silicon transporter in rice

• Published in: Nature 2006-03, Vol.440 (7084), p.688-691
• Main Authors: Ma, J.F, Tamai, K, Yamaji, N, Mitani, N, Konishi, S, Katsuhara, M, Ishiguro, M, Murata, Y, Yano, M
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; amino acid sequences; Animals; aquaporins; Aquaporins - chemistry; Aquaporins - genetics; Aquaporins - metabolism; Base Sequence; Biological and medical sciences; Biological Transport; Botany; Cell Membrane - metabolism; Cell physiology; complementary DNA; Crop production; Fundamental and applied biological sciences. Psychology; Gene Expression Profiling; genes; Genes, Plant - genetics; Genetic research; Humanities and Social Sciences; letter; Lodging; Lsi1 gene; membrane proteins; Membranes; Models, Molecular; Molecular Sequence Data; multidisciplinary; mutants; Mutation - genetics; nucleotide sequences; nutrient transport; Oocytes - metabolism; Oryza - cytology; Oryza - genetics; Oryza - metabolism; Oryza sativa; Pests; Phenotype; physiological transport; Plant Epidermis - cytology; Plant growth; Plant physiology and development; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Roots - genetics; Plant Roots - metabolism; Plasma membrane and permeation; Rice; Roots; Science; Science (multidisciplinary); Silicon; Silicon - metabolism; Sustainable production; transporters; Xenopus; Xenopus laevis
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/nature04590

Silicon is beneficial to plant growth and helps plants to overcome abiotic and biotic stresses by preventing lodging (falling over) and increasing resistance to pests and diseases, as well as other stresses. Silicon is essential for high and sustainable production of rice, but the molecular mechanism responsible for the uptake of silicon is unknown. Here we describe the Low silicon rice 1 (Lsi1) gene, which controls silicon accumulation in rice, a typical silicon-accumulating plant. This gene belongs to the aquaporin family and is constitutively expressed in the roots. Lsi1 is localized on the plasma membrane of the distal side of both exodermis and endodermis cells, where casparian strips are located. Suppression of Lsi1 expression resulted in reduced silicon uptake. Furthermore, expression of Lsi1 in Xenopus oocytes showed transport activity for silicon only. The identification of a silicon transporter provides both an insight into the silicon uptake system in plants, and a new strategy for producing crops with high resistance to multiple stresses by genetic modification of the root's silicon uptake capacity.