A01-3:Bio-metal sensing mechanisms in plants
Junpei Takano
(Graduate School of Life and Environmental Sciences, Osaka Prefecture University)
Lab website

Plants take up essential metal and metalloid elements, bio-metals, via roots. Because both deficiency and toxicity affect plant growth and survival, uptake and translocation of bio-metals need to be regulated. Indeed, concentrations of bio-metals are sensed in or out of the cells to control the abundance and activity of transport proteins. For example, an Arabidopsis borate exporter BOR1, which functions in boron translocation under low boron conditions, undergoes endocytosis from the plasma membrane and degradation in the vacuole upon high boron supply. This is an efficient mechanism to avoid accumulation of the metalloid to toxic levels in tissues. In this project, we explore functions and structural dynamics of transporters with sensing functions, so called transceptors, of bio-metals. Furthermore, we will apply the outcomes of the bio-metal projects to generate crop plants with efficient utilization or high accumulation of bio-metals and low-accumulation of harmful elements.

Major publications
A. Yoshinari, T. Hosokawa, T. Amano, M. P. Beier, T. Kunieda, T. Shimada, I. Hara-Nishimura, S. Naito, and *J. Takano
“Polar Localization of the Borate Exporter BOR1 Requires AP2 Dependent endocytosis”
Plant Physiology, 2019, 179, 1569–1580
doi: 10.1104/pp.18.01017

M. Fukuda, S. Wakuta, J. Kamiyo, T. Fujiwara, and *J. Takano
“Establishment of Genetically Encoded Biosensors for Cytosolic Boric Acid in Plant Cell”
The Plant Journal, 2018, 95, 763−774
doi: 10.1111/tpj.13985

S. Wang, A. Yoshinari, T. Shimada, I. Hara-Nishimura, N. Mitani-Ueno, J. F. Ma, S. Naito, and *J. Takano
“Polar localization of the NIP5;1 boric acid channel is maintained by endocytosis and failitates boron transport in Arabidopsis roots”
The Plant Cell, 2017, 29, 824-842
doi: 10.1105/tpc.16.00825

*J. Takano, M. Tanaka, A. Toyoda, K. Miwa, K. Kasai, K. Fuji, H. Onouchi, S. Naito, and T. Fujiwara
“Polar localization and degradation of Arabidopsis boron transporters through distinct trafficking pathways”
Proceedings of the National Academy of Sciences, USA, 2010, 107, 5220-5225
doi: 10.1073/pnas.0910744107

J. Takano, K. Miwa, L. Yuan, N. von Wirén, and *T. Fujiwara
“Endocytosis and degradation of BOR1, a boron transporter of Arabidopsis thaliana, regulated by boron availability”
Proceedings of the National Academy of Sciences, USA, 2005, 102, 12276-12281
doi: 10.1073/pnas.0502060102