Isolation of nodulation genes of leguminous plants by trasposon tagging

1996 Fiscal Year Final Research Report Summary

• Project/Area Number: 06454135
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 生物資源科学
• Research Institution: The University of Tokyo
• Principal Investigator: OYAIZU Hiroshi Graduate School of Agriculture and Agricultural Life Sciences, The University of Tokyo, 大学院・農学生命科学研究科, 助教授 (70177301)
• Project Period (FY): 1994 – 1996
• Keywords: Nodulation / Leguminous plant / Nitrogen fixation / タギング

Research Abstract

We carried out the following experiments.
1) Transposon tagging
We tried to induce Ac and Ds into Lotus coroniculatus and Medicago trancatula. For L.cononiculatus we got one Ds induced plant, but did not get Ac induced one. For M.trancatula we could not determine suitable condition of Ac and Ds induction. Then, we are trying to introduce Ds and Ac into L.cononiculatus by the particle gun-method and direct electroporation-method.
2) Nodulation of some members of family Caesalpineae.
The members of family Caesalpineae usually are not nodulated in the field. However, some members such as Chamaecrista nomame are nodulated. To reveal the differences between nodulated and not-nodulated species will give useful information to create nitrogen fixing crops. We compared Chamaecrita nomame and Senna obtusifolia, which in not nodulated in the natural environments. Not-nodulating species apparently secreted much more flavonoid-like compounds from their seeds and roots. We found that Senna obtusifolia formed nodule-like structure when it was cultivated in the liquid medium. We analyzed flavonoid compositions secreted from roots of Senna obtusifolia and tried to clarify wheather bacterial inoculation induces some special flavonoids. From this experiment, the flavonoid composition was apparently changed in the nodulating plant but not in the not-nodulating plant.
3) Chemical synthesis of nod factor
Nod factor produced by rhizobia is a trigger molecule of nodulation. We developed a highly efficient chemical synthesis method of this molecule.