Study reveals the biological mechanism of nitrogen fixation in seabuckthorn actinomycetes

Recently, "New Phytologist" (New Phytologist) published online publications from the Center for Excellence in Molecular Plant Science, Chinese Academy of Sciences, the State Key Laboratory of Agricultural Genomics, Shenzhen BGI Institute of Life Sciences, Shanxi Jinzhong Forestry Research Institute, etc.
The research paper titled The genome of Hippophae rhamnoides provides insights into a conserved molecular mechanism in actinorhizal and rhizobial symbiosis is a collaborative research paper of the family unit
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This study assembled a chromosome-level reference genome of sea buckthorn to explore the biological mechanism of nitrogen fixation in Actinomyces sea buckthorn
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Some plants of Legumes, Rosoides, Cucurbits and Fagaceans can symbiotic nitrogen fixation with rhizobia or actinomycetes.
The molecular mechanism of symbiotic nitrogen fixation between legumes and rhizobia has been deeply studied
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At present, there is no good research model plant for symbiotic nitrogen fixation by actinomycetes, so there are few studies on the mechanism of symbiotic nitrogen fixation by actinomycetes, and the progress is slow
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Sea buckthorn is a deciduous shrub of the genus Sea buckthorn in the family Elaeaceae.
It is suitable for the barren areas of North China and Northwest China where water and fertilizer are scarce.
It is a hero for windbreak and sand fixation.
The most important thing is that its roots and actinomycetes symbiotically fix nitrogen; its fruits are rich in vitamin C and Active substances such as flavonoids are the raw material suppliers of healthy drinks and have important ecological and economic value
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The study used sea buckthorn collected from Shanxi as the material to assemble a chromosome-level reference genome to clarify the evolutionary relationship of the controversial nitrogen-fixing branch plants
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Seabuckthorn and its close relative, Dongzao, diverged about 70-80 million years ago; after the two parted ways, seabuckthorn experienced another unique whole-genome duplication event
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The research team analyzed the microbial diversity of sea buckthorn nodule samples, identified Actinomycete Frankia as the main source of root nodule symbiotic microorganisms, and sequenced the transcriptomes of sea buckthorn nodules and roots and other tissues.
Among the symbiosis-related genes of root nodule nitrogen fixation, it was found that most of the symbiosis-related genes showed orthologous relationship, such as NIN, RPG, NSP2, DMI2, etc.
, indicating the conservation of legume-rhizobia symbiosis and actinomycete nodule symbiosis
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The reference genome of sea buckthorn provides a scientific basis for studying the molecular biology of sea buckthorn, plant-actinomycete symbiosis and genetic improvement of sea buckthorn
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The study also used information such as the genome and transcriptome of sea buckthorn to identify genes related to the vitamin C synthesis pathway, and map the metabolic pathway of vitamin C synthesis in sea buckthorn
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The research was funded by the National Key R&D Program, the Chinese Academy of Sciences, and the National Natural Science Foundation of China
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Seabuckthorn root nodule slices Source: Center for Excellence and Innovation in Molecular Plant Science, Chinese Academy of Sciences