Bioinformatics Analysis Of Histone And DNA Methylation Modification Gene Families In Wheat Crops And Their Responses To Abiotic Stress

Wheat and barley are two cereal crops belonging to the grass family.Wheat is the main source of nutrition for about 40 percent of the world’s population,and barley,which is mainly used for animal feed and brewing,is also considered a staple food.But their production growth has been fairly modest or stagnant over the past 20 years.Various abiotic stresses(such as low temperature,high temperature,drought,salt,flooding,etc.)are important factors affecting its yield.Therefore,improving the stress resistance of barley and wheat is very important for agriculture.In addition to elucidating the signal transduction mechanisms behind abiotic stress responses,more and more studies have shown that epigenetic mechanisms play an important role in plant responses to abiotic stress.The epigenetic code,mainly including DNA methylation,histone modifications,histone variants and some non-coding RNAs(nc RNAs),affects the structure and accessibility of chromatin,thereby affecting the biological function of chromatin.Histone and DNA methylation are reversibly regulated by HMT,HDM and C5-MTase,d MTase family proteins,respectively.At present,there are few studies on HMT,HDM,C5-MTase and d MTase families in the abiotic stress of barley and wheat.In this study,the origin and evolutionary relationship among species of HMT,HDM,C5-MTase and d MTase families were analyzed by means of bioinformatics,as well as their characteristics in barley and wheat and their expression patterns under abiotic stress.The main results are as follows:1.HMT and HDM may originate from Chromophytes,C5-MTase may originate from Chlorella,and d MTase may originate from Strexella.The evolution from algae to land plants was accompanied by dramatic changes in the environment.At the same time,the number of HMT,HDM,C5-MTase and d MTase family members increased significantly,and the gene sequence also changed significantly.At the same time,the expansion of the family led to the emergence of some new subfamilies and groups in HMT,HDM,C5-MTase and d MTase,which made histone and DNA methylation complex and diverse.Plant colonization of terrestrial habitats is accompanied by many abiotic stress factors,such as: high irradiance,lack of mineral nutrients(bare rocks,no soil),temperature changes,and dehydration.This gradually complicated DNA and histone methylation modification mechanism is more conducive to plants adapting to the complex land environment.2.The genetic similarity and synteny analysis between wheat crops and other angiosperms showed that HMT,HDM,C5-MTase and d MTase family members were highly homologous and conserved among wheat crops.The homology of protein sequences of each family among wheat crops is more than 90%,and the collinearity among wheat crops is much higher than that of other species,and they are subject to strong purification selection during the evolution of species.3.The HMT,HDM,C5-MTase and d MTase families are highly conserved among different germplasms,but artificial domestication also causes a small amount of differences among different germplasms.Then,the conserved domain,chromosomal location,and intraspecific collinearity were analyzed by bioinformatics methods.4.The cis-acting elements in the promoter region are always related to its transcription control and function.In this study,the predicted promoters of members of barley and wheat HMT,HDM,C5-MTase and d MTase were found to be related to light response,hormone Sensitive,tissue-specific,stress response-related functional elements.The expression profiles of each family gene at different tissue stages indicate that it may be involved in multiple growth and development processes of barley and wheat,while the transcriptome data and q RT-PCR results under various stresses indicate that it generally responds to various stresses in barley and wheat.