Screening And Analysis Of Seed Filling Period CDNA Library Of Tartary Buckwheat

With a well-balanced amino acids composition and bioactive flavonoids in the seeds,Tartary buckwheat(Fagopyrum tartaricum) is a typical minor crop used as both medicine andfood. The seed filling period is the crucial stage for accumulation of those components, so thestudy on the gene expression profile of this stage has significant value for the revealing themetabolism and regulation of functional components in tartary buckwheat seed.In our laboratory, a full-length cDNA phage library of the filling period seeds wasconstructed through the SMART (switching mechanism at5’ end of RNA transcript) technique.In this study we focus on the screening of this cDNA library. The result of PCR analysis of theinserted fragments after cyclization showed that the size ranged from400bp to1100bp withthe dominance of ESTs ranging from700bp to800bp. Part ESTs have been submitted to NCBIwith GenBank accession number:GO477569，GO496285~GO496321, JK729372~JK729381.Sequence alignment results demonstrated that numbers of ESTs with high, moderate, lowsimilarity are118,421,241, respectively, composing80.53%of the total. No similarsequences were found for the rest.Similar sequences found are genes of proteins includingdehydrin, defensin, chitinase, heat shock protein90, heat shock protein101, oleosin,11S seedstorage globulin,13S storage protein,phenylalanine ammonia-lyase(PAL), flavanone-3-hydroxylase(F3H) and so forth, PAL and F3H are involved in the synthesis of secondarymetabolites in tartary buckwheat. These results laid the foundation of the further research ofseed proteins and genes related to secondary metabolism.Moreover, genes discovered were divided into12catagories based on The EUArabidopsis Genome Project：involve in metabolism，energy, cell growth/differentiation,transcription, protein synthesis, storage protein, transport, cell structure, signal transduction,drought resistance/defense, secondary metabolism and others. A data bank systemProgrammmed by Visual Basic used to facilitate the retrieving of catagoried gene sequences.