Construction Of BAC Library Of Tartary Buckwheat And Analysis Of The BAC End Sequences

To further study tartary buckwheat(Fagopyrum tataricum Gartn.) genome and screen functional genes and help for whole genome sequencing of the tartary buckwheat,in this research, the tartary buckwheat variety JINQIAOMAI No.2(Fagopyrum tataricum Gartn.) native to Shanxi, China was used for BAC library construction. Then ends of some BAC clones were sequenced and. The expression of some genes in different tartary buckwheat tissues were investigated by qPCR. The main results are as follows:(1)The high molecular weight DNA(HMW-DNA) was isolated from tartary buckwheat leaves used the methods of Peterson ect. The library consisted of 30,000 clones with an average insert size of about 123 kb and the empty clone ratio was less than 1%. The library represented an equivalent about 6.9fold size of tartary buckwheat genome.(2)Then 48 BAC clones were randomly selected and sequenced BAC-end sequences. We obtained 89 BAC-end sequences, among which 7(8%) sequences had alignment results when comparing with NCBI GenBank database. The blast hits contain some genes with known function, such as rpoTm2 gene, Trrap gene and MDR1 gene and so on. Those genes are associated with DNA binding, transmembrane transport and phosphotransferase activity function. Meanwhile, we also found that the sequence of 40G19-F was probably repetitive sequences in the tartary buckwheat genome. Analysis of full-length sequence of 3 BAC clones, finding the blast hits contain some genes including regulation of growth and developmentof the plants, seed development, proline synthesis(homeobox,RIE1andTPRP-F1 gene respectively).(3)The expression levels of homeobox, RIE1 and TPRP-F1 were analyzed in different tartary buckwheat tissues using Real-Time PCR technology.The result showed the relative expression levels of homeobox gene in leaves was the highest, followed by flower. By contrast, expression levels of homeobox gene in root was the lowest. Speculated that homeobox may be associated with the development of buckwheat leaves and flowers.RIE1 gene was highly expressed at different tartary buckwheat tissues,which the highest expressed in theleaves.The expression of TPRP-F1 differs in different tartary buckwheat tissues.Relative expression levels of TPRP-F1 in leaves was the highest.