Molecular Characterization and Expression Analysis of the Na+/H+ Exchanger Gene Family in Capsicum annuum L.

Abstract

The Na+/H+ exchangers (NHXs) are a class of transporters involved in ion balance during plant growth and abiotic stress. We performed systematic bioinformatic identification and expression-characteristic analysis of CaNHX genes in pepper to provide a theoretical basis for pepper breeding and practical production. At the whole-genome level, the members of the CaNHX gene family of cultivated and wild pepper were systematically identified using bioinformatics methods. Sequence alignment and phylogenetic tree construction were performed using MEGA X software, and the gene functional domain, conserved motif, and gene structure were analyzed and visualized. At the same time, the co-expression network of CaNHX genes was analyzed, and salt-stress analysis and fluorescence quantitative verification of the Zunla-1 cultivar under stress conditions were performed. A total of 9 CaNHX genes were identified, which have typical functional domains of the Na+/H+ exchanger gene. The physical and chemical properties of the protein showed that the protein was hydrophilic, with a size of 503–1146 amino acids. Analysis of the gene structure showed that Chr08 was the most localized chromosome, with 8–24 exons. Cis-acting element analysis showed that it mainly contains cis-acting elements such as light response, salicylic acid response, defense, and stress response. Transcriptom and co-expression network analysis showed that under stress, the co-expressed genes of CaNHX genes in roots and leaves were more obvious than those in the control group, including ABA, IAA, and salt. The transcriptome and co-expression were verified by qRT-PCR. In this study, the CaNHX genes were identified at the genome level of pepper, which provides a theoretical foundation for improving the stress resistance, production, development, and utilization of pepper in genetic breeding.

Genome-Wide Identification, Primary Functional Characterization of the NHX Gene Family in Canavalia rosea, and Their Possible Roles for Adaptation to Tropical Coral Reefs

“…Analysis of gene structures and conserved motifs showed that CrNHX s exhibited high conservation during evolution. Interestingly, in the plant monovalent cation/proton antiporters (CPAs) superfamily, the NHX families often show multi-intron characteristics compared with other ion channel gene families, for example, the cation/H + exchanger (CHX) families [ 33 , 64 ], and in other species, the introns of NHX families seem to be fairly conservative [ 23 , 24 , 65 ]. It is reported that multiple numbers of exons in genes might be positively correlated with active chromatin structures, which could represent a type of possible gene regulation pattern for epigenetic or expression complexity [ 24 ].…”

In vitro fermentation reveals an interplay relationship between oat β-glucan and human gut Bacteroides and their potential role in regulating gut cytokines

“…The detailed procedure of the evolutionary analysis was conducted according to a previous report. 21…”

Genome‐wide identification and expression analysis of Na+/H+antiporter (NHX) genes in tomato under salt stress

“…SOS3 activates the SOS2 protein kinase, and the SOS2-SOS3 complex then activates SOS1/NHX7 by phosphorylation to efflux Na + ions out of the cell (Halfter et al, 2000;Liu et al, 2000;Shi et al, 2003). Previous reports have documented six NHX genes in Medicago truncatula (Sandhu et al, 2018), nine NHX genes in Capsicum annuum (Luo et al, 2021), five NHX genes in Beta vulgaris (Wu et al, 2019), six NHX genes in Vitis vinifera (Ayadi et al, 2020), 10 NHX genes in Glycine max (Chen et al, 2015), eight NHX genes in Populus trichocarpa (Tian et al, 2017), 10 NHX genes in Punica granatum (Dong et al, 2021), and eight NHX genes in Actinidia chinensis were identified (Liu et al, 2023). Such variation among the NHX gene numbers of plant species indicated that gene duplications or loss events occurred during species evolution, which also provided an opportunity to expand the NHX gene family by generation functionally divert new genes (Huang et al, 2022).…”