Cleavage of INDOLE-3-ACETIC ACID INDUCIBLE28 mRNA by MicroRNA847 Upregulates Auxin Signaling to Modulate Cell Proliferation and Lateral Organ Growth in Arabidopsis

Although not fully understood, molecular communication in the rhizosphere plays an important role regulating traits involved in plant–bacteria association. Burkholderia phytofirmans PsJN is a well-known plant-growth-promoting bacterium, which establishes rhizospheric and endophytic colonization in different plants. A competent colonization is essential for plant-growth-promoting effects produced by bacteria. Using appropriate mutant strains of B. phytofirmans, we obtained evidence for the importance of N-acyl homoserine lactone-mediated (quorum sensing) cell-to-cell communication in efficient colonization of Arabidopsis thaliana plants and the establishment of a beneficial interaction. We also observed that bacterial degradation of the auxin indole-3-acetic acid (IAA) plays a key role in plant-growth-promoting traits and is necessary for efficient rhizosphere colonization. Wildtype B. phytofirmans but not the iacC mutant in IAA mineralization is able to restore promotion effects in roots of A. thaliana in the presence of exogenously added IAA, indicating the importance of this trait for promoting primary root length. Using a transgenic A. thaliana line with suppressed auxin signaling (miR393) and analyzing the expression of auxin receptors in wild-type inoculated plants, we provide evidence that auxin signaling in plants is necessary for the growth promotion effects produced by B. phytofirmans. The interplay between ethylene and auxin signaling was also confirmed by the response of the plant to a 1-aminocyclopropane-1-carboxylate deaminase bacterial mutant strain.

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Control of vein-forming, striped gene expression by auxin signaling

BMC Biology ◽

10.1186/s12915-021-01143-9 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Anmol Krishna ◽

Jason Gardiner ◽

Tyler J. Donner ◽

Enrico Scarpella

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Acetic Acid ◽

Target Gene ◽

Target Genes ◽

Auxin Signaling ◽

Plant Leaves ◽

Vein Formation ◽

Indole 3 Acetic Acid ◽

Differential Affinity

Abstract Background Activation of gene expression in striped domains is a key building block of biological patterning, from the recursive formation of veins in plant leaves to that of ribs and vertebrae in our bodies. In animals, gene expression is activated in striped domains by the differential affinity of broadly expressed transcription factors for their target genes and the combinatorial interaction between such target genes. In plants, how gene expression is activated in striped domains is instead unknown. We address this question for the broadly expressed MONOPTEROS (MP) transcription factor and its target gene ARABIDOPSIS THALIANA HOMEOBOX FACTOR8 (ATHB8). Results We find that ATHB8 promotes vein formation and that such vein-forming function depends on both levels of ATHB8 expression and width of ATHB8 expression domains. We further find that ATHB8 expression is activated in striped domains by a combination of (1) activation of ATHB8 expression through binding of peak levels of MP to a low-affinity MP-binding site in the ATHB8 promoter and (2) repression of ATHB8 expression by MP target genes of the AUXIN/INDOLE-3-ACETIC-ACID-INDUCIBLE family. Conclusions Our findings suggest that a common regulatory logic controls activation of gene expression in striped domains in both plants and animals despite the independent evolution of their multicellularity.

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Transcriptome-wide analysis of auxin-induced carotenoid accumulation in Chlorella microalgae

10.1101/334102 ◽

2018 ◽

Cited By ~ 1

Author(s):

Faisal Alsenani ◽

Taylor J. Wass ◽

Ruijuan Ma ◽

Eladl Eltanahy ◽

Michael E. Netzel ◽

...

Keyword(s):

Acetic Acid ◽

Abscisic Acid ◽

De Novo ◽

Higher Plants ◽

Abiotic Stress Tolerance ◽

Auxin Signaling ◽

Rna Seq ◽

Carotenoid Accumulation ◽

Close Relationship ◽

Indole 3 Acetic Acid

AbstractMicroalgae are a commercially viable route for the production of carotenoids, including β-carotene and astaxanthin. In the current study, the commercially relevant microalga, Chlorella sp. BR2 was treated with four plant hormones: indole-3-acetic acid, salicylic acid, abscisic acid and methyl jasmonate, over a range of dosages and screened for enhanced carotenoid production. Indole-3-acetic acid was the only hormone with an inductive effect on carotenoid accumulation. As such, the transcriptome under the condition with the highest carotenoid increase was profiled using RNA-Seq and expressed sequences reconstructed with de novo assembly. This allowed for the profiling of transcriptome-wide changes following auxin treatment, revealing the active pathway components of auxininduced carotenogenesis. Data analysis specified the differentially expressed genes involved in auxin biosynthesis and signal transduction, which suggest a close relationship to equivalent pathways in higher plants. However unlike in plants, the ancient ABP1/SCFSKP2A/IBR5-mediated pathways for auxin response likely acted as the primary signaling route in Chlorella. As carotenoids are precursors for abscisic acid, the findings suggest a causative link between auxin signaling and abiotic stress tolerance.HighlightTranscriptomics of plant hormone-treated Chlorella revealed the active pathway components of auxin-induced carotenogenesis and included the ancient ABP1/SCFSKP2A/IBR5-mediated pathways. The manuscript presents the first documented transcriptomic data of auxin-treated microalgae.

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Control of Vein-Forming, Striped Gene-Expression by Auxin Signaling

10.1101/2020.09.28.317644 ◽

2020 ◽

Author(s):

Anmol Krishna ◽

Jason Gardiner ◽

Tyler J. Donner ◽

Enrico Scarpella

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Acetic Acid ◽

Target Gene ◽

Target Genes ◽

Auxin Signaling ◽

Plant Leaves ◽

Vein Formation ◽

Indole 3 Acetic Acid ◽

Differential Affinity

ABSTRACTActivation of gene expression in striped domains is a key building block of biological patterning, from the recursive formation of veins in plant leaves to that of ribs and vertebrae in our bodies. In animals, gene expression is activated in striped domains by the differential affinity of broadly expressed transcription factors for their target genes and the combinatorial interaction between such target genes. In plants, how gene expression is activated in striped domains is instead unknown. We address this question for the broadly expressed MONOPTEROS (MP) transcription factor and its target gene ARABIDOPSIS THALIANA HOMEOBOX FACTOR8 (ATHB8). We find that ATHB8 promotes vein formation and that such vein-forming function depends on both levels of ATHB8 expression and width of ATHB8 expression domains. We further find that ATHB8 expression is activated in striped domains by a combination of (1) activation of ATHB8 expression through binding of peak levels of MP to a low-affinity MP-binding site in the ATHB8 promoter and (2) repression of ATHB8 expression by MP target genes of the INDOLE-3-ACETIC-ACID-INDUCIBLE family such as BODENLOS. Our findings suggest that a common regulatory logic controls activation of gene expression in striped domains in both plants and animals despite the independent evolution of their multicellularity.

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Identical Amino Acid Substitutions in the Repression Domain of Auxin/Indole-3-Acetic Acid Proteins Have Contrasting Effects on Auxin Signaling

PLANT PHYSIOLOGY ◽

10.1104/pp.110.171322 ◽

2011 ◽

Vol 155 (3) ◽

pp. 1252-1263 ◽

Cited By ~ 28

Author(s):

Hanbing Li ◽

Shiv B. Tiwari ◽

Gretchen Hagen ◽

Tom J. Guilfoyle

Keyword(s):

Acetic Acid ◽

Amino Acid ◽

Auxin Signaling ◽

Amino Acid Substitutions ◽

Identical Amino Acid ◽

Indole 3 Acetic Acid ◽

Repression Domain

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Altered levels of primary metabolites in response to exogenous indole-3-acetic acid in wild type and auxin signaling mutants of Arabidopsis thaliana: A capillary electrophoresis-mass spectrometry analysis

Plant Biotechnology ◽

10.5511/plantbiotechnology.15.0116a ◽

2015 ◽

Vol 32 (1) ◽

pp. 65-79 ◽

Cited By ~ 6

Author(s):

Aya Anegawa ◽

Miwa Ohnishi ◽

Daisuke Takagi ◽

Chikahiro Miyake ◽

Chizuko Shichijo ◽

...

Keyword(s):

Mass Spectrometry ◽

Arabidopsis Thaliana ◽

Acetic Acid ◽

Capillary Electrophoresis ◽

Mass Spectrometry Analysis ◽

Auxin Signaling ◽

Wild Type ◽

Primary Metabolites ◽

Spectrometry Analysis ◽

Indole 3 Acetic Acid

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Effects of Indole Amides on Lettuce and Onion Germination and Growth

Zeitschrift für Naturforschung C ◽

10.1515/znc-2011-9-1008 ◽

2011 ◽

Vol 66 (9-10) ◽

pp. 485-490

Author(s):

Thiago F. Borgati ◽

Maria Amelia D. Boaventura

Keyword(s):

Cell Proliferation ◽

Acetic Acid ◽

Shoot Growth ◽

Herbicidal Activity ◽

Cell Proliferation And Differentiation ◽

Proliferation And Differentiation ◽

Inhibitory Compound ◽

Germination And Growth ◽

Indole 3 Acetic Acid ◽

Plant Germination

3Auxins, such as indole-3-acetic acid (IAA), are important in plant germination and growth, while physiological polyamines, such as putrescine, are involved in cell proliferation and differentiation, and their concentrations increase during germination. In this work, novel indole amides were synthesized in good yields by monoacylation of morpholine and unprotected symmetrical diamines with indole-3-carboxylic acid, a putative metabolite of IAA, possessing no auxin-like activity. These amides were tested for their effects on seed germination and growth of the radicles and shoots of Lactuca sativa (lettuce) and Allium cepa (onion) seedlings, at 100.0, 1.0, and 0.01 μM concentrations. Germination was generally stimulated, with the exception of amide , derived from morpholine, at 100 μM. On radicle and shoot growth, the effect of these compounds was predominantly inhibitory. Compound 3 was the best inhibitor of growth of lettuce and onion, at the highest concentration. Amides, such as propanil, among others, are described as having herbicidal activity

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Molecular machinery of auxin synthesis, secretion, and perception in the unicellular chlorophyte alga Chlorella sorokiniana UTEX 1230

10.1101/172833 ◽

2017 ◽

Cited By ~ 2

Author(s):

Maya Khasin ◽

Rebecca R. Cahoon ◽

Kenneth W. Nickerson ◽

Wayne R. Riekhof

Keyword(s):

Acetic Acid ◽

Auxin Transport ◽

Higher Plants ◽

Chlorella Sorokiniana ◽

Auxin Signaling ◽

Seed Plants ◽

Auxin Receptor ◽

Auxin Binding ◽

Auxin Synthesis ◽

Indole 3 Acetic Acid

AbstractIndole-3-acetic acid is a ubiquitous small molecule found in all domains of life. It is the predominant and most active auxin in seed plants, where it coordinates a variety of complex growth and development processes. The potential origin of auxin signaling in algae remains a matter of some controversy. In order to clarify the evolutionary context of algal auxin signaling, we undertook a genomic survey to assess whether auxin acts as a signaling molecule in the emerging model chlorophyte Chlorella sorokiniana UTEX 1230. C. sorokiniana produces the auxin indole-3-acetic acid (IAA), which was present in both the cell pellet and in the supernatant at a concentration of ~ 1 nM, and its genome encodes orthologs of genes related to auxin synthesis, transport, and signaling in higher plants. Candidate orthologs for the canonical AUX/IAA signaling pathway were not found; however, auxin-binding protein 1 (ABP1), an alternate auxin receptor, is present and highly conserved at essential auxin binding and zinc coordinating residues. Additionally, candidate orthologs for PIN proteins, responsible for intercellular, vectorial auxin transport in higher plants, were not found, but PILs (PIN-Like) proteins, a recently discovered family that mediates intracellular auxin transport, were identified. The distribution of auxin related gene in this unicellular chlorophyte demonstrates that a core suite of auxin signaling components was present early in the evolution of plants. Understanding the simplified auxin signaling pathways in chlorophytes will aid in understanding phytohormone signaling and crosstalk in seed plants, and in understanding the diversification and integration of developmental signals during the evolution of multicellular plants.

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Changes in endogenous levels of IAA and PAA in rice seed during development, prediction of auxin signaling proteins and docking for its binding efficiency with auxin molecules

African Crop Science Journal ◽

10.4314/acsj.v29i3.1 ◽

1970 ◽

Vol 29 (3) ◽

pp. 325-337

Author(s):

V.M. Jhala ◽

K.S. Chudasama ◽

V.S. Thaker

Keyword(s):

Acetic Acid ◽

Higher Plants ◽

Rice Genome ◽

Auxin Signaling ◽

Signaling Proteins ◽

Rice Seed ◽

Genome Data ◽

Sink Size ◽

Rice Seeds ◽

Indole 3 Acetic Acid

Indole-3-acetic acid (IAA) and phenyl acetic acid (PAA) are two major physiologically active auxins, found in higher plants. The objective of this study was to evaluate changes in the endogenous levels of IAA and PAA in rice (Oryza sativa) seed and predict probable transporter and efflux (signaling) proteins for docking with auxins from the available rice genome data. IAA and PAA were estimated during rice seed development using sensitive and specific antibodies against each hormone. The levels of IAA and PAA were higher when sink size development was at its peak, suggesting an important role played by the auxin in sink size development of rice seed. Furthermore, auxin binding transporters proteins of rice were confirmed for docking purpose and compared with Arabidopsis and maize proteins. In this context, PAA docked with known IAA proteins; although, docking score of IAA was higher than that of PAA in rice seed. Twelve genes of the auxin efflux carrier (PIN family) of rice were also analysed for phylogeny relatedness with Arabidopsis and maize, to further understanding auxin concentrations and efflux within rice seeds. The predicted PIN proteins for IAA efflux of rice showed docking affinities with PAA, revealed its role in maintaining physiological concentrations of auxins in rice seeds.

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