IntroductionSaline-alkali soils are a major constraint to mung bean cultivation and extension, and prohexadione-calcium (Pro-Ca) can enhance plant tolerance to saline-alkali stress.MethodsIn order to explore the regulatory effect and mechanism of Pro-Ca on mung bean growth under saline-alkali stress, the morphology, ultrastructure, physiological indicators, and gene expression were measured in this study.ResultsThe results indicate that Pro-Ca can improve the adaptability of mung bean to saline-alkali stress. Specifically, it manifests as increasing dry matter accumulation, protecting the structural integrity and quantity of organelles such as chloroplasts and mitochondria, enhancing photosynthetic capacity, increasing antioxidant enzyme activity and the content of osmoregulatory substances. These changes may be related to the enhanced expression of calcium signal transmission and the synthesis of nitric oxide (NO), polyamines and jasmonic acid in the root system under saline-alkali stress.DiscussionOur findings partially explain the physiological and molecular mechanisms by which Pro-Ca enhances the tolerance and adaptability of mung bean plants to saline-alkali stress. This may become an effective strategy for the utilization of saline-alkali soil.

SUMOylation is an important posttranslational modification of eukaryotes that is widely present in metabolic regulation processes under various stresses. SIZ1 is a SUMO E3 ligase that plays a key role in substrate-specific recognition and directly promotes the binding of SUMO proteins to target proteins. Here, we reviewed the characteristics of SUMO as well as SUMOylation and the role of the SUMO E3 ligase SIZ1 in plant adaptation to abiotic stresses such as abnormal temperature, drought, salinization, phosphorus and nitrogen deficiency, heavy metal and metalloid toxicity, light exposure and reactive oxygen species. This review will enhance our understanding of these stressors and provide a useful reference for appropriate crop improvement, especially in suboptimal environments. Moreover, we provide a reference for future research on the role of SUMOylation in plant responses to abiotic stress.

As two coexisting abiotic stresses, salt stress and alkali stress have severely restricted the development of global agriculture. Clarifying the plant resistance mechanism and determining how to improve plant tolerance to salt stress and alkali stress have been popular research topics. At present, most related studies have focused mainly on salt stress, and salt-alkali mixed stress studies are relatively scarce. However, in nature, high concentrations of salt and high pH often occur simultaneously, and their synergistic effects can be more harmful to plant growth and development than the effects of either stress alone. Therefore, it is of great practical importance for the sustainable development of agriculture to study plant resistance mechanisms under saline-alkali mixed stress, screen new saline-alkali stress tolerance genes, and explore new plant salt-alkali tolerance strategies. Herein, we summarized how plants actively respond to saline-alkali stress through morphological adaptation, physiological adaptation and molecular regulation.

利用大豆基因组数据库Phytozome v12.1.6获得大豆DNA脱甲基化相关基因Glyma03g34860和Glyma10g07601的CDS序列,以大豆叶片RNA为模板,RT-PCR克隆获得Glyma03g34860基因大小为5226 bp,Gly-ma10g07601基因大小为6045 bp.利用STRING在线软件预测这两个转录本的互作蛋白质完全一致,主要互作蛋白8个,包括一个AP位点裂解酶和2个RNA聚合酶亚基;采用qRT-PCR分析他们对大豆连作综合逆境胁迫的响应.结果表明:连作综合逆境胁迫使Glyma03g34860和Glyma10g07601的表达均不同程度上调,其中,Glyma10g07601基因在大豆品种安达农家、黑大豆、绥农14和黑农40达显著水平(P<0.05),分别增加1.37、1.22、1.98倍和1.67倍;Glyma03g34860基因在大豆品种垦丰16、绥农14达显著水平(P<0.05),分别增加1.62倍和1.65倍,因此推测他们可能通过使基因组DNA脱甲基化而参与大豆连作综合逆境胁迫的响应.

Alternative splicing is a common but complex posttranscriptional regulatory process in eukaryotes, through which multiple different transcripts are produced from a single pre-mRNA. An increasing number of studies have revealed that alternative splicing is widespread in fungi. Intron retention (IR) is considered the most prevalent splicing type due to the relatively short introns and long exons involved in this process. Alternative splicing is coordinated by a variety of factors, including genomic structure characteristics, TPP riboswitches, splicing factors and DNA methylation, and is involved in the regulation of growth and development, and the improvement of survivability and pathogenicity. Taken together, the results show that alternative splicing events are fungal evolutionary adaptations to changing external conditions.

稻瘟病菌是重要的模式致病真菌,该菌引发的稻瘟病也是全球水稻最严重的病害之一,因此对稻瘟病菌的研究具有重要的学术意义和实际价值.细胞周期受多层次、多因子共同调控,其相关控制蛋白在真菌的形态建成、发育分化、逆境适应及致病性等方面发挥重要作用.为明确稻瘟病菌细胞周期控制蛋白的生物信息学特性,利用多种生物信息学软件和网站对获得的3种细胞周期控制蛋白Cwf19、Cwf16和Cwf14的理化性质、亚细胞定位、分子进化、翻译后修饰、空间结构、互作蛋白等进行分析,探讨了其可能的作用机制,为进一步利用反向遗传学手段深入研究其生物学功能奠定基础.

BACKGROUND:Continuous cropping stress involves such factors as biological barriers, allelopathic autotoxicity, deterioration of soil physicochemical properties, and soil fertility imbalance and is regarded as a kind of comprehensive stress limiting soybean yield and quality. Genomic DNA methylation is an important regulatory mechanism for plants to resist various environmental stresses. Therefore, it is especially worthwhile to reveal genomic methylation characteristics under stress and clarify the relationship between DNA methylation status and continuous cropping stress adaptability in soybean.RESULTS:We generated a genome-wide map of cytosine methylation induced by this kind of comprehensive stress in a tolerant soybean variety (Kang Xian 2, KX2) and a sensitive variety (He Feng, HF55) using whole-genome bisulfite sequencing (WGBS) technology. The expression of DNA demethylase genes was detected using real-time quantitative PCR (qRT-PCR). The functions of differentially methylated genes (DMGs) involved in stress response in biochemical metabolism and genetic information transmission were further assessed based on Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The results showed that genomic DNA demethylation was closely related to continuous cropping comprehensive stress adaptability in soybean, which was further verified by the increasing expression of DNA demethylases ROS1 and DML. The demethylation of mCpG and mCpHpG (mCpApG preferred) contexts was more critical, which mainly occurred in gene-regulatory regions at the whole-chromosome scale. Moreover, this kind of stress adaptability may be related to various stress responders generated through strengthened glucose catabolism and amino acid and fatty acid anabolism, as well as fidelity transmission of genetic information.CONCLUSIONS:Genomic DNA demethylation was closely associated with continuous cropping comprehensive stress adaptability, highlighting the promising potential of screening continuous cropping-tolerant cultivars by DNA methylation index and further exploring the application of DNA demethylases in soybean breeding.