Genetic Analysis Of Brachypodium Distachyon From Israel And Bioinformatics Analysis Of Dehydrin Protein Family Of B. Distachyon

Brachypodium distachyon also known as the Second Flower glandulifera, belongs to Poa grass subfamily are mainly distributed in South Europe, North Africa, Southwest Asia and other places. Based mostly diploid, the genome size is about 300Mb. B. distachyon have a close genetic relationship with temperate cereal crops. B. distachyon has some advantages that the model plant of grass species-rice does not have, for example many physiological structures of rice are different with rainfed cereal crops such as barley, wheat, maize, millet. But B. distachyon does not exist this obstacle, so it is a new temperate grass model plant. Such as drought, cold and salinity are the mainly factors affecting plant growth and development. Stimulated by environment stress, plants can express a variety of proteins for adaptation. Dehyrin is a very important type of these protection protein. As a new model plant, it is very important to in-depth study of molecular mechanism of stress resistance of B. distachyon.(1) To investigate the genetic diversity among B. distachyon 29 accessions from Israel and 7 accessions from other areas, PCR with intron-splice junction primer was employed for this study. The results indicated that 145 distinct PCR bands in total were amplified using 8 primers and 10 primer combinations, and 93 (64.58%) of them were polymorphic. A systematic cluster analysis conducted with UPGMA shows that 36 B. distachyon accessions can be classified into 3 groups: the first group being diploid accession, the second group being hexaploid not from Israel, the third group being a natural population from Israel, and this population was clustered into two different ecotype groups. Results obtained from the principal component analysis (PCA) were consistent with those from the cluster analysis. This study provided a theoretical foundation for origin and evolution of Israeli B. distachyon, collection and identification of genetic resourse of this plant.(2) Using Hidden Markov Model scan strategy in Pfam database, Dehydrin protein profiles were obtained, then doing Blastp search in B. 8X release proteins database. Ten protein that have YSK structures was accessed, Bradi1g37410, Bradi4g22290, Bradi3g43870, Bradi4g22280, Bradi2g47580, Bradi5g10860, Bradi3g51200, Bradi1g13330, Bradi4g19525 and Bradi3g43855. Using bioinformatics analysis software CLUSTALX, Mega4.0, NNPP, TFSEARCH, ProtScale and Protparam, sequence analysis and structure prediction were conducted. The results show that physical and chemical properties among these ten member of B. distachyon dehydrin exsit some differences. B. distachyon dehydrin protein have loose structures and typical features of YSK structures, strong hydrophilic, no signal peptide, and some members are peripheral proteins, some are membrane proteins, promoter upstream also have ABRE, DRE, MYB, MYC cis-acting elements. Above results provide a theoretical basis for the further studying of biochemical characteristics, molecular evolution, functional verification of B. distachyon dehydrin proteins and Mechanism of resistance to environmental stress of B. distachyon.