Methods in Phytohormone Detection and Quantification: 2022

Editorial

10 July 2023

Editorial: Methods in phytohormone detection and quantification: 2022

Da Cao

and

Man He

5,377 views

5 citations

Editors

Impact

Review

24 March 2022

Regulation of Phytohormones on the Growth and Development of Plant Root Hair

Mengxia Li

, 4 more and

Yongjun Lin

The regulation network of phytohormones on root hair initiation and elongation in Arabidopsis. GL2 inhibits the expression of ROOT HAIR DEFECTIVE 6 (RHD6) and RHD6 LIKE1 (RSL1), which are positive regulators of root hair initiation and elongation. RHD6 and RSL1 promote the expression of RSL2 and RSL4, which in turn promote root hair elongation by upregulating the expression of elongation genes. JAZ protein, a repressor of JA signal transduction, inhibits RHD6 transcription and interferes with the interaction between RHD6 and RSL1. JAZ protein also inhibits the transcription of EIN3 and EIL1 in the ethylene signaling pathway. EIN3/EIL1 can form a complex with RHD6/RSL1 to promote root hair initiation, and EIN3 binds to the promoter region of RSL4 to promote its transcription. The auxin response factor ARF5 also binds to the RSL4 promoter region to induce RSL4 expression, and the auxin response factor ARF7 and ARF19 bind to the promoter region of ERU to induce ERU expression. GA negatively regulates the expression of root hair elongation genes through DELLA-mediated signal transduction. ABA induces the accumulation of OBP4 protein, and OBP4 binds to the RSL2 promoter region to inhibit RSL2 expression. ABA also induces the expression of AtOXI1 and other root hair initiation-related genes by H2O2 production. CK can promote root hair elongation by promoting RSL4 expression. SL induces root hair elongation-related gene expression through the MAX2-mediated signal transduction pathway. BR negatively regulates the expression of root hair elongation-related genes. →, positive regulation; ┤, negative regulation. JA, jasmonate; ETH, ethylene; CK, cytokinin; GA, gibberellin; BR, brassinosteroid; SL, strigolactone; and ABA, abscisic acid.

The tubular-shaped unicellular extensions of plant epidermal cells known as root hairs are important components of plant roots and play crucial roles in absorbing nutrients and water and in responding to stress. The growth and development of root hair include, mainly, fate determination of root hair cells, root hair initiation, and root hair elongation. Phytohormones play important regulatory roles as signal molecules in the growth and development of root hair. In this review, we describe the regulatory roles of auxin, ethylene (ETH), jasmonate (JA), abscisic acid (ABA), gibberellin (GA), strigolactone (SL), cytokinin (CK), and brassinosteroid (BR) in the growth and development of plant root hairs. Auxin, ETH, and CK play positive regulation while BR plays negative regulation in the fate determination of root hair cells; Auxin, ETH, JA, CK, and ABA play positive regulation while BR plays negative regulation in the root hair initiation; Auxin, ETH, CK, and JA play positive regulation while BR, GA, and ABA play negative regulation in the root hair elongation. Phytohormones regulate root hair growth and development mainly by regulating transcription of root hair associated genes, including WEREWOLF (WER), GLABRA2 (GL2), CAPRICE (CPC), and HAIR DEFECTIVE 6 (RHD6). Auxin and ETH play vital roles in this regulation, with JA, ABA, SL, and BR interacting with auxin and ETH to regulate further the growth and development of root hairs.

8,445 views

46 citations

The content of IAA (A), ABA (B), and GA3 (C) in the leaves of S. portulacastrum under salt stress.

Original Research

23 September 2022

De novo transcriptome analysis of high-salinity stress-induced antioxidant activity and plant phytohormone alterations in Sesuvium portulacastrum

YiQing Chen

, 5 more and

Ying Zhang

2,473 views

9 citations

Review

30 September 2021

Phytohormone-Based Regulation of Trichome Development

Jinxing Li

, 6 more and

Wansheng Chen

Phytohormones affect plant growth and development. Many phytohormones are involved in the initiation of trichome development, which can help prevent damage from UV radiation and insect bites and produce fragrance, flavors, and compounds used as pharmaceuticals. Phytohormones promote the participation of transcription factors in the initiation of trichome development; for example, the transcription factors HDZIP, bHLH and MYB interact and form transcriptional complexes to regulate trichome development. Jasmonic acid (JA) mediates the progression of the endoreduplication cycle to increase the number of multicellular trichomes or trichome size. Moreover, there is crosstalk between phytohormones, and some phytohormones interact with each other to affect trichome development. Several new techniques, such as the CRISPR-Cas9 system and single-cell transcriptomics, are available for investigating gene function, determining the trajectory of individual trichome cells and elucidating the regulatory network underlying trichome cell lineages. This review discusses recent advances in the modulation of trichome development by phytohormones, emphasizes the differences and similarities between phytohormones initially present in trichomes and provides suggestions for future research.

9,940 views

24 citations

Methods

06 April 2021

A Tobacco Syringe Agroinfiltration-Based Method for a Phytohormone Transporter Activity Assay Using Endogenous Substrates

Jiangzhe Zhao

, 4 more and

Kewei Zhang

8,054 views

12 citations

Methods

19 November 2020

A Rapid Method for Quantifying RNA and Phytohormones From a Small Amount of Plant Tissue

Da Cao

, 2 more and

Christine A. Beveridge

Phytohormones are involved in most plant physiological processes and the quantification of endogenous phytohormone levels and related gene expressions is an important approach to studying phytohormone functions. However, the quantification of phytohormones is still challenging due to their extremely low endogenous level in plant tissues and their high chemical diversity. Therefore, developing a method to simultaneously quantify phytohormone levels and RNA would strongly facilitate comparative analyses of phytohormones and gene expression. The present work reports a convenient extraction protocol enabling multivariate analysis of phytohormones and RNA from small amounts of plant material (around 10 mg). This high-throughput ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method demonstrates quantification of phytohormones and their related metabolites from four plant hormone classes: cytokinin, auxin, abscisic acid, and gibberellin. The UPLC-MS/MS method can quantify thirteen phytohormones and their metabolites simultaneously in 14 min. To validate the developed method, we determined the dynamic profiles of phytohormones and gene expressions in small axillary shoot buds in garden pea. This new method is applicable to quantification analysis of gene expression and multiple phytohormone classes in small amounts of plant materials. The results obtained using this method in axillary buds provide a basis for understanding the phytohormone functions in shoot branching regulation.

10,101 views

22 citations