Recognizing Plant Physiology first authors: Sho Fujii

Sho Fujii, first author of Digalactosyldiacylglycerol is essential for organization of the membrane structure in etioplasts

Current Position: Ph.D. student, Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo

Education: Short-term Scholar, University of Michigan (2018); MS of Arts, The University of Tokyo (2016); BS of Liberal Arts, The University of Tokyo (2014)

Non-scientific Interests: Classical music, hiking, traveling, baking and eating

Brief bio: I started my carrier in 2013 at Prof. Hajime Wada’s lab in the University of Tokyo, Japan. I am continuing studying in the same lab, focusing on functions of membrane lipids in plastids. My study began with characterization of Arabidopsis transgenic lines that express artificial microRNAs in a dexamethasone-dependent manner to downregulate MGD1 encoding the major isoform of monogalactosyldiacylglycerol (MGDG) synthase. The results revealed that MGDG, the most abundant lipid in plastids, needs to be synthesized by MGD1 at the early stage of germination to develop chloroplasts and their precursors, etioplasts, and to establish photosynthetic capacity. Digalactosyldiacylglycerol (DGDG), another main lipid constituent of the chloroplast membrane, is also required for photosynthesis, but its function in etioplasts was unknown. In the present study, we characterized etiolated seedlings of a DGDG-deficient Arabidopsis mutant, dgd1, and showed that DGDG is indispensable for maintenance of prolamellar bodies, unique lattice membrane systems in etioplasts, and membrane-associated processes of the chlorophyll biosynthesis pathway. Our researches shed light on hidden roles of galactolipids in initiating processes of photosynthetic membrane biogenesis and chloroplast development. To move on to my next step, I’m now challenging to find out other unexpected functions of plastid lipids.