1 (formerly called PPD1) was originally characterized as a deficiency of a phosphoprotein phosphatase. The IRA1 gene has been cloned and sequenced...