The ‘divided’ gene for chloroplast ribosomal protein S12 consists of 3 exons and the first exon (5'-rps12) is located far from the second and third exons (3'-rps12) in the tobacco chloroplast genome. Northern blot hybridization revealed that both 5'-rps12 and 3'-rps12 are transcribed in the chloroplasts. Reverse transcription analysis indicated that trans splicing between the 5'-rps12 and 3'-rps12 transcripts occurs in vivo.
