Identification of transcriptional factors of SvFT1 promoter, FT orthologue from Dwart Bamboo (Sasa veitchii var. tyugokensis) to open clear window for molecular control of mast flowering.





Bamboo species are widespread among East and Southeast Asia, the Indian subcontinent and South America with 1200-1500 species known while they are of a great cultural and economic importance for indigenous resident (Wong, 2004; Hirota and Nakanishi, 2009). Bamboo’s lifespan has been known to be that long with they spent most on vegetative growth. They have distinguishing reproductive traits, mast flowering, that they flower gregariously and synchronously at long interval. Many explored reasonable accounts for mast flowering in bamboo though the molecular regulation of mast flowering have remained to be unveiled (Janzen, 1976; Keeley and Bond, 1999; Franklin, 2004). On the other hand, recent studies about the one in Arabidopsis and rice are advanced (Putterill et al., 2004; Kobayashi and Weigel, 2007). FT, product of which is known to be flowering promoter, Florigen, seems to be well-preserved gene among seed plants while Hd3a in rice is FT ortholgue (Nishimura, 2008). As for its role of flowering, different pathways such as day-length, temperature and autonomous pathways are integrated with FT or FT orthologue indicating its great importance as a flowering promoter. SvFT1, FT orthologue from Dwarf Bamboo (Sasa veitchii var. tyugokensis) has been reveald while the rice transgenic with SvFT1 showed early flowering or even dwarfing (Honda, 2010). Meanwhile, the occurrence of SvFT1 is not clear. This study tries to identify the transcriptional factors of SvFT1 utilising SvFT1 promoter that is transferred to Nipponbare, experimental rice variety. Then, the theory for mast flowering will be developed in the light of molecular biology