Identification of the NAC Family and a Functional Analysis of <i>NoNAC36a</i> Under Flooding Stress in Watercress (<i>Nasturtium officinale</i> R.Br.)

Watercress (<i>Nasturtium officinale</i> R.Br.) is a cruciferous aquatic vegetable that possesses significant nutritional value. The NAC family is a transcription factor family specific to plants that play an important role in regulating plant responses to abiotic stress. In order to inv...

Full description

Saved in:
Bibliographic Details
Main Authors: Qiang Ding, Jiajun Ran, Xiaoshan Chen, Zhanyuan Gao, Xiaojun Qian, Chenyang Zhang, Suchong Deng, Yunlou Shen, Yaolong Wang, Ying Li, Xilin Hou
Format: Article
Language:English
Published: MDPI AG 2024-11-01
Series:Horticulturae
Subjects:
Online Access:https://www.mdpi.com/2311-7524/10/11/1219
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Watercress (<i>Nasturtium officinale</i> R.Br.) is a cruciferous aquatic vegetable that possesses significant nutritional value. The NAC family is a transcription factor family specific to plants that play an important role in regulating plant responses to abiotic stress. In order to investigate the response of NAC genes to flooding stress in watercress, we conducted a study on the <i>NoNAC</i> family. In this study, a total of 119 <i>NoNAC</i> genes were obtained through genome-wide identification. Phylogenetic analysis indicated that the <i>NoNAC</i> family members can be categorized into ten subgroups. The results of gene structure analysis revealed that each branch within the subgroups exhibited similar motif composition and gene structure. The heatmap analysis showed that several <i>NoNAC</i> genes demonstrated tissue-specific expression patterns, suggesting their potential as regulators of associated tissue development. As an aquatic plant, watercress serves as a valuable material for investigating plant resistance to flooding stress. This study found that flooding can significantly increase the watercress plant height, which is a typical escape strategy under flooding. The analysis of the expression of <i>NoNAC</i> genes in the stem transcriptome after flooding indicated that only <i>NoNAC36a</i> consistently exhibited significant differential changes and down-regulated expression at the three time points of flooding treatment. This suggests that <i>NoNAC36a</i> may be involved in regulating watercress plant height increases under flooding stress. The utilization of a virus-induced gene silencing assay to investigate the biological function of <i>NoNAC36a</i> revealed that <i>NoNAC36a</i> silencing caused cell elongation and expansion, thus increasing watercress plant height. The yeast one-hybrid and dual luciferase assays demonstrated that NoNAC36a binds the promoter of <i>NoXTH33</i> and inhibits its expression. Subsequently, the results of yeast two-hybrid, luciferase complementary, and pull-down assays revealed the interaction between NoMOB1A and NoNAC36a in vivo and in vitro. Sequence alignment indicated that NoMOB1A and AtMOB1A share an identical amino acid sequence. RT-qPCR analysis indicated that flooding prompted the expression of <i>NoMOB1A</i> in stems. Thus, it is speculated that <i>NoMOB1A</i> may exhibit functions similar to <i>AtMOB1A</i> and that the up-regulation of <i>NoMOB1A</i> expression in stems may facilitate an increase in plant height under flooding. In summary, the <i>NoNAC</i> family was analyzed, and revealed a regulatory network centered on <i>NoNAC36a</i> that facilitates watercress resistance to flooding stress. This study enhanced the understanding of the <i>NoNAC</i> genes and established a theoretical foundation for investigating plant flooding tolerance.
ISSN:2311-7524