Lupin chloroplast and mitochondrial tRNA populations and their genes.

Transfer RNAs isolated from lupin chloroplasts and mitochondria were compared by two-dimensional gel electrophoresis. Twenty chloroplast and 24 mitochondrial tRNA species were identified. The saturation hybridization between lupin chloroplast DNA and 125I-labelled lupin chloroplast tRNAs pointed to the presence of about 34 tRNA genes in lupin chloroplast DNA. The number of mitochondrial tRNA genes estimated by the same method was about 30 genes. EcoRI restriction digest of lupin mitochondrial DNA probed with 32P-labelled lupin mitochondrial tRNAs revealed only a small number of positive restriction fragments. Some of these mitochondrial restriction fragments hybridized with 32P-labelled chloroplast tRNA.