Yi Wei, Jianhua Dai, Yanru Fan, Hengfu Yin, Jun Liu, Xiaojiao Han
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引用次数: 0
Abstract
Background
Toona sinensis and Toona ciliata both belong to the same genus in the Meliaceae family; however, the nitrate and nitrite contents in T. sinensis are significantly higher than those in T. ciliata. Given the growing emphasis on dietary health, it has become imperative to implement breeding strategies to reduce the excessive nitrite levels in T. sinensis. Nitrate reductase (NR) and nitrite reductase (NiR) are crucial enzymes in plant nitrogen metabolism. In this study, we employed a comparative analysis of the NR and NiR gene families in T. sinensis and T. ciliata. By integrating bioinformatics and expression pattern assessments, we aimed to elucidate the underlying factors contributing to the variance in nitrate and nitrite levels between these two species.
Results
T. sinensis exhibited higher nitrate and nitrite contents than T. ciliata. Through comprehensive genome-wide analysis, we identified two TsNRs and two TsNiRs in T. sinensis, compared to one TcNiR and two TcNiRs in T. ciliata, suggesting an expansion of NR members in T. sinensis relative to T. ciliata. The NR and NiR proteins in T. sinensis and T. ciliata share high sequence similarity and exhibit close genetic relationships with their counterparts in Populus trichocarpa and Salix purpurea. The exon–intron structures and conserved motifs of these genes were stringently conserved throughout evolutionary history. All the seven NR and NiR genes in both T. sinensis and T. ciliata harbor various cis-regulatory elements within their promoter sequences, which are associated with development, stress response, and hormonal regulation. Furthermore, the expression of TsNiR and TcNiR genes was also found to be tissue-specific. Among them, TcNR1 and TsNR2 exhibited the highest expression observed in mature leaves. Especially, the expression level of TsNR2 in mature leaves was 400-fold higher than in other tissues. In addition, transient overexpression of TsNiR1 and TsNiR2 in T. sinensis significantly reduced nitrite content.
Conclusions
The higher nitrite accumulation in T. sinensis compared to T. ciliata is attributed to its lower nitrite reductase activity, the expansion of the NR gene family, and the elevated expression of TsNR2 in the leaves.
期刊介绍：
Chemical and Biological Technologies in Agriculture is an international, interdisciplinary, peer-reviewed forum for the advancement and application to all fields of agriculture of modern chemical, biochemical and molecular technologies. The scope of this journal includes chemical and biochemical processes aimed to increase sustainable agricultural and food production, the evaluation of quality and origin of raw primary products and their transformation into foods and chemicals, as well as environmental monitoring and remediation. Of special interest are the effects of chemical and biochemical technologies, also at the nano and supramolecular scale, on the relationships between soil, plants, microorganisms and their environment, with the help of modern bioinformatics. Another special focus is the use of modern bioorganic and biological chemistry to develop new technologies for plant nutrition and bio-stimulation, advancement of biorefineries from biomasses, safe and traceable food products, carbon storage in soil and plants and restoration of contaminated soils to agriculture.
This journal presents the first opportunity to bring together researchers from a wide number of disciplines within the agricultural chemical and biological sciences, from both industry and academia. The principle aim of Chemical and Biological Technologies in Agriculture is to allow the exchange of the most advanced chemical and biochemical knowledge to develop technologies which address one of the most pressing challenges of our times - sustaining a growing world population.
Chemical and Biological Technologies in Agriculture publishes original research articles, short letters and invited reviews. Articles from scientists in industry, academia as well as private research institutes, non-governmental and environmental organizations are encouraged.
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