title: Mutations in the TIR1 auxin receptor that increase affinity for auxin/indole-3-acetic acid proteins result in auxin hypersensitivity.
abstract: The phytohormone auxin regulates virtually every aspect of plant development. The hormone directly mediates the interaction between the two members of the auxin coreceptor complex, a TRANSPORT INHIBITOR RESPONSE (TIR1)/AUXIN SIGNALING F-BOX protein and an AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) transcriptional repressor. To learn more about the interaction between these proteins, a mutant screen was performed using the yeast (Saccharomyces cerevisiae) two-hybrid system in Arabidopsis (Arabidopsis thaliana). Two tir1 mutations were identified that increased interaction with Aux/IAAs. The D170E and M473L mutations increase affinity between TIR1 and the degron motif of Aux/IAAs and enhance the activity of the SCF(TIR1) complex. This resulted in faster degradation of Aux/IAAs and increased transcription of auxin-responsive genes in the plant. Plants carrying the pTIR1:tir1 D170E/M473L-Myc transgene exhibit diverse developmental defects during plant growth and display an auxin-hypersensitive phenotype. This work demonstrates that changes in the leucine-rich repeat domain of the TIR1 auxin coreceptor can alter the properties of SCF(TIR1).
authors.affiliation: Howard Hughes Medical Institute and Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California 92093, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Yu
authors.forename: Britney L
authors.initials: BL
authors.lastname: Moss
authors.forename: Seunghee S
authors.initials: SS
authors.lastname: Jang
authors.forename: Michael
authors.initials: M
authors.lastname: Prigge
authors.forename: Eric
authors.initials: E
authors.lastname: Klavins
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Nemhauser
authors.forename: Mark
authors.initials: M
authors.lastname: Estelle
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000494:pharmacology; D019943:Amino Acid Substitution; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D044783:F-Box Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D007210:Indoleacetic Acids / Q000378:metabolism / Q000494:pharmacology; D009154:Mutation; D010641:Phenotype; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology*; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction; D020798:Two-Hybrid System Techniques
chemical_list: D029681:Arabidopsis Proteins; D044783:F-Box Proteins; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; C501405:TIR1 protein, Arabidopsis; D015084:2,4-Dichlorophenoxyacetic Acid; C030737:indoleacetic acid; D044843:SKP Cullin F-Box Protein Ligases
references.citation: Plant Mol Biol. 2009 Mar;69(4):489-502
references.pmid: 19083152
references.citation: Plant J. 1998 Dec;16(6):735-43
references.pmid: 10069079
references.citation: Plant Physiol. 2012 Sep;160(1):135-42
references.pmid: 22843664
references.citation: Proc Natl Acad Sci U S A. 2002 Aug 20;99(17):11519-24
references.pmid: 12169662
references.citation: Cold Spring Harb Perspect Biol. 2009 Nov;1(5):a001545
references.pmid: 20066117
references.citation: Nature. 2001 Nov 15;414(6861):271-6
references.pmid: 11713520
references.citation: Trends Plant Sci. 2001 Sep;6(9):420-5
references.pmid: 11544131
references.citation: Curr Biol. 2011 Mar 22;21(6):520-5
references.pmid: 21396817
references.citation: Nature. 2005 May 26;435(7041):446-51
references.pmid: 15917798
references.citation: Nat Rev Mol Cell Biol. 2005 Jan;6(1):9-20
references.pmid: 15688063
references.citation: Plant Cell. 2010 Jun;22(6):1749-61
references.pmid: 20562234
references.citation: Curr Biol. 2010 Nov 9;20(21):1907-12
references.pmid: 20951049
references.citation: Curr Opin Plant Biol. 2007 Oct;10(5):453-60
references.pmid: 17900969
references.citation: Plant Cell. 2001 Oct;13(10):2349-60
references.pmid: 11595806
references.citation: EMBO J. 2005 May 18;24(10):1874-85
references.pmid: 15889151
references.citation: Nat Chem Biol. 2012 Apr 01;8(5):477-85
references.pmid: 22466420
references.citation: Plant J. 2000 Mar;21(6):553-62
references.pmid: 10758506
references.citation: Plant Cell. 2001 Dec;13(12):2809-22
references.pmid: 11752389
references.citation: Proc Natl Acad Sci U S A. 2009 Dec 29;106(52):22540-5
references.pmid: 20018756
references.citation: Genes Dev. 1998 Jan 15;12(2):198-207
references.pmid: 9436980
references.citation: Proc Natl Acad Sci U S A. 2010 Mar 2;107(9):4477-82
references.pmid: 20142497
references.citation: Plant Cell. 2004 Feb;16(2):533-43
references.pmid: 14742873
references.citation: Cell Mol Life Sci. 2004 Jul;61(13):1546-61
references.pmid: 15224180
references.citation: ACS Chem Biol. 2012 Mar 16;7(3):590-8
references.pmid: 22234040
references.citation: Cold Spring Harb Perspect Biol. 2010 Jun;2(6):a001537
references.pmid: 20516130
references.citation: Plant Cell. 2006 Mar;18(3):699-714
references.pmid: 16489122
references.citation: Cold Spring Harb Perspect Biol. 2010 Apr;2(4):a001487
references.pmid: 20452945
references.citation: Cold Spring Harb Perspect Biol. 2009 Dec;1(6):a001628
references.pmid: 20457563
references.citation: Nat Methods. 2009 Dec;6(12):917-22
references.pmid: 19915560
references.citation: BMC Cell Biol. 2011 Feb 11;12:8
references.pmid: 21314938
references.citation: Dev Cell. 2005 Jul;9(1):109-19
references.pmid: 15992545
references.citation: Proc Natl Acad Sci U S A. 2012 Dec 4;109(49):E3350-7
references.pmid: 23150568
references.citation: Nature. 2007 Apr 5;446(7136):640-5
references.pmid: 17410169
references.citation: Science. 2008 Mar 7;319(5868):1384-6
references.pmid: 18258861
references.citation: Nature. 2005 May 26;435(7041):441-5
references.pmid: 15917797
references.citation: Ann Bot. 2005 Apr;95(5):707-35
references.pmid: 15749753
references.citation: Science. 2006 Apr 21;312(5772):436-9
references.pmid: 16627744
references.citation: Annu Rev Cell Dev Biol. 2008;24:55-80
references.pmid: 18631113