Cloning And Quantitative Expression Analysis Of Sbei Gene In Cassava And Construction Of RNAI Vector

In this research, the cassava variety of FX01 and SC124 are chosen as the test material. We use RT-PCR cloning technique cloned the cassava sbei from FX01 and SC124, and then we analyzed the sequence of sbei and constructed RNAi expression vector. We also studied the expression level of cassava sbei in different days and tissues and varieties. In order to know the relationship between starch branching enzyme activity and starch synthesis in the root of cassava, we analyzed the starch branching enzyme activity, total starch content and branched chain starch content, amylose content in the cassava root of the different growth period. The main results are as follows:1、The sequence analysis of sbei showed that the sequence of sbei from FX01 and SC124 have no difference and its encoding amino acids have no difference, the sequence of sbei contains the complete open reading frame of 2559 bp, encoding 852 amino acids.2、The q-PCR research showed that the expression quantity of sbei is higher in FX01 than in SC124. The expression quantity of sbei in root of cassava is higher than that of leaf and stem. At root enlargement, the expression quantity of sbei in leaf, stem, root of cassava is higher than other time.3、According to the sequence of sbei, select a 426 bp fragment of RNA interference, successful constructed RNAi expression vector PART27-RNAi,4、In the whole growth period, the activity of SBE in FX01 was higher than that in SC124. In the late of root formation, the SBE activity reached the highest in the root and the total starch increase fastest rate.5、The total starch content and amylopectin content are higher in FX01 than in SC124, but the amylose content is lower in FX01 than in SC124.