Fukudome M, Uchiumi T . Regulation of nitric oxide by phytoglobins in Lotus japonicus is involved in mycorrhizal symbiosis with Rhizophagus irregularis. . Plant science : an internatio2024 · 担当区分： 筆頭著者, 責任著者 記述言語： 英語 掲載種別： 研究論文（学術雑誌） 出版者・発行元： Plant Science Various reactive molecular species are generated in plant–microbe interactions, and these species participate in defense and symbiotic responses. Leguminous plants successfully establish symbiosis by maintaining an appropriate level of nitric oxide (NO), which is generated in the roots and nodules during root nodule symbiosis. Phytoglobin (plant hemoglobin) controls NO levels in plants. In this study, we investigated mycorrhizal symbiosis, which occurs in more than 80% of land plants, between Rhizophagus irregularis and Lotus japonicus to clarify the involvement of phytoglobin-mediated NO regulation. The mycorrhizae of L. japonicus exhibited higher NO levels in the presence of R. irregularis than in its absence, especially at the infection site. LjGlb1–1, a phytoglobin that regulates NO level in L. japonicus, was upregulated during symbiosis with R. irregularis. In transformed hairy roots carrying the ProLjGlb1–1:GUS construct, LjGlb1–1 expression was observed at the R. irregularis infection site. We further examined the symbiotic phenotypes of L. japonicus lines with high and low LjGlb1–1 expression with R. irregularis. During mycorrhizal symbiosis, the high LjGlb1–1 expression line exhibited better growth than the wild-type, whereas the low expression line exhibited poor growth. In addition, the expression of LjPT4, a phosphate transporter specific to mycorrhizal symbiosis, was higher in the high LjGlb1–1 expression line, whereas that of the tubulin gene of R. irregularis was lower in the low LjGlb1–1 expression line than in the wild-type. These results confirm that NO regulation by LjGlb1–1 is involved in mycorrhizal symbiosis in L. japonicus, as it is reportedly in nitrogen-fixing symbiosis. DOI： 10.1016/j.plantsci.2024.111984 Scopus PubMed
Mitsutaka Fukudome, Hazuki Shimada, Nahoko Uchi, Ken-ichi Osuki, Haruka Ishizaki, Ei-ichi Murakami, Masayoshi Kawaguchi, Toshiki Uchium . Reactive Sulfur Species Interact with Other Sig2014 · 担当区分： 筆頭著者 記述言語： 英語 掲載種別： 研究論文（学術雑誌） Reactive sulfur species (RSS) function as strong antioxidants and are involved in various biological responses in animals and bacteria. Few studies; however, have examined RSS in plants. In the present study, we clarified that RSS are involved in root nodule symbiosis in the model legume Lotus japonicus. Polysulfides, a type of RSS, were detected in the roots by using a sulfane sulfur-specific fluorescent probe, SSP4. Supplying the sulfane sulfur donor Na2S3 to the roots increased the amounts of both polysulfides and hydrogen sulfide (H2S) in the roots and simultaneously decreased the amounts of nitric oxide (NO) and reactive oxygen species (ROS). RSS were also detected in infection threads in the root hairs and in infected cells of nodules. Supplying the sulfane sulfur donor significantly increased the numbers of infection threads and nodules. When nodules were immersed in the sulfane sulfur donor, their nitrogenase activity was significantly reduced, without significant changes in the amounts of NO, ROS, and H2S. These results suggest that polysulfides interact with signal molecules such as NO, ROS, and H2S in root nodule symbiosis in L. japonicus. SSP4 and Na2S3 are useful tools for study of RSS in plants. DOI： https://doi.org/10.3390/antiox9020145
Teerana Greetatorn, Shun Hashimoto, Taro Maeda, Mitsutaka Fukudome, Pongdet Piromyou, Kamonluck Teamtisong, Panlada Tittabutr, Nantakorn Boonkerd, Masayoshi Kawaguchi, Toshiki Uchiumi, Neung Teaumroon2004 · 記述言語： 英語 掲載種別： 研究論文（学術雑誌） Bradyrhizobium sp. strain SUTN9-2 is a symbiotic and endophytic diazotrophic bacterium found in legume and rice plants and has the potential to promote growth. The present results revealed that SUTN9-2 underwent cell enlargement, increased its DNA content, and efficiently performed nitrogen fixation in response to rice extract. Some factors in rice extract induced the expression of cell cycle and nitrogen fixation genes. According to differentially expressed genes (DEGs) from the transcriptomic analysis, SUTN9-2 was affected by rice extract and the deletion of the bclA gene. The up-regulated DEGs encoding a class of oxidoreductases, which act with oxygen atoms and may have a role in controlling oxygen at an appropriate level for nitrogenase activity, followed by GroESL chaperonins are required for the function of nitrogenase. These results indicate that following its exposure to rice extract, nitrogen fixation by SUTN9-2 is induced by the collective effects of GroESL and oxidoreductases. The expression of the sensitivity to antimicrobial peptides transporter (sapDF) was also up-regulated, resulting in cell differentiation, even when bclA (sapDF) was mutated. This result implies similarities in the production of defensin-like antimicrobial peptides (DEFs) by rice and nodule-specific cysteine-rich (NCR) peptides in legume plants, which affect bacterial cell differentiation. DOI： https://doi.org/10.1264/jsme2.me20049
