Plant Hormone Research Research Articles

Spatio-temporal plant hormonomics: from tissue to subcellular resolution.

Due to technological advances in mass spectrometry, significant progress has been achieved recently in plant hormone research. Nowadays, plant hormonomics is well established as a fully integrated scientific field focused on the analysis of phytohormones, mainly on their isolation, identification, and spatiotemporal quantification in plants. This review represents a comprehensive meta-study of the advances in the phytohormone analysis by mass spectrometry over the past decade. To address current trends and future perspectives, Web of Science data were systematically collected and key features such as mass spectrometry-based analyses were evaluated using multivariate data analysis methods. Our findings showed that plant hormonomics is currently divided into targeted and untargeted approaches. Both aim to miniaturize the sample, allowing high-resolution quantification to be covered in plant organs as well as subcellular compartments. Therefore, we can study plant hormone biosynthesis, metabolism, and signalling at a spatio-temporal resolution. Moreover, this trend has recently been accelerated by technological advances such as fluorescence-activated cell sorting or mass spectrometry imaging.

The Active Phytohormone in Microalgae: The Characteristics, Efficient Detection, and Their Adversity Resistance Applications.

Phytohormones are a class of small organic molecules that are widely used in higher plants and microalgae as chemical messengers. Phytohormones play a regulatory role in the physiological metabolism of cells, including promoting cell division, increasing stress tolerance, and improving photosynthetic efficiency, and thereby increasing biomass, oil, chlorophyll, and protein content. However, traditional abiotic stress methods for inducing the accumulation of energy storage substances in microalgae, such as high light intensity, high salinity, and heavy metals, will affect the growth of microalgae and will ultimately limit the efficient accumulation of energy storage substances. Therefore, the addition of phytohormones not only helps to reduce production costs but also improves the efficiency of biofuel utilization. However, accurate and sensitive phytohormones determination and analytical methods are the basis for plant hormone research. In this study, the characteristics of phytohormones in microalgae and research progress for regulating the accumulation of energy storage substances in microalgae by exogenous phytohormones, combined with abiotic stress conditions at home and abroad, are summarized. The possible metabolic mechanism of phytohormones in microalgae is discussed, and possible future research directions are put forward, which provide a theoretical basis for the application of phytohormones in microalgae.

Fluorescent biosensors illuminating plant hormone research.

Phytohormones act as key regulators of plant growth that coordinate developmental and physiological processes across cells, tissues and organs. As such, their levels and distribution are highly dynamic owing to changes in their biosynthesis, transport, modification and degradation that occur over space and time. Fluorescent biosensors represent ideal tools to track these dynamics with high spatiotemporal resolution in a minimally invasive manner. Substantial progress has been made in generating a diverse set of hormone sensors with recent FRET biosensors for visualising hormone concentrations complementing information provided by transcriptional, translational and degron-based reporters. In this review, we provide an update on fluorescent biosensor designs, examine the key properties that constitute an ideal hormone biosensor, discuss the use of these sensors in conjunction with in vivo hormone perturbations and highlight the latest discoveries made using these tools.

Plant hormone functions and interactions in biological systems

Plant hormone functions and interactions in biological systems

Research Progress on the Mechanism of GA and ABA during Seed Germination

The dormancy and germination of seeds are determined by the balance between the embryo growth potential and the binding force imposed by the seed coat. The germination of different seeds is not synchronized, and the stimulus required to promote germination varies greatly. Before germination, the seeds need to undergo water absorption, reactivate metabolic activities and redifferentiate embryonic tissues to mobilize nutrients stored in seeds and initiate meristematic activities. The transition from dry seeds to seedlings is highly sensitive to different environmental conditions, especially light, temperature and water. This response to environmental signals is regulated by one or more hormones. Various plant hormones regulate seed germination through highly complex interactions. Among them, the role of GA (gibberellin) and ABA (Abscisic acid) in regulating seed germination is particularly critical. This article reviewed the mechanisms by which GA and ABA control seed dormancy at the molecular level, and discussed the way they interact with other hormones. Finally, the development direction of plant hormone research on seed germination is prospected.

オーキシンの生合成経路と合成部位( 総説 最近の植物ホルモン研究の動向 II 生合成)

オーキシンの生合成経路と合成部位( 総説 最近の植物ホルモン研究の動向 II 生合成)

オーキシンの信号伝達( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

オーキシンの信号伝達( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

受容と信号伝達-エチレン : エチレンの受容と情報伝達機構( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

受容と信号伝達-エチレン : エチレンの受容と情報伝達機構( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

サイトカイニンの受容と情報伝達( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

サイトカイニンの受容と情報伝達( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

ジベリンシグナル伝達因子 : DELLAファミリーを中心として( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

ジベリンシグナル伝達因子 : DELLAファミリーを中心として( 最近の植物ホルモン研究の動向 I 受容と信号伝達)

Stability of housekeeping gene expression in Arabidopsis thaliana seedlings under differing macronutrient and hormonal conditions

Recent progress in plant hormone and macronutrient research is largely associated with characterising the molecular mechanisms of their actions. Quantitative reverse transcription-PCR is a powerful technique that enables elucidation of regulatory relationships through quantifying transcript levels, but its reliability requires precise normalization. We compared eight Arabidopsis thaliana housekeeping genes for expression stability after treatment with cytokinins, auxins, ethylene and after macronutrient level manipulation. The expression stability of housekeeping genes in cytokinin series was studied in wide spectrum of plants treated with different adenine- and phenylurea-type cytokinins as well as in plants with controlled overexpression of agrobacterial isopentenyltransferase. NormFinder and geNorm software were used to predict a unique set of genes as best for particular hormone groups. Generally, 18S rRNA, GAPC, and ACT were confirmed as less stable; and UBQ10, UBC, and EF-1α exhibited increased stability. Based on geNorm pairwise variation analysis, we confirmed accurate normalization required at least three reference genes.

Visualisation of abscisic acid and 12-oxo-phytodienoic acid in immature Phaseolus vulgaris L. seeds using desorption electrospray ionisation-imaging mass spectrometry

The plant hormone abscisic acid (ABA) and the jasmonic acid related-compound 12-oxo-phytodienoic acid (OPDA) play crucial roles in seed development, dormancy, and germination. However, a lack of suitable techniques for visualising plant hormones has restricted the investigation of their biological mechanisms. In the present study, desorption electrospray ionisation-imaging mass spectrometry (DESI-IMS), a powerful tool for visualising metabolites in biological tissues, was used to visualise ABA and OPDA in immature Phaseolus vulgaris L. seed sections. The mass spectra, peak values and chemical formulae obtained from the analysis of seed sections were consistent with those determined for ABA and OPDA standards, as were the precursor and major fragment ions observed in tandem mass spectrometry (MS/MS) imaging. Furthermore, the precursor and fragment ion images showed similar distribution patterns. In addition, the localisation of ABA and OPDA using DESI-IMS was confirmed using liquid chromatography-MS/MS (LC-MS/MS). The results indicated that ABA was mainly distributed in the radical and cotyledon of the embryo, whereas OPDA was distributed exclusively in external structures, such as the hilum and seed coat. The present study is the first to report the visualisation of plant hormones using IMS, and demonstrates that DESI-IMS is a promising technique for future plant hormone research.

Editorial: When Chemistry Meets Biology - Generating Innovative Concepts, Methods and Tools for Scientific Discovery in the Plant Sciences.

Editorial: When Chemistry Meets Biology - Generating Innovative Concepts, Methods and Tools for Scientific Discovery in the Plant Sciences.

Surface Plasmon Resonance Based Recent Advances in Understanding Plant Development and Related Processes

Since its introduction in the early 1990s, SPR has now become a powerful research tool for studying specificity, affinity and real time kinetics of a broad range of biomolecular interactions, including protein-DNA, protein-protein, protein-carbohydrate, protein-RNA and protein-lipid interactions. Surface plasmon resonance (SPR) has provided crucial information on the mechanisms of molecular interactions accompanying varied aspects of plant development. The structure-function relationship of various lectins depends on the quaternary arrangement of its monomers. Novel findings have been made in plant hormone research using SPR as a technique. Thus, new salicylic acid binding proteins (SABPs) have been identified in Arabidopsis. These include α-ketoglutarate dehydrogenase E2 subunit, glutathione S-transferases, the oligopeptidases TOP2 and TOP1, and members of GAPDH protein family. By immobilizing biotin-labelled DELLA peptides on the sensor chip and AtGID1a [Arabidopsis gibberellic acid (GA) receptor] as analyte, GA4 has been observed to maximally enhance binding between DELLA and GID1. Molecularly imprinted monolayer (MIM)-decorated SPR detection method precisely differentiates between similar plant hormones, such as, IAA, 1H-indole-3-butyric acid (IBA) and kinetin (KT), with detection limits around sub-picomolar range. Coronatine Insensitive-1 (COI1) has been shown to act as a jasmonic acid receptor using SPR. Ricin, a plant toxin, was detected at a concentration 2,500 times less than the minimum lethal dose (200 ng.ml-1) using a SPR biosensor. Real time binding kinetic studies of viral proteins (VirE1 and VirE2) and ssDNA using SPR have shown that their binding is strongly influenced by substrate and it occurs at poly T sequences and not at polyA and dsDNA. An interaction between the replicase protein (p93) of cucumber necrosis tombusvirus (CNV) with the host protein, Hsp 70 (molecular chaperone), has revealed the potential role of Hsp90 in the assembly of viral replicase. SPR analysis from a small library of phytochemicals has shown ellagitannin geraniin as one of the most potent inhibitor of Hsp90 (a stabilizer of many oncoproteins). Future applications of SPR technique are likely to provide tremendous inputs into the molecular understanding of plant development and related processes.

From Facts and False Routes: How Plant Hormone Research Developed

Our understanding of how plant hormones work has tremendously increased over the last decades. However, such progress was not possible without those who laid the foundation of the work which was sometimes much more tedious in early days than today. Therefore, we thought it timely to follow-up on historical aspects of plant hormone research. The development in the field of auxins, cytokinins, gibberellins, abscisic acid, jasmonates, brassinosteroids, and ethylene are accompanied with personal recollections. Plant hormones cannot go without plant growth regulators which have been developed for commercial reasons, but are also used in many cases nowadays as tools to investigate a specific role of a hormone in planta. This issue is also hopefully a useful collection for those scientists who want to get an overview of how their “favorite hormone” started.

Sugars take a central position in plant growth, development and, stress responses. A focus on apical dominance.

Sugars take a central position in plant growth, development and, stress responses. A focus on apical dominance.

Molecular Mechanisms of Ethylene–Auxin Interaction

During the century-long history of plant hormone research, the focus in this area has shifted from the original physiological experiments to molecular, genetic, biochemical, and, more recently, genomic approaches. During this journey, we have learned about the many effects these natural compounds have on plant growth and development at the morphological and molecular levels. We have also uncovered how these molecules are sensed by the plant cell and how they trigger signaling cascades that relay information to the nucleus, ultimately culminating in a transcriptional cascade.

Cloning, expression and purification of orthologous membrane proteins: a general protocol for preparation of the histidine sensor kinase ETR1 from different species

Orthologous proteins do not necessarily share the same function in all species and those sharing the same function might employ a modified catalytic mechanism. Thus, comparative analysis of homologous or orthologous proteins from different organisms can provide detailed information on the function and the mechanism of an entire protein family. The sensor kinase ETR1 from Arabidopsis thaliana has been well characterized by genetic, physiological and biochemical studies. However, as further model plants are coming into focus for plant hormone research, a general protocol for isolation and purification of orthologous ETR1 proteins seems instrumental for a detailed molecular analysis of this protein family. In this study, we describe the native purification of recombinant ETR1 from Arabidopsis thaliana by mild solubilization with the zwitter-ionic detergent Fos-Choline-14 and single-step purification by immobilized metal ion affinity chromatography. The same protocol was successfully applied for the purification of the orthologous proteins from the moss Physcomitrella patens subsp. patens and the tomato Lycopersicon esculentum. The successful transfer of the purification protocol to proteins of the same family which share sequence identity of 63-80% only suggests that this protocol presents a general purification strategy which is likely to apply also to the purification of other members of the sensor histidine kinase family.

Phytohormone targeting in plant tissues

Background The identification and quantification of plant hormones in plant tissues are necessary for physiological studies of their metabolism and mode of action. The major problem associated with plant hormone analysis is that the amount of phytohormones present endogenously in plant tissues is very low, usually in the range of fmol to pmol/g fresh weight. Methods Homogenization and extraction with organic solvents was done in one microcentrifuge tube and accelerated by crushing the plant material in a vibration mill. The extracts from minute amounts of fresh plant material were immediately purified using a solid-phase extraction (C18, C8, Oasis™ HLB cartridges)in combination with ion-exchange and/or immunoaffinity purification. A fast chromatography technique, the ultra performance liquid chromatography (Acquity TM UPLC,Waters) was coupled to triple quadrupole mass spectrometer (Xevo TM TQ MS, Waters) equipped with an electrospray interface (ESI) and the unique performance of collision cell – ScanWave TM . The mass spectrometric conditions were optimized for each analyte and quantification was obtained by multiple reaction monitoring (MRM) of precursors and the appropriate product ions. Results and discussion We found that a combination of different sorbents, reverse phases and ion-exchange phases, was the best tool in the one-step purification, giving a total extraction recovery ranging between 50-80% for all studied biologically active compounds. In MRM mode, the detection limit for most of phytohormones (cytokinins [1,2], auxins [3], abscisic acid [4], gibberellins, brassinosteroids) as well as phenolic acids [5] and mammalian steroids [6] was close to 1 fmol and achieved linear range was at least five orders of magnitude. Use of our procedures can allow the quantification of plant hormones and their derivatives (in total 145 compounds) in very limited amounts of material, ca. 100 mg FW. The methods provide substantial improvements in terms of robustness, sensitivity, selectivity, convenience, through-put and cost-effectiveness over previous methods published. Conclusions The application of new analytical approaches based on UPLC separation makes possible a new direction in plant hormone research. We believe that UPLC-ESI(+) MS/MS technology can be used for fast and sensitive quantitative analysis showing reproducibility in the plant hormones profiling in different tree extracts.

Plant Hormones: Metabolism, Signaling and Crosstalk

Plant Hormones: Metabolism, Signaling and Crosstalk