Phylogenetic Analysis Of En/Spm-like Transposons In The Bambusoideae And Construction Of MLE Transposon Tagging

Transposable elements(TEs),pieces of DNA sequence in the chromatin,are able to move from one locus to another in a process known as transposition.Transposable elements(TEs)are a major component of most eukaryotic genomes and are widely distributed in bambusoideae plants.In this research,we studied 2 kinds of transposable elements in the bambusoideae plants.The main results are summarized in the following.(1)We cloned En/Spm-like transposons ransposon transposase sequences in Phyllostachys heterocycla var.pubescens,Melocanna baccifera(Roxb.)Kurz,Bambusa multiplex(Lour.)and Phyllostachys heterocycla(Carr.)Mitford,all of which belong to bambusoideae and got 186 pieces of En/Spm-like transposon transposase sequences whose length ranged from 615 to 656 bp and whose similarity was 52.9%~100%.Therefore,we speculated En/Spm-like transposons are widely distributed in bambusoideae plants.Meanwhile,it was observed from clustering analysis that these 186 pieces fell into five groups,respectively named Ba_Enspm 1,Ba_Enspm2,Ba_Enspm3,Ba_Enspm4 and Ba_Enspm 5.(2)The analysis showed that En/Spm-like transposons of bambusoideae,with gene polymorphism,were affected by natural selection and their transposition activity was inhibited in the process of evolution.The evolution of the elements was realized mainly via the vertical transmission,with possibly existing horizontal transmission.(3)We successfully developed two pairs of MLE dual transposon taggings based on Phmar1 and Phmar2 and they were named E2/Mini3-1 and Xc/Mini S-1-20.There are several advantages of the MLE dual transposon tagging.First,it has GFP fluorescent protein reporter gene,beneficial for detection of transposition events.Second,plants containing MLE dual transposon tagging were obtained by means of cotransformation and hybridization,which is in favor of the manual regulation of the use of the MLE dual transposon tagging.