转录组分析表明，生长素促进独脚金内酯诱导甜瓜幼苗下胚轴不定根的生长。

Transcriptome analysis reveals that auxin promotes strigolactone-induced adventitious root growth in the hypocotyl of melon seedlings.

作者信息

Li Jingrui, Fan Mi, Zhang Qinqin, Lü Guiyun, Wu Xiaolei, Gong Binbin, Wang Yubo, Zhang Ying, Gao Hongbo

机构信息

College of Horticulture, Hebei Agricultural University, Baoding, China.

Collaborative Innovation Center of Vegetable Industry in Hebei, Baoding, China.

出版信息

Front Plant Sci. 2023 Jun 12;14:1192340. doi: 10.3389/fpls.2023.1192340. eCollection 2023.

DOI:10.3389/fpls.2023.1192340

PMID:37377810

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10292653/

Abstract

INTRODUCTION

Strigolactone (SL) and auxin are two important phytohormones involved in plant root development, but whether they show synergistic or mutual promotion effects during adventitious root (AR) formation has not been adequately explored.

METHODS

In this study, we investigated the mechanisms of GR24 (synthetic SL) and indole-3-acetic acid (IAA; a type of auxin) in the formation of ARs using melon as the study material.

RESULTS

Morphological measurements showed that the AR number, length, superficial area, and volume under the GR24 treatment were 1.60-3.27, 1.58-3.99, 2.06-3.42, and 3.00-6.11 times greater than those of the control group, respectively, at 6-10 days; the GR24+IAA treatment further promoted AR formation in melon seedlings, and the AR number, length, superficial area, and volume under the GR24+IAA treatment were 1.44-1.51, 1.28-1.73, 1.19-1.83, and 1.31-1.87 times greater than those obtained with the GR24 treatment, respectively. Transcriptome analysis revealed 2,742, 3,352, and 2,321 differentially expressed genes (DEGs) identified from the GR24 control, GR24+IAA control, and GR24+IAA GR24 comparisons, respectively. The GR24 treatment and GR24+IAA treatment affected auxin and SL synthesis as well as components of the phytohormone signal transduction pathway, such as auxin, brassinosteroid (BR), ethylene (ETH), cytokinin (CK), gibberellin (GA), and abscisic acid (ABA). The concentrations of auxin, GA, zeatin (ZT), and ABA were evaluated using high-performance liquid chromatography (HPLC). From 6 to 10 days, the auxin, GA, and ZT contents in the GR24 treatment group were increased by 11.48%-15.34%, 11.83%-19.50%, and 22.52%-66.17%, respectively, compared to the control group, and these features were increased by 22.00%-31.20%, 21.29%-25.75%, 51.76%-98.96%, respectively, in the GR24+IAA treatment group compared with the control group. Compared to that in the control, the ABA content decreased by 10.30%-11.83% in the GR24 treatment group and decreased by 18.78%-24.00% in the GR24+IAA treatment group at 6-10 days.

DISCUSSION

Our study revealed an interaction between strigolactone and auxin in the induction of AR formation in melon seedlings by affecting the expression of genes related to plant hormone pathways and contents.

摘要

引言

独脚金内酯（SL）和生长素是参与植物根系发育的两种重要植物激素，但它们在不定根（AR）形成过程中是否表现出协同或相互促进作用尚未得到充分研究。

方法

在本研究中，我们以甜瓜为研究材料，研究了GR24（合成SL）和吲哚-3-乙酸（IAA；一种生长素）在不定根形成中的作用机制。

结果

形态学测量表明，在6-10天时，GR24处理组的不定根数量、长度、表面积和体积分别比对照组大1.60-3.27倍、1.58-3.99倍、2.06-3.42倍和3.00-6.11倍；GR24+IAA处理进一步促进了甜瓜幼苗不定根的形成，GR24+IAA处理组的不定根数量、长度、表面积和体积分别比GR24处理组大1.44-1.51倍、1.28-1.73倍、1.19-1.83倍和1.31-1.87倍。转录组分析分别从GR24_对照、GR24+IAA_对照和GR24+IAA_GR24比较中鉴定出2742、3352和2321个差异表达基因（DEG）。GR24处理和GR24+IAA处理影响生长素和SL的合成以及植物激素信号转导途径的成分，如生长素、油菜素内酯（BR）、乙烯（ETH）、细胞分裂素（CK）、赤霉素（GA）和脱落酸（ABA）。使用高效液相色谱（HPLC）评估生长素、GA、玉米素（ZT）和ABA的浓度。在6-10天时，与对照组相比，GR24处理组的生长素、GA和ZT含量分别增加了11.48%-15.34%、11.83%-19.50%和22.52%-66.17%，与对照组相比，GR24+IAA处理组的这些特征分别增加了22.00%-31.20%、21.29%-25.75%、51.76%-98.96%。与对照组相比，在6-10天时，GR24处理组的ABA含量下降了10.30%-11.83%，GR24+IAA处理组的ABA含量下降了18.78%-24.00%。