Overexpression of paralogues of the wheat expansin gene TaEXPA8 improves low‐temperature tolerance in Arabidopsis

Yin

et al. 2020

BMC Plant Biol

Background Agricultural yield is closely associated with nitrogen application. Thus, reducing the application of nitrogen without affecting agricultural production remains a challenging task. To understand the metabolic, physiological, and morphological response of wheat (Triticum aestivum) to nitrogen deficiency, it is crucial to identify the genes involved in the activated signaling pathways. Results We conducted a hydroponic experiment using a complete nutrient solution (N1) and a nutrient solution without nitrogen (N0). Wheat plants under nitrogen-deficient conditions (NDC) showed decreased crop height, leaf area, root volume, photosynthetic rate, crop weight, and increased root length, root surface area, root/shoot ratio. It indicates that nitrogen deficiency altered the phenotype of wheat plants. Furthermore, we performed a comprehensive analysis of the phenotype, transcriptome, GO pathways, and KEGG pathways of DEGs identified in wheat grown under NDC. It showed up-regulation of Exp (24), and Nrt (9) gene family members, which increased the nitrogen absorption and down-regulation of Pet (3), Psb (8), Nar (3), and Nir (1) gene family members hampered photosynthesis and nitrogen metabolism. Conclusions We identified 48 candidate genes that were involved in improved photosynthesis and nitrogen metabolism in wheat plants grown under NDC. These genes may serve as molecular markers for genetic breeding of crops.

Section: Discussionmentioning

confidence: 99%

Transcription strategies related to photosynthesis and nitrogen metabolism of wheat in response to nitrogen deficiency

Yin

et al. 2020

BMC Plant Biol

“…In addition, wheat TaEXPA8A , TaEXPA8B , and TaEXPA8D responded to cold and drought stresses. The TaEXPA8B and TaEXPA8D transgenic plants showed stronger tolerance to cold stress, increased the activities of SOD, POD, and CAT, and improved the contents of soluble protein, MDA, and proline [36]. The analysis of cis-acting elements in the promoter regions of AnEXPA1 and AnEXPA2 genes revealed elements related to abiotic stress and hormone responses, such as CBF/DREB1, GA, and ABA (Table S2).…”

Section: Discussionmentioning

confidence: 99%

Expression of Two α-Type Expansins from Ammopiptanthus nanus in Arabidopsis thaliana Enhance Tolerance to Cold and Drought Stresses

Zhang

Hao

et al. 2019

IJMS

Expansins, cell-wall loosening proteins, play an important role in plant growth and development and abiotic stress tolerance. Ammopiptanthus nanus (A. nanus) is an important plant to study to understand stress resistance in forestry. In our previous study, two α-type expansins from A. nanus were cloned and named AnEXPA1 and AnEXPA2. In this study, we found that they responded to different abiotic stress and hormone signals. It suggests that they may play different roles in response to abiotic stress. Their promoters show some of the same element responses to abiotic stress and hormones, but some special elements were identified between the expansins that could be essential for their expression. In order to further testify the reliability of the above results, we conducted an analysis of β-glucuronidase (GUS) dyeing. The analysis showed that AnEXPA1 was only induced by cold stress, whereas AnEXPA2 responded to hormone induction. AnEXPA1 and AnEXPA2 transgenic Arabidopsis plants showed better tolerance to cold and drought stresses. Moreover, the ability to scavenge reactive oxygen species (ROS) was significantly improved in the transgenic plants, and expansin activity was enhanced. These results suggested that AnEXPA1 and AnEXPA2 play an important role in the response to abiotic stress. Our research contributes to a better understanding of the regulatory network of expansins and may benefit agricultural production.

“…10c), expansin gene family can increase the extensibility of cell wall [41][42][43]. Previous studies have shown that overexpression of expansin family members can cause the changes in crop morphology and improve the crop adaptability of stress resistance or low nutrition conditions [44,45]. For example, the up-regulated of the TaEXPB23 changed root system architecture of transgenic tobacco so as to improve the low phosphorus adaptability [8].…”

Section: Discussionmentioning

confidence: 99%

Transcription strategies related to photosynthesis and nitrogen metabolism of wheat in response to nitrogen deficiency

Yin

et al. 2020

Preprint

Background: It is a great challenge to reduce nitrogen application without yield reduction in agricultural production. Screening response gene related to important pathways will be helpful to understand the physiology, metabolism, and morphology response of wheat (Triticum aestivum) under nitrogen deficiency condition. Results: We conducted a hydroponic experiment with two nitrogen levels, which were complete nutrient solution (N1) and nutrient solution without nitrogen (N0). The results showed that the wheat phenotype were greatly changed under nitrogen deficiency, e.g., the decreased crop height, leaf area, root volume, photosynthetic rate, crop weight, and the increased root length, root surface area and root/shoot ratio. After a comprehensive analysis of the phenotype, transcriptome, GO pathways and KEGG pathways of wheat under nitrogen deficiency, we found that, the up-regulated Exp (24 genes) and Nrt (9 genes) families members were the positive response related to the increase of nitrogen absorption; the down-regulated Pet (3 genes), Psb (8 genes), Nar (3 genes) and Nir (1 genes) were related to the limitation of photosynthesis and nitrogen metabolism. Conclusions: This study provides 48 reference genes for improving photosynthesis and nitrogen metabolism of wheat under nitrogen deficiency, which can provide molecular markers for gene editing breeding.