A novel plant nuclear gene encoding chloroplast ribosomal protein S9 has atransit peptide related to that of rice chloroplast ribosomal protein L12

We have cloned a novel nuclear gene for a ribosomal protein of rice and Ara bidopsis that is like the bacterial ribosomal protein S9, To determine the subcellular localization of the gene product, we fused the N-terminal regio n and green fluorescent protein and expressed it transiently in rice seedli ngs, Localized fluorescence was detectable only in chloroplasts, indicating that this nuclear gene encodes chloroplast ribosomal protein S9, The N-ter minal region of rice ribosomal protein S9 was found to have a high sequence similarity to the transit peptide region of the rice chloroplast ribosomal protein L12, suggesting that these transit peptides have a common lineage. (C) 1999 Federation of European Biochemical Societies.