Loss of GSNOR1 Function Leads to Compromised Auxin Signaling and Polar Auxin Transport.
Cross talk between phytohormones, nitric oxide (NO), and auxin has been implicated in the control of plant growth and development. Two recent reports indicate that NO promoted auxin signaling but inhibited auxin transport probably through S-nitrosylation. However, genetic evidence for the effect of S-nitrosylation on auxin physiology has been lacking. In this study, we used a genetic approach to understand the broader role of S-nitrosylation in auxin physiology in Arabidopsis. We compared auxin signaling and transport in Col-0 and gsnor1-3, a loss-of-function GSNOR1 mutant defective in protein de-nitrosylation. Our results showed that auxin signaling was impaired in the gsnor1-3 mutant as revealed by significantly reduced DR5-GUS/DR5-GFP accumulation and compromised degradation of AXR3NT-GUS, a useful reporter in interrogating auxin-mediated degradation of Aux/IAA by auxin receptors. In addition, polar auxin transport was compromised in gsnor1-3, which was correlated with universally reduced levels of PIN or GFP-PIN proteins in the roots of the mutant in a manner independent of transcription and 26S proteasome degradation. Our results suggest that S-nitrosylation and GSNOR1-mediated de-nitrosylation contribute to auxin physiology, and impaired auxin signaling and compromised auxin transport are responsible for the auxin-related morphological phenotypes displayed by the gsnor1-3 mutant.
College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
Ya-Fei
YF
Shi
College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
Da-Li
DL
Wang
College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
Chao
C
Wang
Department of Horticultural Science, Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN 55108, USA.
Angela Hendrickson
AH
Culler
Department of Horticultural Science, Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN 55108, USA.
Molly A
MA
Kreiser
Department of Horticultural Science, Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN 55108, USA.
Jayanti
J
Suresh
Department of Horticultural Science, Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN 55108, USA.
Jerry D
JD
Cohen
College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
Jianwei
J
Pan
Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Barbara
B
Baker
College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China. Electronic address: jzliu@zjnu.cn.
Jian-Zhong
JZ
Liu
D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005966:Glucuronidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism*; D018522:Gravitropism / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000378:metabolism; D018869:Heat-Shock Response / Q000187:drug effects; D007210:Indoleacetic Acids / Q000378:metabolism*; D009154:Mutation; D015538:Nitrosation; D010641:Phenotype; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D059748:Proteolysis / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D026422:S-Nitrosoglutathione / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects
D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D012333:RNA, Messenger; D049452:Green Fluorescent Proteins; D026422:S-Nitrosoglutathione; D005980:Glutathione Reductase; C521253:S-nitrosoglutathione reductase, Arabidopsis; D005966:Glucuronidase; D046988:Proteasome Endopeptidase Complex
Arabidopsis; S-nitrosoglutathione reductase (GSNOR); S-nitrosylation; auxin signaling; auxin transport; phytohormone cross talk