Abstract
We investigated the zinc accumulation pattern and mechanisms in Lotus japonicus. L. japonicus is a model legume for molecular biology and the resources for genetics are well established. From our previous work, zinc accumulation in seed was different between two cultivars Gifu and Miyakojima, therefore, objectives of this study were to identify the zinc accumulation pattern in vegetative stage between these two lines and to determine the loci governing zinc uptake and translocation by using recombinant inbred lines (RIL; Gifu x Miyakojima).
In 4-weeks-old plants, zinc concentration in Gifu was higher than that in Miyakojima in all investigated tissues and, by comparing Zn-65 distribution images, zinc uptake and translocation activities were also higher in Gifu. The zinc accumulation in shoot was investigated with Zn-65 and 80 RILs. Using maximum likelihood method, J/qtl program identified several major QTL. The genes located on these QTL were investigated based on the L. japonicus genome sequence and several genes annotated zinc transporter, which gene expression levels were higher in Gifu, were found. The relationship between these genes and zinc accumulation will be discussed.
