Graduate School of Frontier Sciences, The University of Tokyo Department of
Integrated Biosciences

Plants live in a very different way than we animals do. For example, they are born without deciding how many leaves and flowers they will produce in the future, how they will extend their branches, or how many organs they will produce in their lifetime. They also develop and grow according to the environment in which they are rooted. Moreover, some cells can regenerate lost organs and continue to live, while others choose to die for the other cells--What a strange way to live of plants! We are conducting research to understand the mysteries of how plants can live in such way in terms of molecules.

To understand how plants live in terms of molecules, we focus on the biopolymers RNA and cell wall polymers, to reveal their dynamics and regulatory mechanisms. For this purpose, we are studying on mosses, ferns, gymnosperms (Pinus taeda, and spruce), and angiosperms (Arabidopsis thaliana, tobacco, and poplar), by molecular genetical, molecular biological, and biochemical analyses, as well as data analyses such as comparative genomics and omics data analyses.

Our current research topics are as follows.

The high regenerative ability of plants is thought to be linked to “totipotency” of plant cells (totipotency: the ability of a single cell to get out of its differentiated state, and to differentiate into all kinds of cells). This is very different from animals, where totipotency is lost at very early stages of embryogenesis. We are conducting molecular genetics studies to elucidate the molecular mechanisms underlying the totipotency of plant cells. Based on the research findings, we are also aiming to develop efficient plant cloning and propagation techniques.

Once rooted, the plant will live its entire life in the same place. Thus, they should continuously adjust their cell activity, growth, and development according to its environment. We are focusing on RNA, which is the key to control gene expression, and the plant cell wall, which is the first barrier against the external environment, as the regulatory molecules to achieve such environmental adaptation. Elucidation of the role of these biopolymers in plant environmental response, and artificial control of plant environmental response ability by modification of biopolymers are also our targets.

For future sustainable society, we are studying molecular mechanisms of the biosynthesis of woody biomass (woody biomass: cell wall polymers in lignified secondary cell walls). We have established a basic model of the transcriptional regulatory network for secondary cell wall biosynthesis (VNS-MYB network), which is conserved among land plants. One of our findings is that this transcriptional regulatory network is differently operated by various post-transcriptional regulation of gene expression, by plant species, by environmental conditions, and by developmental stages. Based on such molecular knowledge, we challenge to create new technologies to improve the utilization of woody biomass.