Abstract
Rice is a Si-accumulating plant. To isolate a gene which is responsible for Si uptake in rice, we have isolated a mutant (lsi1) which is defective in the xylem loading of Si (Ma et al., 2002). In the present study, the gene Lsi1 was isolated by map-based cloning technique. The cDNA was 1409 bp long and the deduced protein consisted of 298 residues. The program PSORT predicts that the Lsi1 encodes a membrane protein. This gene was not induced by Si and constitutively expressed mainly in the roots. To investigate cellular localization of LSI1, Lsi1 was fused with GFP and introduced the tobacco leaves and onion epidermal cells. Microscopic observation showed that LSI1 was localized in the memblane. Further functional analysis of this gene is currently being undertaken.
