Abstract
To investigate the flowering mechanism in boreal forest trees, we have isolated genes homologous to Arabidopsis flowering genes LEAFY, LGY1 and LGY2, from Larix gmelinii var. japonica, a dominant species in the boreal forest. The expression of both genes was higher in buds, which become floral primordia, than in male and female flowers. The LGY1 expression in the buds increased from May and decreased in September, while the LGY2 expression was constant. The expression of the Arabidopsis AGAMOUS-like gene isolated initiated from July, indicating that LGY1 is expression prior to the initiation of floral organ development. These results suggest that LGY1 is involved in the floral determination. We have been constructing the transgenic Arabidopsis plants harboring LGY1 or LGY2 driven by the cauliflower mosaic virus 35S promoter. We will present the results from the transgenic plants and discuss about possible functions of LGY1 and LGY2.
