NAC transcription factors play crucial roles in plant growth, development and stress responses. Previously, we preliminarily identified that the transcription factor AeNAC83 gene was significantly up-regulated under salt stress in okra (Abelmoschus esculentus). Herein, we cloned the nuclear-localized AeNAC83 from okra and identified its possible role in salt stress response and plant growth. The down-regulation of AeNAC83 caused by virus-induced gene silencing enhanced plant sensitivity to salt stress and increased the biomass accumulation of okra seedlings. Meanwhile, AeNAC83-overexpression Arabidopsis lines improved salt tolerance and exhibited many altered phenotypes, including small rosette, short primary roots, and promoted crown roots and root hairs. RNA-seq showed numerous genes at the transcriptional level that changed significantly in the AeNAC83-overexpression transgenic and the wild Arabidopsis with or without NaCl treatment, respectively. The expression of most phenylpropanoid and flavonoid biosynthesis-related genes was largely induced by salt stress. While genes encoding key proteins involved in photosynthesis were almost declined dramatically in AeNAC83-overexpression transgenic plants, and NaCl treatment further resulted in the down-regulation of these genes. Furthermore, DEGs encoding various plant hormone signal pathways were also identified. These results indicate that AeNAC83 is involved in resistance to salt stress and plant growth.

Soil salinization is one of the abiotic stresses that inhibit plant growth and development, which seriously restricts global crop production. WRKY transcription factors play an important role in regulating plant responses to stress such as salt stress. In our previous study, two WRKY family genes from okra, AeWRKY32 and AeWRKY70, were significantly up-regulated and down-regulated, respectively, in response to salt stress. In this study, subcellular localization showed that they were localized to the nucleus. The down-regulation of AeWRKY32 and AeWRKY70 via whole plant virus-induced gene silencing (VIGS) increased and decreased plant sensitivity to salt stress, respectively. Ectopic expression of AeWRKY32 and AeWRKY70 led to promoted and reduced salt tolerance in transgenic Arabidopsis, respectively. There was no significant difference between transgenic plants and wild type (WT) without salt treatment. Salt stress significantly inhibited plant growth. The decrease of chlorophyll content and the increase of anthocyanin content in AeWRKY32-overexpressed transgenic plants were lower than those in the WT, while AeWRKY70-overexpressed plants had the opposite effect. Under salt stress, the AeWRKY70-overexpressed plants had the highest malondialdehyde (MDA) content, followed by the WT, and the lowest in AeWRKY32-overexpressed plants. The hydrogen peroxide (H₂O₂) content and superoxide anion (O₂^•−) generation rate were only slightly increased. Moreover, salt stress significantly increased plant proline content and antioxidant enzyme activities, which was highest in AeWRKY70-overexpressed plants except superoxide dismutase (SOD). Taken together, these results suggest that AeWRKY32 and AeWRKY70 play positive and negative roles in plant in response to salt stress, respectively.

Soybean, a globally significant and versatile crop, serves as a vital source of both oil and protein. However, environmental factors such as soil salinization pose substantial challenges to its cultivation, adversely affecting both yield and quality. Enhancing the salt tolerance of soybeans can mitigate yield losses and promote the development of the soybean industry. Members of the plant-specific transcription factor family NAC play crucial roles in plant adaptation to abiotic stress conditions. In this study, we screened the soybean GmNAC family genes potentially involved in the salt stress response and identified 18 GmNAC genes that may function during the early stages of salt stress. Among these, the GmNAC035 gene exhibited a rapid increase in expression within one hour of salt treatment, with its expression being induced by abscisic acid (ABA) and methyl jasmonate (MeJA), suggesting its significant role in the soybean salt stress response. We further elucidated the role of GmNAC035 in soybean salt tolerance. GmNAC035, a nuclear-localized transcriptional activator, enhances salt tolerance when overexpressed in Arabidopsis, reducing oxidative damage and boosting the expression of stress-responsive genes. It achieves this by regulating key stress response pathways, including the SOS pathway, calcium signaling, and ABA signaling. These findings highlight the potential of GmNAC035 as a genetic engineering target to improve crop salt tolerance.

Soybean is an important and versatile crop worldwide. Enhancing soybean architecture offers a potential method to increase yield. Plant-specific transcription factors play a crucial, yet often unnoticed, role in regulating plant growth and development. GRF-INTERACTING FACTOR (GIF) genes are plant-specific transcription factors; however, their functions in soybean remain poorly understood. Eight GmGIF members were identified in soybean (Glycine max L.). Phylogenetic analysis divided the eight GmGIF proteins into three groups. In this study, we focused on the role of GmGIF5 owing to its high expression level in the meristem. Subcellular localization and transcriptional activity analysis showed that GmGIF5 was localized to the nucleus and has self-transactivation ability. To elucidate the biological function of GmGIF5, we constructed transgenic Arabidopsis lines overexpressing the gene. Phenotype observations indicated that the overexpression of GmGIF5 contributed to larger leaves, higher plants, wider stems, and larger seeds. The organs of GmGIF5 overexpression lines exhibited larger sizes primarily due to an increase in cell size rather than cell number. RNA sequencing was performed to investigate the underlying mechanism for these effects, showing that differentially expressed genes in overexpression lines were mainly enriched in cell wall modification processes. Our study provides new clues for an understanding of the roles of the GmGIF family in soybean, which can promote the further application of these genes in genetic breeding.

Excessive selenium has gradually become a potential environmentally hazardous element for all organisms. Limited knowledge is available regarding the toxic mechanism of selenium in pepper, so the quantitative proteomics of phosphorylation was studied by Tandem Mass Tag approaches. A total of 4434 phosphorylation sites were identified on 2058 proteins, of which 3749 sites of 1919 proteins contained quantitative information. In the Se/mock (seedlings without Se treatment) comparison group, the number of upregulated phosphoproteins (658) was significantly higher than that of the downregulated ones (61). Systematic bioinformatics analysis, including protein annotation, functional classification, subcellular localization, and cluster analysis was performed. A total of 33 over-represented motifs were found in serine phosphorylation, and the most frequent motif was ‘sP’ (308 occurrences). According to KEGG enrichment analysis, the upregulated phosphorylated proteins (DPPs) were most strongly associated with the ’phenylpropanoid biosynthesis’ and ’nicotinate and nicotinamide metabolism’ pathways, while those that were downregulated were associated with the ’ABC transporters’ and ‘plant hormone signal transduction’ pathways. Our data can provide new insights for evaluating the response mechanism of plants to selenium pollution and improving their resistance to selenium.