Abstract
Leghemoglobin (Lb) is produced abundantly in root nodule cells and has specific roles on symbiotic nitrogen fixation between rhizobia and leguminous plants. Lb promoter and GFP fusion gene was constructed to investigate Lb gene-expression in Lotus japonicus, and transformation of L. japonicus mediated by Agrobacterium rhizogenes was performed. Hairy roots were induced by infection of A. rhisogenes and transformation with the fusion gene was confirmed by PCR. The structure of root nodules formed by inoculation of Mesorhizobium loti on hairy root was normal. mRNA was extracted from nodules on hairy roots, and expression of the fusion gene was confirmed by RT-PCR. The nodulation process of the transformed hairy roots was observed by fluorescent microscope. At the early stage of nodulation, fluorescence supposed to be GFP origin was observed around the vascular system closed to the nodule primordia. This result suggests the possibility of Lb-expression in the out of symbiotic zone.
