Genome-wide identification and expression analysis of DNA demethylase family in cotton

Journal of Cotton Research

[Background] DNA methylation is an important epigenetic factor that maintains and regulates gene expression. The mode and level of DNA methylation depend on the roles of DNA methyltransferase and demethylase, while DNA demethylase plays a key role in the process of DNA demethylation. The results showed that the plant’s DNA demethylase all contained conserved DNA glycosidase domain. This study identified the cotton DNA demethylase gene family and analyzed it using bioinformatics methods to lay the foundation for further study of cotton demethylase gene function.

[Results] This study used genomic information from diploid Gossypium raimondii JGI (D), Gossypium arboreum L. CRI (A), Gossypium hirsutum L. JGI (AD1) and Gossypium barbadebse L. NAU (AD2) to Arabidopsis thaliana. Using DNA demethylase genes sequence of Arabidopsis as reference, 25 DNA demethylase genes were identified in cotton by BLAST analysis. There are 4 genes in the genome D, 5 genes in the genome A, 10 genes in the genome AD1, and 6 genes in the genome AD2. The gene structure and evolution were analyzed by bioinformatics, and the expression patterns of DNA demethylase gene family in Gossypium hirsutum L. were analyzed. From the phylogenetic tree analysis, the DNA demethylase gene family of cotton can be divided into four subfamilies: REPRESSOR of SILENCING 1 (ROS1), DEMETER (DME), DEMETER-LIKE 2 (DML2), and DEMETER-LIKE3 (DML3). The sequence similarity of DNA demethylase genes in the same species was higher, and the genetic relationship was also relatively close. Analysis of the gene structure revealed that the DNA demethylase gene family members of the four subfamilies varied greatly. Among them, the number of introns of ROS1 and DME subfamily was larger, and the gene structure was more complex. For the analysis of the conserved domain, it was known that the DNA demethylase family gene member has an endonuclease III (ENDO3c) domain.

[Conclusions] The genes of the DNA demethylase family are distributed differently in different cotton species, and the gene structure is very different. High expression of ROS1 genes in cotton were under abiotic stress. The expression levels of ROS1 genes were higher during the formation of cotton ovule. The transcription levels of ROS1 family genes were higher during cotton fiber development.

[Title]Genome-wide identification and expression analysis of DNA demethylase family in cotton

[Authors] YANG Xiaomin, LU Xuke, CHEN Xiugui, WANG Delong, WANG Junjuan, WANG Shuai, GUO Lixue, CHEN Chao, WANG Xiaoge, WANG Xinlei & YE Wuwei *

Journal of Cotton Research. 2019, 2: 16

https://doi.org/10.1186/s42397-019-0033-2

https://jcottonres.biomedcentral.com/articles/10.1186/s42397-019-0033-2

An isopentyl transferase gene driven by the senescence-inducible SAG12 promoter improves salinity stress tolerance in cotton

Journal of Cotton Research

[Background] Soil salinity seriously affects cotton growth, leading to the reduction of yield and fiber quality. Recently, genetic engineering has become an efficient tool to increase abiotic stress tolerance in crops.

[Results] In this study, isopentyl transferase (IPT), a key enzyme involved in cytokinin (CTK) biosynthesis from Agrobacterium tumefaciens, was selected to generate transgenic cotton via Agrobacterium-mediated transformation. A senescence-inducible SAG12promoter from Arabidopsis was fused with the IPT gene. Ectopic-expression of SAG12::IPT significantly promoted seed germination or seedling tolerance to salt stress. Two IPTtransgenic lines, OE3 as a tolerant line during seed germination, and OE8 as a tolerant line at seedling stage, were selected for further physiological analysis. The data showed that ectopic-expression of SAG12::IPT induced the accumulation of CTKs not only in leaves and roots, but also in germinating seeds. Moreover, ectopic-expressing IPT increased the activity of antioxidant enzymes, which was associated with the less reactive oxygen species (ROS) accumulation compared with control plants. Also, ectopic-expression of IPT produced higher K+/Na+ ratio in cotton shoot and root.

[Conclusions] The senescence-induced CTK accumulation in cotton seeds and seedlings positively regulates salt stress partially by elevating ROS scavenging capability.

[TitleAn isopentyl transferase gene driven by the senescence-inducible SAG12 promoter improves salinity stress tolerance in cotton

[Authors] SHAN Yi, ZHAO Peng, LIU Zhao, LI Fangjun* & TIAN Xiaoli

Journal of Cotton Research. 2019, 2: 15

https://doi.org/10.1186/s42397-019-0032-3

https://jcottonres.biomedcentral.com/articles/10.1186/s42397-019-0032-3

World Cotton Day

07 October 2019 has been announced as World Cotton Day by WTO. Cotton community will celebrate this day across the globe. The WTO Secretariat is organizing the event at WTO Headquarters Geneva in collaboration with the Secretariats of the United Nations Food and Agriculture Organization (FAO), the United Nations Conference on Trade and Development (UNCTAD), the International Trade Centre (ITC) and the International Cotton Advisory Committee (ICAC). This event stems from the Cotton-4’s official application for the recognition of a World Cotton Day by the United Nations General Assembly, reflecting the importance of cotton as a global commodity.

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