Laboratories and faculty

Plant Developmental Signaling

Outline of Research and Education

Our scientific interests are centered around how plant cells acquire specialized functions and how they coordinately regulate plant growth and life cycles. Each student is engaged in a unique and important project that addresses central questions regarding plant growth and development. Our research is important not only to solve fundamental questions in basic biology, but also to gain the knowledge required to ensure food and energy security.

Major Research Topics

How root growth is regulated by endogenous and external cues

Roots have important functions, such as mechanical anchorage, nutrient and water uptake, and interaction with soil environments, and thereby support the life of whole plant bodies. In order to maximize such functions, root tissue organization, growth behavior, and metabolic activities must be precisely controlled by endogenous programs and environmental cues. While past studies have identified key regulatory factors of root development, how they coordinately regulate root growth is largely unknown. To achieve a breakthrough in this, we established a high-magnification live imaging technique to visualize gene expression and cellular/subcellular dynamics at the tip of growing roots for several days. Using this system, we are currently studying genetic and molecular mechanisms integrating endogenous and external cues to regulate root growth in changing environments (Fig. 1).

How germ cell morphologies and functions are established in plants

Germ cells, such as eggs and sperm, are functionally specialized for sexual reproduction, and at the same time have specific genomic status enabling pluripotency. Germ cell differentiation in plants takes place deep inside reproductive organs in a relatively short time window, and hence is more difficult to study than somatic cells. We solved this problem through a complementary approach using the flowering plant Arabidopsis thaliana and the liverwort Marchantia polymorpha. We successfully identified evolutionarily conserved transcription factors that promote female sexual differentiation and egg cell formation in these distantly related land plants. Functional analyses of their target genes will reveal how germ cell-specific morphologies and functions are established in plants (Fig. 2).

Fig. 1
Fig. 1
Fig. 2
Fig. 2

References

  1. Miyashima et al., Development, 138, 2303-2313, 2011
  2. Waki et al., Curr. Biol., 21, 1277-1281, 2011
  3. Waki et al., Plant J., 73, 357-367, 2013
  4. Hisanaga et al., Curr. Opin. Plant Biol., 21, 37-42, 2014
  5. Koi et al., Curr. Biol., 26, 1775-1781, 2016
  6. Kamiya et al., Development, 143, 4063-4072, 2016
  7. Nakajima, Curr. Opin. Plant Biol., 41, 110-115, 2018
  8. Miyashima et al., Nature, 565, 490–494, 2019
  9. Hisanaga et al., EMBO J., 38, e100240, 2019
  10. Hisanaga et al., Nature Plants, 5, 663–669, 2019