Nitric oxide influences auxin signaling through S-nitrosylation of the Arabidopsis TRANSPORT INHIBITOR RESPONSE 1 auxin receptor

The present study investigated the changes in total and individual glucosinolates (GSLs) in roots and leaves of different clubroot-resistant and -susceptible oilseed rape cultivars following artificial inoculation with Plasmodiophora brassicae isolates with different virulence. The results showed significant differences in clubroot incidence and severity as well as in the amount of total and individual glucosinolates between oilseed rape cultivars in response to virulence of the pathogen. Single among with total aliphatic and total indolic glucosinolate contents were significantly lower in leaves of susceptible cultivars compared to resistant ones due to the infection. Similarly, single and total aliphatic as well as indolic glucosinolate contents in roots were lower in susceptible cultivars compared to resistant cultivars analyzed. The different isolates of P. brassicae seem to differ in their ability to reduce gluconasturtiin contents in the host. The more aggressive isolate P1 (+) might be able to suppress gluconasturtiin synthesis of the host in a more pronounced manner compared to the isolate P1. A possible interaction of breakdown products of glucobrassicin with the auxin receptor transport inhibitor response 1 (TIR1) is hypothesized and its possible effects on auxin signaling in roots and leaves of resistant and susceptible cultivars is discussed. A potential interplay between aliphatic and indolic glucosinolates that might be involved in water homeostasis in resistant cultivars is explained.

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Faculty Opinions recommendation of The AFB4 auxin receptor is a negative regulator of auxin signaling in seedlings.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.9378965.10348054 ◽

2011 ◽

Author(s):

Miltos Tsiantis

Keyword(s):

Negative Regulator ◽

Auxin Signaling ◽

Auxin Receptor

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Overexpression of the Auxin Receptor AFB3 in Arabidopsis Results in Salt Stress Resistance and the Modulation of NAC4 and SZF1

International Journal of Molecular Sciences ◽

10.3390/ijms21249528 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9528

Author(s):

Fernanda Garrido-Vargas ◽

Tamara Godoy ◽

Ricardo Tejos ◽

José Antonio O’Brien

Keyword(s):

Salt Stress ◽

Stress Response ◽

Growth And Development ◽

Root Architecture ◽

Crop Production ◽

Lateral Roots ◽

Auxin Signaling ◽

Auxin Receptor ◽

Salt Stress Response ◽

Regulatory Pathways

Soil salinity is a key problem for crop production worldwide. High salt concentration in soil negatively modulates plant growth and development. In roots, salinity affects the growth and development of both primary and lateral roots. The phytohormone auxin regulates various developmental processes during the plant’s life cycle, including several aspects of root architecture. Auxin signaling involves the perception by specialized receptors which module several regulatory pathways. Despite their redundancy, previous studies have shown that their functions can also be context-specific depending on tissue, developmental or environmental cues. Here we show that the over-expression of Auxin Signaling F-Box 3 receptor results in an increased resistance to salinity in terms of root architecture and germination. We also studied possible downstream signaling components to further characterize the role of auxin in response to salt stress. We identify the transcription factor SZF1 as a key component in auxin-dependent salt stress response through the regulation of NAC4. These results give lights of an auxin-dependent mechanism that leads to the modulation of root system architecture in response to salt identifying a hormonal cascade important for stress response.

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RETRACTED: The AFB4 Auxin Receptor Is a Negative Regulator of Auxin Signaling in Seedlings

Current Biology ◽

10.1016/j.cub.2011.02.029 ◽

2011 ◽

Vol 21 (6) ◽

pp. 520-525 ◽

Cited By ~ 57

Author(s):

Katie Greenham ◽

Aaron Santner ◽

Cristina Castillejo ◽

Sutton Mooney ◽

Ilkka Sairanen ◽

...

Keyword(s):

Negative Regulator ◽

Auxin Signaling ◽

Auxin Receptor

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A synthetic approach reveals a highly sensitive maize auxin response circuit

10.1101/844100 ◽

2019 ◽

Author(s):

Román Ramos Báez ◽

Yuli Buckley ◽

Han Yu ◽

Zongliang Chen ◽

Andrea Gallavotti ◽

...

Keyword(s):

Auxin Signaling ◽

Synthetic Approach ◽

Auxin Response ◽

Auxin Receptor ◽

Repressor Proteins ◽

Highly Sensitive ◽

Signaling Function ◽

Wide Range ◽

Signaling Components

Auxin plays a key role across all land plants in growth and developmental processes. Although auxin signaling function has diverged and expanded, differences in the molecular functions of signaling components have largely been characterized in Arabidopsis thaliana. Here, we used the Auxin Response Circuit recapitulated in Saccharomyces cerevisiae (ARCSc) system to functionally annotate maize auxin signaling components, focusing on genes expressed during development of ear and tassel inflorescences. All 16 maize Auxin (Aux)/Indole-3-Acetic Acid (IAA) repressor proteins are degraded in response to auxin, with rates that depended on both receptor and repressor identity. When fused to the maize TOPLESS (TPL) homolog RAMOSA1 ENHANCER LOCUS2 (REL2), maize Aux/IAAs were able to repress AUXIN RESPONSE FACTOR (ARF) transcriptional activity. A complete auxin response circuit comprised of all maize components, including ZmAFB2/3 b1 maize AUXIN SIGNALING F-BOX (AFB) receptor, was found to be fully functional. The ZmAFB2/3 b1 auxin receptor was found to be more sensitive to hormone than AtAFB2 and allowed for rapid circuit activation upon auxin addition. These results validate the conserved role of predicted auxin response genes in maize, as well as provide evidence that a synthetic approach can facilitate broader comparative studies across the wide range of species with sequenced genomes.

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Expression and Role of Biosynthetic, Transporter, Receptor, and Responsive Genes for Auxin Signaling during Clubroot Disease Development

International Journal of Molecular Sciences ◽

10.3390/ijms21155554 ◽

2020 ◽

Vol 21 (15) ◽

pp. 5554

Author(s):

Arif Hasan Khan Robin ◽

Gopal Saha ◽

Rawnak Laila ◽

Jong-In Park ◽

Hoy-Taek Kim ◽

...

Keyword(s):

Plasmodiophora Brassicae ◽

Fold Increase ◽

Auxin Signaling ◽

Post Inoculation ◽

Disease Development ◽

Secondary Phases ◽

Auxin Receptor ◽

Clubroot Disease ◽

Root Tissues

Auxins play a pivotal role in clubroot development caused by the obligate biotroph Plasmodiophora brassicae. In this study, we investigated the pattern of expression of 23 genes related to auxin biosynthesis, reception, and transport in Chinese cabbage (Brassica rapa) after inoculation with P. brassicae. The predicted proteins identified, based on the 23 selected auxin-related genes, were from protein kinase, receptor kinase, auxin responsive, auxin efflux carrier, transcriptional regulator, and the auxin-repressed protein family. These proteins differed in amino acids residue, molecular weights, isoelectric points, chromosomal location, and subcellular localization. Leaf and root tissues showed dynamic and organ-specific variation in expression of auxin-related genes. The BrGH3.3 gene, involved in auxin signaling, exhibited 84.4-fold increase in expression in root tissues compared to leaf tissues as an average of all samples. This gene accounted for 4.8-, 2.6-, and 5.1-fold higher expression at 3, 14, and 28 days post inoculation (dpi) in the inoculated root tissues compared to mock-treated roots. BrNIT1, an auxin signaling gene, and BrPIN1, an auxin transporter, were remarkably induced during both cortex infection at 14 dpi and gall formation at 28 dpi. BrDCK1, an auxin receptor, was upregulated during cortex infection at 14 dpi. The BrLAX1 gene, associated with root hair development, was induced at 1 dpi in infected roots, indicating its importance in primary infection. More interestingly, a significantly higher expression of BrARP1, an auxin-repressed gene, at both the primary and secondary phases of infection indicated a dynamic response of the host plant towards its resistance against P. brassicae. The results of this study improve our current understanding of the role of auxin-related genes in clubroot disease development.

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Fine control of aerenchyma and lateral root development through AUX/IAA- and ARF-dependent auxin signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1907181116 ◽

2019 ◽

Vol 116 (41) ◽

pp. 20770-20775 ◽

Cited By ~ 13

Author(s):

Takaki Yamauchi ◽

Akihiro Tanaka ◽

Hiroki Inahashi ◽

Naoko K. Nishizawa ◽

Nobuhiro Tsutsumi ◽

...

Keyword(s):

Root Development ◽

Molecular Mechanisms ◽

Auxin Transport ◽

Lateral Roots ◽

Cortical Cell ◽

Dominant Negative ◽

Dominant Negative Effect ◽

Auxin Signaling ◽

Transport Inhibitor ◽

Auxin Transport Inhibitor

Lateral roots (LRs) are derived from a parental root and contribute to water and nutrient uptake from the soil. Auxin/indole-3-acetic acid protein (AUX/IAA; IAA) and auxin response factor (ARF)-mediated signaling are essential for LR formation. Lysigenous aerenchyma, a gas space created by cortical cell death, aids internal oxygen transport within plants. Rice (Oryza sativa) forms lysigenous aerenchyma constitutively under aerobic conditions and increases its formation under oxygen-deficient conditions; however, the molecular mechanisms regulating constitutive aerenchyma (CA) formation remain unclear. LR number is reduced by the dominant-negative effect of a mutated AUX/IAA protein in the iaa13 mutant. We found that CA formation is also reduced in iaa13. We have identified ARF19 as an interactor of IAA13 and identified a lateral organ boundary domain (LBD)-containing protein (LBD1-8) as a target of ARF19. IAA13, ARF19, and LBD1-8 were highly expressed in the cortex and LR primordia, suggesting that these genes function in the initiation of CA and LR formation. Restoration of LBD1-8 expression recovered aerenchyma formation and partly recovered LR formation in the iaa13 background, in which LBD1-8 expression was reduced. An auxin transport inhibitor suppressed CA and LR formation, and a natural auxin stimulated CA formation in the presence of the auxin transport inhibitor. Our findings suggest that CA and LR formation are both regulated through AUX/IAA- and ARF-dependent auxin signaling. The initiation of CA formation lagged that of LR formation, which indicates that the formation of CA and LR are regulated differently by auxin signaling during root development in rice.

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Retraction Notice to: The AFB4 Auxin Receptor Is a Negative Regulator of Auxin Signaling in Seedlings

Current Biology ◽

10.1016/j.cub.2015.02.062 ◽

2015 ◽

Vol 25 (6) ◽

pp. 819

Author(s):

Katie Greenham ◽

Aaron Santner ◽

Cristina Castillejo ◽

Sutton Mooney ◽

Ilkka Sairanen ◽

...

Keyword(s):

Negative Regulator ◽

Auxin Signaling ◽

Auxin Receptor ◽

Retraction Notice

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Selective auxin agonists induce specific AUX/IAA protein degradation to modulate plant development

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1809037116 ◽

2019 ◽

Vol 116 (13) ◽

pp. 6463-6472 ◽

Cited By ~ 6

Author(s):

Thomas Vain ◽

Sara Raggi ◽

Noel Ferro ◽

Deepak Kumar Barange ◽

Martin Kieffer ◽

...

Keyword(s):

Small Molecules ◽

Chromatin Remodeling ◽

Plant Development ◽

Chemical Biology ◽

Auxin Signaling ◽

Transcriptional Repressors ◽

Transport Inhibitor ◽

Specific Subset ◽

Protein Ligases ◽

Indole 3 Acetic Acid

Auxin phytohormones control most aspects of plant development through a complex and interconnected signaling network. In the presence of auxin, AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) transcriptional repressors are targeted for degradation by the SKP1-CULLIN1-F-BOX (SCF) ubiquitin-protein ligases containing TRANSPORT INHIBITOR RESISTANT 1/AUXIN SIGNALING F-BOX (TIR1/AFB). CULLIN1-neddylation is required for SCFTIR1/AFBfunctionality, as exemplified by mutants deficient in the NEDD8-activating enzyme subunit AUXIN-RESISTANT 1 (AXR1). Here, we report a chemical biology screen that identifies small molecules requiring AXR1 to modulate plant development. We selected four molecules of interest, RubNeddin 1 to 4 (RN1 to -4), among which RN3 and RN4 trigger selective auxin responses at transcriptional, biochemical, and morphological levels. This selective activity is explained by their ability to consistently promote the interaction between TIR1 and a specific subset of AUX/IAA proteins, stimulating the degradation of particular AUX/IAA combinations. Finally, we performed a genetic screen using RN4, the RN with the greatest potential for dissecting auxin perception, which revealed that the chromatin remodeling ATPase BRAHMA is implicated in auxin-mediated apical hook development. These results demonstrate the power of selective auxin agonists to dissect auxin perception for plant developmental functions, as well as offering opportunities to discover new molecular players involved in auxin responses.

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