Use of Chemical Biology to Understand Auxin Metabolism, Signaling, and Polar Transport

Hayashi, Ken‐ichiro; Overvoorde, Paul J.

doi:10.1002/9781118742921.ch4.1

Cited by 4 publications

(3 citation statements)

References 154 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The use of pharmacological inhibitors, identified through chemical biology approaches, has proven to be a powerful strategy that has greatly assisted in unravelling the details of auxin transporter trafficking mechanisms (reviewed by Hayashi & Overvoorde, ; and Doyle et al ., 2015b). We previously employed such a strategy, revealing that the AA analogue ES8 selectively inhibits an early endoplasmic reticulum (ER)‐to‐Golgi secretory pathway, regulated by the adenosine diphosphate (ADP) ribosylation factor guanine nucleotide exchange factors (ARF‐GEFs) GNOM and GNOM‐LIKE 1 (GNL1), involved in rootward targeting of PIN1 without affecting the polarity of shootward plasma membrane proteins (Doyle et al ., 2015a).…”

Section: Discussionmentioning

confidence: 99%

A role for the auxin precursor anthranilic acid in root gravitropism via regulation of PIN‐FORMED protein polarity and relocalisation in Arabidopsis

et al. 2019

View full text Add to dashboard Cite

Summary distribution of auxin within plant tissues is of great importance for developmental plasticity, including root gravitropic growth. Auxin flow is directed by the subcellular polar distribution and dynamic relocalisation of auxin transporters such as the PIN‐FORMED (PIN) efflux carriers, which can be influenced by the main natural plant auxin indole‐3‐acetic acid (IAA). Anthranilic acid (AA) is an important early precursor of IAA and previously published studies with AA analogues have suggested that AA may also regulate PIN localisation. Using Arabidopsis thaliana as a model species, we studied an AA‐deficient mutant displaying agravitropic root growth, treated seedlings with AA and AA analogues and transformed lines to over‐produce AA while inhibiting its conversion to downstream IAA precursors. We showed that AA rescues root gravitropic growth in the AA‐deficient mutant at concentrations that do not rescue IAA levels. Overproduction of AA affects root gravitropism without affecting IAA levels. Treatments with, or deficiency in, AA result in defects in PIN polarity and gravistimulus‐induced PIN relocalisation in root cells. Our results revealed a previously unknown role for AA in the regulation of PIN subcellular localisation and dynamics involved in root gravitropism, which is independent of its better known role in IAA biosynthesis.

show abstract

Section: Discussionmentioning

confidence: 99%

A role for the auxin precursor anthranilic acid in root gravitropism via regulation of PIN‐FORMED protein polarity and relocalisation in Arabidopsis

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Elucidation of the cellular and physiological roles of auxin and its mode of action is historically reliant on the use of diverse bioactive small molecules, ranging from natural metabolites from plants or microbes to synthetic compounds. In recent years, the rapid development of chemical biology has contributed significantly to enhance our understanding of auxin biology, which has been comprehensively summarized in several recent reviews (De Rybel et al, 2009a; Hayashi and Overvoorde, 2013; Ma and Robert, 2014). Here, we intend to concentrate on the employment of auxin agonists and antagonists in interrogating the molecular mechanisms underlying auxin signaling and its regulation.…”

Section: Agonist and Antagonist Moleculesmentioning

confidence: 99%

“…Various synthetic compounds capable of eliciting auxin-like responses were identified in the early years of auxin research and used as auxin agonists to examine and manipulate auxin signaling pathways (De Rybel et al, 2009a; Hayashi and Overvoorde, 2013; Ma and Robert, 2014), most notably 1-naphthaleneacetic acid (1-NAA) and the widely used herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (picloram) (Figure 2A). Genetic analyses of resistance to these compounds or their derivatives assisted in the isolation of a number of key components in auxin signaling, such as AUXIN-RESISTANT1 (AXR1) to AXR3, AXR5, AXR6, AFB4, and AFB5 (Estelle and Somerville, 1987; Woodward and Bartel, 2005).…”

Section: Agonist and Antagonist Moleculesmentioning

confidence: 99%

Unraveling plant hormone signaling through the use of small molecules

Rigal

Robert

2014

Front. Plant Sci.

View full text Add to dashboard Cite

Plants have acquired the capacity to grow continuously and adjust their morphology in response to endogenous and external signals, leading to a high architectural plasticity. The dynamic and differential distribution of phytohormones is an essential factor in these developmental changes. Phytohormone perception is a fast but complex process modulating specific developmental reprogramming. In recent years, chemical genomics or the use of small molecules to modulate target protein function has emerged as a powerful strategy to study complex biological processes in plants such as hormone signaling. Small molecules can be applied in a conditional, dose-dependent and reversible manner, with the advantage of circumventing the limitations of lethality and functional redundancy inherent to traditional mutant screens. High-throughput screening of diverse chemical libraries has led to the identification of bioactive molecules able to induce plant hormone-related phenotypes. Characterization of the cognate targets and pathways of those molecules has allowed the identification of novel regulatory components, providing new insights into the molecular mechanisms of plant hormone signaling. An extensive structure-activity relationship (SAR) analysis of the natural phytohormones, their designed synthetic analogs and newly identified bioactive molecules has led to the determination of the structural requirements essential for their bioactivity. In this review, we will summarize the so far identified small molecules and their structural variants targeting specific phytohormone signaling pathways. We will highlight how the SAR analyses have enabled better interrogation of the molecular mechanisms of phytohormone responses. Finally, we will discuss how labeled/tagged hormone analogs can be exploited, as compelling tools to better understand hormone signaling and transport mechanisms.

show abstract