Silicon transporters
Silicon (Si) is the most abundant mineral element in soil. It can help plants to overcome various abiotic and biotic stresses. High accumulation of Si is especially important for high and sustainable production of rice, a typical Si-accumulating species. We have identified three transporters involved in Si accumulation in rice. Lsi1 and Lsi2 are responsible for Si uptake in the roots. Lsi1 is localized at the distal side, whereas Lsi2 at the proximal side of both exodermis and endodermis cells. Lsi6 is localized at the xylem parenchyma cells of leaf blade and sheath, and xylem transfer cells of nodes. It is responsible for xylem unloading of Si and inter-vascular transfer of Si. In addition, we also have identified similar transporters in barley, wheat, maize and cucumber.
Key publications
- Ma, J. F., Tamai, K., Yamaji, N., Mitani, N., Konishi, S., Katsuhara, M., Ishiguro, M., Murata, Y. and Yano, M. 2006. A silicon transporter in rice. Nature 440: 688-691.
- Ma, J. F., Yamaji, N., Mitani, N.,Tamai, K., Konishi, S., Fujiwara, T., Katsuhara, M. and Yano, M. 2007. An efflux transporter of silicon in rice. Nature 448: 209-211
- Ma, J. F. and Yamaji, N. 2006. Silicon uptake and accumulation in higher plants. Trends in Plant Sci. 11, 392-397.
- Yamaji, N., Mitatni, N. and Ma, J. F. 2008. A Transporter regulating silicon distribution in rice shoots. Plant Cell 20: 1381-1389.
- Yamaji, N. and Ma, J. F. 2009. A transporter at the node responsible for inter-vascular transfer of silicon in rice. Plant Cell 21:2878-2883
- Mitani, N., Chiba, Y., Yamaji, N. and Ma, J. F. 2009. Identification and characterization of maize and barley Lsi-2-like silicon efflux transporters reveals a distinct silicon uptake system from that in rice. Plant Cell 21:2133-2142.
- Mitani, N., Yamaji, N., Ago, Y., Iwasaki, K. and Ma, J. F. 2011. Isolation and functional characterization of an influx silicon transporter in two pumpkin cultivars contrasting in Si accumulation.Plant J., 66: 231–240.
