Cloning And Functional Analysis Of SVP Gene In Longan (Dimocarpus Longan Lour.)

’Sijimi’(S) and’Lidongben’(L) Longan (Dimocarpus longan Lour.) samples of grafting newly-sprouting shoots before maturity and the vegetative buds of’Honghezi’(H) were collected as materials for this experiment. Study the difference of SVP homologous genes in longan varieties, including the alternative splicing of sequence and differences of gene express b n. Explorate the role of SVP homologous genes in longan seasonal flowering regulation network,including flower bud differentiation and juvenile period regulation. The main results were as follows:the differential expression of 13 related genes in longan seasonal flowering regulation network were detected by RT-PCR, the results reflected that GI and FKF1 gene had a up-regulated expression in the S sample,but FLC,SVP,EMF2 showed a decrease in transcript abundance in the S sample. Two TFL1 homologous genes were found in longan, the expression of Unigene 6027 was slightly up-regulated in the S sample, but the expression of Unigene 6475 was down-regulated. The expression of LFY, API and SOC1 did not show significantly differential between the two samples.Collecting terminal tips of newly-sprouting shoots of’Sijimi’and leaf bud of ’Honghezi’ as material,the SVP homologous genes were cloned,seven alternative splicing sequence of gene SVP2719 and seven copys of gene SVP645 in’Sijimi’ were achieved,four alternative splicing sequence of gene SVP2719 and seven copys of gene SVP645 in’Honghezi’ were gained. Analysing the results,the majority of SVP645 homologous gene sequences had a difference between S and H,but SVP2719 gene had no difference in the two sample. The coding region of SVP2719 gene amino acid sequence in S and H were complete.The differential expression of SVP homologous genes of’Honghezi’ longan during flower bud differentiation.Were analysed by RT-PCR When the bud started flower differentiation in Jan.,the expression of SVP645 reached its peak, however, the expression of SVP2719 began to go down, this may indicate SVP645 and SVP2719 have a different function,and SVP2719 may suppress longan blooming..The SVP2719 gene sequence S-1 and S-6 were selected and constructed recombinant plasmid, Agrobacterium tumefaciens mediated transformated tobacco.The results showed that the SVP2719-SI gene could affect the shape of flower bud,and it couldn’t blooming.S VP2719-S6 gene could affect the shape of flower,but the number of petals, sepals, pistil and stamens had no variation..