Abstract
Rice is known as a Si-accumulating plant, but the mechanism responsible for high Si uptake is poorly understood. We have isolated a rice gene (Lsi1) which is associated with Si uptake. In the present study, we report a novel rice gene (Lsi2) for Si uptake. Rough mapping showed that (Lsi2) was located on chromosome 3. Fining mapping resulted in identification of (Lsi2) candidate region of 106 kb, which is predicated to contain 17 candidate genes. Sequence analysis revealed that a single nucleotide substitution occurs at one candidate gene in the mutant. The protein encoded by this gene shows a high similarity to a putative anion transporter. To confirm the function of this gene, complementation test was conducted by introducing a genomic DNA containing the (Lsi2) region into the mutant. Result shows that the Si uptake in the transgenic plants was recovered, indicating that (Lsi2) gene is responsible for Si uptake.
