Research On The Expression Of Cell Cycle Genes Regulated By Flowering Related Genes

The flowering regulation has a great relationship to the accomplishment of flower transition and the genetic quality of progeny. Thus scientists pay more attention to deep the acknowledgements to the network of flowering regulation. Flower transition and development are the result of a series of cell division and differentiation, the study on cell cycle in the regulation of flowering is much helpful to complete the pathway of flowering regulation. Based on the analyses to the transcriptome of a later flowering tobacco, we found the relationship between cell cycle and plant life cycle. For exploring the affected cell cycle genes on flowering time and the relationship between cell cycle and flowering regulation, we did a deep research with the Rr MYB7 later flowering tobacco and many transgenic Arabidopsis with varied flowering time, it is suggested that there is tighly relationship between cell cycle genes and flowering regulation. The main results are as follows:1. The transgenic tobacco lines with a phenotype of drawf, retarded, smaller and curled leaves and delayed flowering were screened out with the selfed seeds of the transgenic tobacco of overexpression Rr MYB7. A similar phetotype were found between the transgenic tobacco and Arabidopsis via overexpression Rr MYB7 in Arabidopsis.2. The roots length were measured and it was found that the primary root was obviously shortened in 10-day Rr MYB7 transgenic tobacco compared with wide type tobacco.3. According to the transcriptome derived from RrMYB7 transgenic tobacco, we found many cell cycle genes were down regulated in the Rr MYB7 transgenic tobacco, so it was suggested that Rr MYB7 might have an impact on the expression of cell cycle genes in transgenic tobacco.4. Four overexpression vectors of the flowering time genes were constrcucted, p CAMBIA2300s-At FT, p CAMBIA2300s-At FD, p CAMBIA2300s-At AP1, p CAMBIA23 00s-At FT+At FD, and were transformed into Arabidopsis and then we got the transgenic plants.Transgenic plants harboring At FT, At AP1 have an earlier flowering time than the wild-type respectively and the latter one have a sepalody floral organ, only in the later stage of the development, a few seeds come into being.5. By expression analysis to the cell cycle genes in the Arabidopsis related flowering time, harboring ft-1, fd-1, tfl1-11, lfy-1 mutants and overexpression of At FT transgenic Arabidopsis, it’s found that the expression of Cyc A2;1, Cyc D3;1 and Cyc D3;3 had been down regulated only in lfy-1 mutant suggesting LFY might have an impact on the expression of cell cycle genes.