Screening Of Some Matrix Attachment Regions In Rice And Preliminary Analysis

MAR/SAR(Matrix/Scaffold attachment region or Matrix/Scaffold association region)are essential and abundant regulatory DNA sequences in chromatin of eukaryotic cells that tightly associated with the nuclear matrix or scaffold in vitro.It was found that MAR could overcome transgene silcencing effectively.The function of MAR is unrelated to copies of foreign gene in transgenic.The classical isolation and purification method of MAR is many and miscellaneous with trifles and time-consuming.According to summarize the biochemical evidence for the modalities of MAR,we can screen MAR sequence from bioinformatics database with the Predicting Technique of MAR(PTM).Its speed up the screening of MAR sequence and reduce screening cost.In the study,we utilize the database of BGI,view the rice gene mapping of chromosomes.Select the seuquence between genes in the genes active area,and analysis the sequence with MAR-Wiz.Acoording to the MAR-Analysis Summary Report,we screen 10 candidate MAR sequences with high MAR-potential.Clone these candidate MAR sequences,choose gus as report gene,and link the candidate MAR sequence at both ends of gus gene to construct Expression Vector.Equipped with control,we construct 21 plant expression vectors in all.Then transform vector into wild type Oryza Sativa L through ATMT.Through detecting the gus expression level of 509 transgenic positive stains,we Initially identified 4 MAR sequences which can significantly improve the exogenous gene expression level.The 4 MAR sequences are numbered M2?M3?M6?and M7.M2 which is locate in chr07(06882521)can increase gus expression level by 4 times.M3 which is locate in chr07(21231402)can increase gus expression level by 18 times.M6 which is locate in chr08(25631056)can increase gus expression level by 1 time.M7 which is locate in chr09(20378264)can increase gus expression level by 1 time.