Enhancement Of Vitamin E Content In Wheat By Over-expressing γ-TMT Gene And Identification Of Wheat DREB Transcription Factor Family

Wheat is an important food crop in the world today,providing essential nutrients for human life.In this study,wheat was taken as the research object,and research was conducted in two directions: quality breeding and wheat abiotic stress resistance gene selection.First,genetic engineering methods were used to increase the content of vitamin E in wheat and change the composition of vitamin E in wheat,so as to increase the activity of vitamin E in wheat,and provide new ideas for wheat quality breeding.Second,Genome-Wide Identification of wheat DREB transcription factor family was conducted based on bioinformatics method,and the gene and protein characteristics of DREB family members was investigated in order to provide important clues for the discovery and utilization of heat-resistant genes in wheat.The main resμlts obtained in this study are as follows:1、The γ-TMT gene product can convert gamma tocopherol in plants to alpha tocopherols,which has higher biological activity.In this study,we cloned the γ-TMT gene from the wheat cμ ltivar KN199 and constructed an overexpression vector(pUbi-TMT)driven by the maize-derived Ubi promoter.The maize-derived Ubi promoter can start the transcription of genes in any tissue of a plant.The calli of immature embryos of wheat were transformed by the method of particle bombardment and induced to differentiate into complete wheat plants through tissue cμlture.The PCR method was used to identify the transgenic wheat.The resμlts showed that among the 22 transformed seedlings that were normally grown,there were 13 positive transgenic seedlings.The conversion rate is 59%.2、The DREB transcription factors is one of the most important gene families in plants,which plays the vital role in regμlating plant growth and development as well as response to diverse stresses.Although DREBs have been thoroughly characterized in many plant species,little is known about this family in the Triticum aestivum,especially those involved in the regμlatory network of stress processes.In this study,a comprehensive genome-wide search was performed to identify DREB gene family in Triticum aestivum and a total of 204 TaDREBs were obtained.Phylogenetic analysis classified them into six subgroups.Chromosomallocalization,gene structure and conserved protein motif as well as gene duplication events analysis were further performed to systematically investigate the evolutionary features of these TaDREB genes.Furthermore,the reg μ latory network between TaDREB and other genes were constructed using the orthology-based method,and 13 TaDREBs were found to be involved in the reg μ latory network and 179 network branches were identified.The expression profiles of TaDREB in different tissues and under diverse stresses were investigated using the available RNA-seq data and 11 tissue-specific and several stress-responsive TaDREB genes were identified.Finally,5 TaDREB genes were selected to validate their expressions under heat stress treatments using qPCR method and res μ lts verified that these TaDREBs coμld response to heat stress.