Structure of a spinach chloroplast threonine tRNA gene.

The gene for spinach chloroplast tRNAThr3 has been sequenced and is co-linear with the tRNA, does not contain an intervening sequence, and does not code for the 3'-terminal CCA, which is added post-transcriptionally. This gene shares features with prokaryotic, eukaryotic, and mitochondrial tRNA genes. The opposite strand of the tRNA gene contains a proper ribosome binding site, homology to a classical bacterial promoter, and could potentially code for a small peptide.