Gene Symbol: GP ALPHA 1
Description: G protein alpha subunit 1
Alias: ARABIDOPSIS THALIANA G PROTEIN ALPHA SUBUNIT 1, ATGPA1, G PROTEIN ALPHA SUBUNIT, G PROTEIN ALPHA SUBUNIT 1, G protein alpha subunit 1, GPA1, T1D16.6, T1D16_6, G protein alpha subunit 1
Species: thale cress

Top Publications

  1. Weiss C, White E, Huang H, Ma H. The G protein alpha subunit (GP alpha1) is associated with the ER and the plasma membrane in meristematic cells of Arabidopsis and cauliflower. FEBS Lett. 1997;407:361-7 pubmed
  2. Chakravorty D, Botella J. Over-expression of a truncated Arabidopsis thaliana heterotrimeric G protein gamma subunit results in a phenotype similar to alpha and beta subunit knockouts. Gene. 2007;393:163-70 pubmed
  3. Zhang L, Hu G, Cheng Y, Huang J. Heterotrimeric G protein alpha and beta subunits antagonistically modulate stomatal density in Arabidopsis thaliana. Dev Biol. 2008;324:68-75 pubmed publisher
    ..The loss-of-function mutation of the G-protein alpha-subunit (GPA1) showed a reduction in stomatal density, while overexpression of the constitutively active form of GPA1(QL) ..
  4. Joo J, Wang S, Chen J, Jones A, Fedoroff N. Different signaling and cell death roles of heterotrimeric G protein alpha and beta subunits in the Arabidopsis oxidative stress response to ozone. Plant Cell. 2005;17:957-70 pubmed
  5. Ullah H, Chen J, Wang S, Jones A. Role of a heterotrimeric G protein in regulation of Arabidopsis seed germination. Plant Physiol. 2002;129:897-907 pubmed
    ..Seeds that carry a protein null mutation in the gene encoding the alpha subunit of the G protein in Arabidopsis (GPA1) are 100-fold less responsive to gibberellic acid (GA), have increased sensitivity to high levels of Glc, and have ..
  6. Johnston C, Taylor J, Gao Y, Kimple A, Grigston J, Chen J, et al. GTPase acceleration as the rate-limiting step in Arabidopsis G protein-coupled sugar signaling. Proc Natl Acad Sci U S A. 2007;104:17317-22 pubmed
    ..AtGPA1 is a unique heterotrimeric G protein alpha subunit that is constitutively GTP-bound given its high spontaneous nucleotide exchange coupled with slow GTP ..
  7. Okamoto H, Gobel C, Capper R, Saunders N, Feussner I, Knight M. The alpha-subunit of the heterotrimeric G-protein affects jasmonate responses in Arabidopsis thaliana. J Exp Bot. 2009;60:1991-2003 pubmed publisher
    ..a preliminary experiment was performed to assess the impact of the G alpha subunit loss-of-function mutation gpa1-1 on the Arabidopsis transcriptome...
  8. Coursol S, Fan L, Le Stunff H, Spiegel S, Gilroy S, Assmann S. Sphingolipid signalling in Arabidopsis guard cells involves heterotrimeric G proteins. Nature. 2003;423:651-4 pubmed
    ..wild-type plants, but not in knockout lines of the sole prototypical heterotrimeric G-protein alpha-subunit gene, GPA1 (refs 5, 6, 7-8)...
  9. Wang S, Assmann S, Fedoroff N. Characterization of the Arabidopsis heterotrimeric G protein. J Biol Chem. 2008;283:13913-22 pubmed publisher

More Information


  1. Chen J, Willard F, Huang J, Liang J, Chasse S, Jones A, et al. A seven-transmembrane RGS protein that modulates plant cell proliferation. Science. 2003;301:1728-31 pubmed
    ..These findings suggest that AtRGS1 is a critical modulator of plant cell proliferation. ..
  2. Pandey S, Assmann S. The Arabidopsis putative G protein-coupled receptor GCR1 interacts with the G protein alpha subunit GPA1 and regulates abscisic acid signaling. Plant Cell. 2004;16:1616-32 pubmed
    ..The Arabidopsis thaliana genome encodes single prototypical Galpha (GPA1) and Gbeta (AGB1) subunits, and two probable Ggamma subunits (AGG1 and AGG2)...
  3. Pandey S, Nelson D, Assmann S. Two novel GPCR-type G proteins are abscisic acid receptors in Arabidopsis. Cell. 2009;136:136-48 pubmed publisher
    ..proteins that show homology to an orphan vertebrate GPCR (GPR89) and interact with the sole Arabidopsis G protein alpha subunit, GPA1, but also have intrinsic GTP-binding and GTPase activity...
  4. Grigston J, Osuna D, Scheible W, Liu C, Stitt M, Jones A. D-Glucose sensing by a plasma membrane regulator of G signaling protein, AtRGS1. FEBS Lett. 2008;582:3577-84 pubmed publisher
    ..a receptor-like seven transmembrane domain with an RGS domain, interacts with the Arabidopsis Galpha subunit (AtGPA1) in a d-glucose-regulated manner, and stimulates AtGPA1 GTPase activity...
  5. Wang X, Ullah H, Jones A, Assmann S. G protein regulation of ion channels and abscisic acid signaling in Arabidopsis guard cells. Science. 2001;292:2070-2 pubmed
    ..DNA insertional mutations in the sole prototypical heterotrimeric GTP-binding (G) protein alpha subunit gene, GPA1, lack both ABA inhibition of guard cell inward K(+) channels and pH-independent ABA activation of anion channels...
  6. Fan L, Zhang W, Chen J, Taylor J, Jones A, Assmann S. Abscisic acid regulation of guard-cell K+ and anion channels in Gbeta- and RGS-deficient Arabidopsis lines. Proc Natl Acad Sci U S A. 2008;105:8476-81 pubmed publisher
    ..We evaluated plants harboring mutations in the sole Arabidopsis Galpha (AtGPA1), Gbeta (AGB1), and Regulator of G protein Signaling (AtRGS1) genes for impacts on ion channel regulation...
  7. Wang S, Narendra S, Fedoroff N. Heterotrimeric G protein signaling in the Arabidopsis unfolded protein response. Proc Natl Acad Sci U S A. 2007;104:3817-22 pubmed growth inhibition by the protein glycosylation inhibitor tunicamycin (Tm) than either wild-type plants or gpa1-4 (Galpha-null mutation) mutants...
  8. Zhang L, Wei Q, Wu W, Cheng Y, Hu G, Hu F, et al. Activation of the heterotrimeric G protein alpha-subunit GPA1 suppresses the ftsh-mediated inhibition of chloroplast development in Arabidopsis. Plant J. 2009;58:1041-53 pubmed publisher
    ..thylakoid formation 1 (thf1), indicating that inactivation or activation of the endogenous G protein alpha-subunit (GPA1) affects chloroplast development, as does the ectopic expression of the constitutively active Galpha-subunit (cGPA1)..
  9. Mishra G, Zhang W, Deng F, Zhao J, Wang X. A bifurcating pathway directs abscisic acid effects on stomatal closure and opening in Arabidopsis. Science. 2006;312:264-6 pubmed
    ..The results reveal a bifurcating signaling pathway that regulates plant water loss. ..
  10. Pandey S, Chen J, Jones A, Assmann S. G-protein complex mutants are hypersensitive to abscisic acid regulation of germination and postgermination development. Plant Physiol. 2006;141:243-56 pubmed
    ..To assess new roles for the Arabidopsis (Arabidopsis thaliana) Galpha subunit (GPA1), the Gbeta subunit (AGB1), and the candidate G-protein-coupled receptor (GCR1) in ABA signaling during germination ..
  11. Warpeha K, Lateef S, Lapik Y, Anderson M, Lee B, Kaufman L. G-protein-coupled receptor 1, G-protein Galpha-subunit 1, and prephenate dehydratase 1 are required for blue light-induced production of phenylalanine in etiolated Arabidopsis. Plant Physiol. 2006;140:844-55 pubmed
    ..protein (PD1) was discovered to have a strong interaction with the sole canonical G-protein Galpha-subunit (GPA1) in Arabidopsis (Arabidopsis thaliana)...
  12. Huang J, Taylor J, Chen J, Uhrig J, Schnell D, Nakagawa T, et al. The plastid protein THYLAKOID FORMATION1 and the plasma membrane G-protein GPA1 interact in a novel sugar-signaling mechanism in Arabidopsis. Plant Cell. 2006;18:1226-38 pubmed
    ..a Galpha interaction partner that functions downstream of the plasma membrane-delimited heterotrimeric G-protein (GPA1) in a D-glucose signaling pathway...
  13. Zhao J, Wang X. Arabidopsis phospholipase Dalpha1 interacts with the heterotrimeric G-protein alpha-subunit through a motif analogous to the DRY motif in G-protein-coupled receptors. J Biol Chem. 2004;279:1794-800 pubmed
  14. Willard F, Siderovski D. Purification and in vitro functional analysis of the Arabidopsis thaliana regulator of G-protein signaling-1. Methods Enzymol. 2004;389:320-38 pubmed
    ..thaliana contains a restricted set of heterotrimeric G-protein subunits, with only one canonical Galpha subunit (AtGPA1), one Gbeta subunit (AtAGB1), and two Ggamma subunits (AtAGG1 and AtGG2) identified...
  15. Wu Y, Xu X, Li S, Liu T, Ma L, Shang Z. Heterotrimeric G-protein participation in Arabidopsis pollen germination through modulation of a plasmamembrane hyperpolarization-activated Ca2+-permeable channel. New Phytol. 2007;176:550-9 pubmed
    ..with pollen grains of the wild type (ecotype Wassilewskija, ws), in vitro germinated pollen of Galpha null mutants (gpa1-1 and gpa1-2) had lower germination percentages and shorter pollen tubes, while pollen from Galpha overexpression ..
  16. Heo J, Sung S, Assmann S. Ca2+-dependent GTPase, extra-large G protein 2 (XLG2), promotes activation of DNA-binding protein related to vernalization 1 (RTV1), leading to activation of floral integrator genes and early flowering in Arabidopsis. J Biol Chem. 2012;287:8242-53 pubmed publisher
    ..In Arabidopsis, in addition to one prototypical G protein ? subunit, GPA1, there are three extra-large G proteins, XLG1, XLG2, and XLG3, of largely unknown function...
  17. Huang P, Yeh H, Yi H, Lin C, Yang C. Fluorescence-based assay probing regulator of G protein signaling partner proteins. Anal Biochem. 2012;423:133-40 pubmed publisher
    ..We validate the effectiveness of this method and suggest its application to the exploration of more RGS signaling partner proteins in physiological and pathological studies. ..
  18. Mason M, Botella J. Completing the heterotrimer: isolation and characterization of an Arabidopsis thaliana G protein gamma-subunit cDNA. Proc Natl Acad Sci U S A. 2000;97:14784-8 pubmed
    ..Also in agreement with previous observations, the removal of the N-terminal alpha-helix of the AGG1 greatly reduces but does not completely block the interaction. ..
  19. Chakraborty N, Sharma P, Kanyuka K, Pathak R, Choudhury D, Hooley R, et al. G-protein α-subunit (GPA1) regulates stress, nitrate and phosphate response, flavonoid biosynthesis, fruit/seed development and substantially shares GCR1 regulation in A. thaliana. Plant Mol Biol. 2015;89:559-76 pubmed publisher
    ..We isolated a knock-out mutant of the Arabidopsis G-protein α subunit (gpa1-5) and analysed its transcriptome to understand the genomewide role of GPA1 and compared it with that of our ..
  20. Ge X, Cai H, Lei X, Zhou X, Yue M, He J. Heterotrimeric G protein mediates ethylene-induced stomatal closure via hydrogen peroxide synthesis in Arabidopsis. Plant J. 2015;82:138-50 pubmed publisher
    ..Here, evidences are provided to show the Gα subunit GPA1 as a missing link between ethylene and H2O2 in guard cell ethylene signalling...
  21. Booker K, Schwarz J, Garrett M, Jones A. Glucose attenuation of auxin-mediated bimodality in lateral root formation is partly coupled by the heterotrimeric G protein complex. PLoS ONE. 2010;5: pubmed publisher
    ..The heterotrimeric G protein complex in Arabidopsis thaliana, defined as containing alpha (AtGPA1), beta (AGB1), and gamma (AGG) subunits and a GTPase accelerating protein called Regulator of G Signaling 1 ..
  22. Gao Y, Wang S, Asami T, Chen J. Loss-of-function mutations in the Arabidopsis heterotrimeric G-protein alpha subunit enhance the developmental defects of brassinosteroid signaling and biosynthesis mutants. Plant Cell Physiol. 2008;49:1013-24 pubmed publisher
    Loss-of-function alleles of the sole heterotrimeric G-protein alpha subunit in Arabidopsis, GPA1, display defects in cell proliferation throughout plant development...
  23. Gookin T, Assmann S. Significant reduction of BiFC non-specific assembly facilitates in planta assessment of heterotrimeric G-protein interactors. Plant J. 2014;80:553-67 pubmed publisher
    ..MLO1 interacting with a calmodulin-like (CML) protein, and by showing that heterotrimeric G-protein subunits Gα (GPA1) and Gβ (AGB1) interact in plant cells...
  24. Liu X, Yue Y, Li B, Nie Y, Li W, Wu W, et al. A G protein-coupled receptor is a plasma membrane receptor for the plant hormone abscisic acid. Science. 2007;315:1712-6 pubmed
    ..Here, we report that a G protein-coupled receptor genetically and physically interacts with the G protein alpha subunit GPA1 to mediate all known ABA responses in Arabidopsis...
  25. Li S, Liu Y, Zheng L, Chen L, Li N, Corke F, et al. The plant-specific G protein ? subunit AGG3 influences organ size and shape in Arabidopsis thaliana. New Phytol. 2012;194:690-703 pubmed publisher
    ..Genetic analyses revealed that AGG3 action requires a functional G protein ? subunit (GPA1) and G protein ? subunit (AGB1)...
  26. Jones J, Duffy J, Machius M, Temple B, Dohlman H, Jones A. The crystal structure of a self-activating G protein alpha subunit reveals its distinct mechanism of signal initiation. Sci Signal. 2011;4:ra8 pubmed publisher
    ..G protein ? subunits; however, the plant Arabidopsis thaliana lacks canonical GPCRs, and its G protein ? subunit (AtGPA1) is self-activating. To investigate how AtGPA1 becomes activated, we determined its crystal structure...
  27. Zhang W, Jeon B, Assmann S. Heterotrimeric G-protein regulation of ROS signalling and calcium currents in Arabidopsis guard cells. J Exp Bot. 2011;62:2371-9 pubmed publisher
    ..Previous analyses of mutants deficient in the sole canonical Arabidopsis G? subunit, GPA1, have shown that G?-deficient guard cells are impaired in ABA inhibition of K(+) influx channels, and in pH-..
  28. Shen Y, Han Y, Kim J, Song P. Arabidopsis nucleoside diphosphate kinase-2 as a plant GTPase activating protein. BMB Rep. 2008;41:645-50 pubmed
    ..relationship between NDPK2 and the small G proteins, Pra2 and Pra3, as well as the heterotrimeric G protein, GPA1. We report a physical interaction between NDPK2 and these small G proteins, and demonstrate that NDPK2 can ..
  29. Aranda Sicilia M, Trusov Y, Maruta N, Chakravorty D, Zhang Y, Botella J. Heterotrimeric G proteins interact with defense-related receptor-like kinases in Arabidopsis. J Plant Physiol. 2015;188:44-8 pubmed publisher
    ..At the same time, no interaction was detected with the non-RD RLK FLS2. We hypothesize that G-proteins mediate signal transduction immediately downstream of the pathogenesis-related RLKs. ..
  30. Lapik Y, Kaufman L. The Arabidopsis cupin domain protein AtPirin1 interacts with the G protein alpha-subunit GPA1 and regulates seed germination and early seedling development. Plant Cell. 2003;15:1578-90 pubmed
    ..two-hybrid screen was performed to search for proteins that interact with Arabidopsis G protein alpha-subunit (GPA1). One of the identified GPA1-interacting proteins is the cupin-domain protein AtPirin1...
  31. Pandey S, Wang R, Wilson L, Li S, Zhao Z, Gookin T, et al. Boolean modeling of transcriptome data reveals novel modes of heterotrimeric G-protein action. Mol Syst Biol. 2010;6:372 pubmed publisher
    ..Our method holds significant promise for analyzing analogous 'switch-like' signal transduction events in any organism...
  32. Li J, Liu Y, Lu P, Lin H, Bai Y, Wang X, et al. A signaling pathway linking nitric oxide production to heterotrimeric G protein and hydrogen peroxide regulates extracellular calmodulin induction of stomatal closure in Arabidopsis. Plant Physiol. 2009;150:114-24 pubmed publisher
    ..Furthermore, we found that ExtCaM-mediated NO generation is regulated by GPA1, the Galpha-subunit of heterotrimeric G protein...
  33. He J, Ma X, Zhang Y, Sun T, Xu F, Chen Y, et al. Role and interrelationship of G? protein, hydrogen peroxide, and nitric oxide in ultraviolet B-induced stomatal closure in Arabidopsis leaves. Plant Physiol. 2013;161:1570-83 pubmed publisher
    ..Furthermore, we found that UV-B-mediated H2O2 and NO generation are regulated by GPA1, the G?-subunit of heterotrimeric G proteins...
  34. Fox A, Soto G, Jones A, Casal J, Muschietti J, Mazzella M. cry1 and GPA1 signaling genetically interact in hook opening and anthocyanin synthesis in Arabidopsis. Plant Mol Biol. 2012;80:315-24 pubmed publisher complete darkness, a phenotype that resembles the one described for the heterotrimeric G-protein ? subunit (GPA1) null mutant gpa1. Both cry1 and gpa1 also showed reduced accumulation of anthocyanin under blue light...
  35. Warpeha K, Upadhyay S, Yeh J, Adamiak J, Hawkins S, Lapik Y, et al. The GCR1, GPA1, PRN1, NF-Y signal chain mediates both blue light and abscisic acid responses in Arabidopsis. Plant Physiol. 2007;143:1590-600 pubmed
    ..The chain consists of GCR1 (the sole Arabidopsis protein coding for a potential G-protein-coupled receptor), GPA1 (the sole Arabidopsis Galpha-subunit), Pirin1 (PRN1; one of four members of an iron-containing subgroup of the ..
  36. Adjobo Hermans M, Goedhart J, Gadella T. Plant G protein heterotrimers require dual lipidation motifs of Galpha and Ggamma and do not dissociate upon activation. J Cell Sci. 2006;119:5087-97 pubmed
    ..Importantly, rendering GPalpha1 constitutively active did not cause a FRET decrease in the heterotrimer, suggesting no dissociation upon GPalpha1 activation. ..
  37. Chen Y, Huang R, Xiao Y, Lu P, Chen J, Wang X. Extracellular calmodulin-induced stomatal closure is mediated by heterotrimeric G protein and H2O2. Plant Physiol. 2004;136:4096-103 pubmed stomatal closure, we checked guard cell responses in the Arabidopsis (Arabidopsis thaliana) Galpha-subunit-null gpa1 mutants and cGalpha overexpression lines...
  38. Liu F, Bian Z, Jia Z, Zhao Q, Song S. The GCR1 and GPA1 participate in promotion of Arabidopsis primary root elongation induced by N-acyl-homoserine lactones, the bacterial quorum-sensing signals. Mol Plant Microbe Interact. 2012;25:677-83 pubmed publisher
    ..The loss-of-function mutants of the sole canonical G? subunit GPA1 showed no response to AHL promotion of root elongation whereas G? gain-of-function plants overexpressing either the ..