Gene Symbol: IAA7
Description: indole-3-acetic acid 7
Alias: AUXIN RESISTANT 2, AXR2, indole-3-acetic acid 7, indole-3-acetic acid 7
Species: thale cress
Products:     IAA7

Top Publications

  1. Tan X, Calderon Villalobos L, Sharon M, Zheng C, Robinson C, Estelle M, et al. Mechanism of auxin perception by the TIR1 ubiquitin ligase. Nature. 2007;446:640-5 pubmed
    ..By filling in a hydrophobic cavity at the protein interface, auxin enhances the TIR1-substrate interactions by acting as a 'molecular glue'. Our results establish the first structural model of a plant hormone receptor. ..
  2. Dharmasiri N, Dharmasiri S, Jones A, Estelle M. Auxin action in a cell-free system. Curr Biol. 2003;13:1418-22 pubmed
    ..In addition, we show that the response is not dependent on protein phosphorylation or dephosphorylation but rather is prevented by an inhibitor of peptidyl-prolyl isomerases. ..
  3. Kepinski S, Leyser O. The Arabidopsis F-box protein TIR1 is an auxin receptor. Nature. 2005;435:446-51 pubmed
    ..Here we show that this modification involves the direct binding of auxin to TIR1 and thus that TIR1 is an auxin receptor mediating transcriptional responses to auxin. ..
  4. Dharmasiri N, Dharmasiri S, Weijers D, Lechner E, Yamada M, Hobbie L, et al. Plant development is regulated by a family of auxin receptor F box proteins. Dev Cell. 2005;9:109-19 pubmed
    ..Correspondingly, all TIR1/AFB proteins interact with BDL, and BDL is stabilized in triple mutant plants. Our results indicate that TIR1 and the AFB proteins collectively mediate auxin responses throughout plant development. ..
  5. Gray W, Kepinski S, Rouse D, Leyser O, Estelle M. Auxin regulates SCF(TIR1)-dependent degradation of AUX/IAA proteins. Nature. 2001;414:271-6 pubmed
    ..Here we show that SCF(TIR1) is required for AUX/IAA degradation. We demonstrate that SCF(TIR1) interacts with AXR2/IAA7 and AXR3/IAA17, and that domain II of these proteins is necessary and sufficient for this interaction...
  6. Muto H, Watahiki M, Nakamoto D, Kinjo M, Yamamoto K. Specificity and similarity of functions of the Aux/IAA genes in auxin signaling of Arabidopsis revealed by promoter-exchange experiments among MSG2/IAA19, AXR2/IAA7, and SLR/IAA14. Plant Physiol. 2007;144:187-96 pubmed
    ..examined phenotypes of transgenic plants expressing the green fluorescent protein (GFP)-tagged msg2-1/iaa19, axr2-1/iaa7, or slr-1/iaa14 cDNA by the MSG2 or AXR2 promoter...
  7. Hu Y, Yang L, Na X, You J, Hu W, Liang X, et al. Narciclasine inhibits the responses of Arabidopsis roots to auxin. Planta. 2012;236:597-612 pubmed publisher
    ..In addition, NCS did not alter the auxin-stimulated interaction between IAA7/AXR2 (Aux/IAA proteins) and the F-box protein TIR1 activity of the proteasome...
  8. Terrile M, París R, Calderon Villalobos L, Iglesias M, Lamattina L, Estelle M, et al. Nitric oxide influences auxin signaling through S-nitrosylation of the Arabidopsis TRANSPORT INHIBITOR RESPONSE 1 auxin receptor. Plant J. 2012;70:492-500 pubmed publisher
    ..Our findings underline the importance of NO in phytohormone signaling pathways. ..
  9. Dharmasiri N, Dharmasiri S, Estelle M. The F-box protein TIR1 is an auxin receptor. Nature. 2005;435:441-5 pubmed
    ..Finally, TIR1 synthesized in insect cells binds Aux/IAA proteins in an auxin-dependent manner. Together, these results indicate that TIR1 is an auxin receptor that mediates Aux/IAA degradation and auxin-regulated transcription. ..

More Information


  1. Parry G, Calderon Villalobos L, Prigge M, Peret B, Dharmasiri S, Itoh H, et al. Complex regulation of the TIR1/AFB family of auxin receptors. Proc Natl Acad Sci U S A. 2009;106:22540-5 pubmed publisher
    ..However our data suggest that this regulation is complex. Our results suggest that differences between members of the auxin receptor family may contribute to the complexity of auxin response. ..
  2. Sungur C, Miller S, Bergholz J, Hoye R, Brisbois R, Overvoorde P. The small molecule 2-furylacrylic acid inhibits auxin-mediated responses in Arabidopsis thaliana. Plant Cell Physiol. 2007;48:1693-701 pubmed
    ..In the micromolar range, 2-FAA attenuates the auxin-inducible expression of IAA5, fails to alter the interaction of IAA7/AXR2 with the SCF(TIR1) complex and inhibits both root and hypocotyl elongation of wild-type seedlings...
  3. Nan W, Wang X, Yang L, Hu Y, Wei Y, Liang X, et al. Cyclic GMP is involved in auxin signalling during Arabidopsis root growth and development. J Exp Bot. 2014;65:1571-83 pubmed publisher
    ..Our results suggest that cGMP acts as a mediator to participate in auxin signalling and may govern this process by PKG activity via its in?uence on auxin-regulated gene expression and auxin/IAA degradation. ..
  4. Hellmann H, Hobbie L, Chapman A, Dharmasiri S, Dharmasiri N, Del Pozo C, et al. Arabidopsis AXR6 encodes CUL1 implicating SCF E3 ligases in auxin regulation of embryogenesis. EMBO J. 2003;22:3314-25 pubmed
    ..of mutant CUL1 to assemble into stable SCF complexes resulting in reduced degradation of the SCF(TIR1) substrate AXR2/IAA7...
  5. Wilson A, Pickett F, Turner J, Estelle M. A dominant mutation in Arabidopsis confers resistance to auxin, ethylene and abscisic acid. Mol Gen Genet. 1990;222:377-83 pubmed
    ..One of the resistant lines identified in this screen carries a dominant mutation which we have named axr2. Linkage analysis indicates that the axr2 gene lies on chromosome 3...
  6. Mai Y, Wang L, Yang H. A gain-of-function mutation in IAA7/AXR2 confers late flowering under short-day light in Arabidopsis. J Integr Plant Biol. 2011;53:480-92 pubmed publisher
    ..We have defined the role of the auxin signaling component INDOLE-3-ACETIC ACID 7 (IAA7)/AUXIN RESISTANT 2 (AXR2) in the regulation of flowering time in Arabidopsis thaliana...
  7. Arase F, Nishitani H, Egusa M, Nishimoto N, Sakurai S, Sakamoto N, et al. IAA8 involved in lateral root formation interacts with the TIR1 auxin receptor and ARF transcription factors in Arabidopsis. PLoS ONE. 2012;7:e43414 pubmed publisher
    ..Taken together, our results show that IAA8 is involved in lateral root formation, and that this process is regulated through the interaction with the TIR1 auxin receptor and ARF transcription factors in the nucleus. ..
  8. Leymarie J, Damerval C, Marcotte L, Combes V, Vartanian N. Two-dimensional protein patterns of Arabidopsis wild-type and auxin insensitive mutants, axr1, axr2, reveal interactions between drought and hormonal responses. Plant Cell Physiol. 1996;37:966-75 pubmed
    ..involved in Arabidopsis drought adaptive strategy, 2D-PAGE protein patterns of two auxin-insensitive mutants, axr1, axr2, differentially affected in specific drought responses, were compared to the wild-type Columbia ecotype, in well-..
  9. Devoto A, Ellis C, Magusin A, Chang H, Chilcott C, Zhu T, et al. Expression profiling reveals COI1 to be a key regulator of genes involved in wound- and methyl jasmonate-induced secondary metabolism, defence, and hormone interactions. Plant Mol Biol. 2005;58:497-513 pubmed
    ..These results indicate that COI1 plays a pivotal role in wound- and JA signalling. ..
  10. Belin C, Megies C, Hauserová E, Lopez Molina L. Abscisic acid represses growth of the Arabidopsis embryonic axis after germination by enhancing auxin signaling. Plant Cell. 2009;21:2253-68 pubmed publisher
    ..This involves repression of the AUXIN INDUCIBLE (Aux/IAA) gene AXR2/IAA7, encoding a key component of ABA- and auxin-dependent responses during postgerminative growth.
  11. Liscum E, Reed J. Genetics of Aux/IAA and ARF action in plant growth and development. Plant Mol Biol. 2002;49:387-400 pubmed
    ..We will also discuss potential mechanisms for interactions between auxin and light response pathways that are suggested by these mutants. ..
  12. Hayashi K, Neve J, Hirose M, Kuboki A, Shimada Y, Kepinski S, et al. Rational design of an auxin antagonist of the SCF(TIR1) auxin receptor complex. ACS Chem Biol. 2012;7:590-8 pubmed publisher
  13. Chuang H, Zhang W, Gray W. Arabidopsis ETA2, an apparent ortholog of the human cullin-interacting protein CAND1, is required for auxin responses mediated by the SCF(TIR1) ubiquitin ligase. Plant Cell. 2004;16:1883-97 pubmed
    ..Our genetic and molecular analysis of SCF(TIR1) function in eta2 mutants provides novel insight into the role of CAND1 in the regulation of SCF ubiquitin-ligase activity. ..
  14. Gilkerson J, Kelley D, Tam R, Estelle M, Callis J. Lysine Residues Are Not Required for Proteasome-Mediated Proteolysis of the Auxin/Indole Acidic Acid Protein IAA1. Plant Physiol. 2015;168:708-20 pubmed publisher
    ..versions of IAA1 localized to the nucleus as Yellow Fluorescent Protein fusions and interacted with both TIR1 and IAA7 in yeast (Saccharomyces cerevisiae) two-hybrid experiments, indicating that these proteins were functional...
  15. Cui F, Wu S, Sun W, Coaker G, KUNKEL B, He P, et al. The Pseudomonas syringae type III effector AvrRpt2 promotes pathogen virulence via stimulating Arabidopsis auxin/indole acetic acid protein turnover. Plant Physiol. 2013;162:1018-29 pubmed publisher
    ..Importantly, transgenic plants expressing the dominant axr2-1 mutation recalcitrant to AvrRpt2-mediated degradation ameliorated the virulence functions of AvrRpt2 but did not ..
  16. Sato A, Sasaki S, Matsuzaki J, Yamamoto K. Light-dependent gravitropism and negative phototropism of inflorescence stems in a dominant Aux/IAA mutant of Arabidopsis thaliana, axr2. J Plant Res. 2014;127:627-39 pubmed publisher
    ..and phototropism of the primary inflorescence stems were examined in a dominant Aux/IAA mutant of Arabidopsis, axr2/iaa7, which did not display either tropism in hypocotyls...
  17. Calderon Villalobos L, Lee S, de Oliveira C, Ivetac A, Brandt W, Armitage L, et al. A combinatorial TIR1/AFB-Aux/IAA co-receptor system for differential sensing of auxin. Nat Chem Biol. 2012;8:477-85 pubmed publisher
    ..This co-receptor system broadens the effective concentration range of the hormone and may contribute to the complexity of auxin response. ..
  18. Tao L, Cheung A, Nibau C, Wu H. RAC GTPases in tobacco and Arabidopsis mediate auxin-induced formation of proteolytically active nuclear protein bodies that contain AUX/IAA proteins. Plant Cell. 2005;17:2369-83 pubmed
  19. Katz E, Nisani S, Yadav B, Woldemariam M, Shai B, Obolski U, et al. The glucosinolate breakdown product indole-3-carbinol acts as an auxin antagonist in roots of Arabidopsis thaliana. Plant J. 2015;82:547-55 pubmed publisher
  20. Zhang W, Ito H, Quint M, Huang H, Noël L, Gray W. Genetic analysis of CAND1-CUL1 interactions in Arabidopsis supports a role for CAND1-mediated cycling of the SCFTIR1 complex. Proc Natl Acad Sci U S A. 2008;105:8470-5 pubmed publisher
    ..The fact that both decreased and increased CAND1-CUL1 interactions result in reduced SCF(TIR1) activity in vivo strongly supports the hypothesis that CAND1-mediated cycling is required for optimal SCF function. ..