Abstract
RNA editing alters genomic nucleotide sequences at the transcript level. In land plant chloroplasts, C-to-U conversion is known to occur at 20 to 30 sites. However, little is known about the site-recognition mechanism and physiological meanings of RNA editing. We have identified systematically editing sites in chloroplast transcripts from Nicotiana tabacum and its progenitors, N. sylvestris and N. tomentosiformis, rice and pea. In silico analysis was carried out for these sites together with those reported in maize and Arabidopsis to search for possible elements for site-recognition. Using our in vitro RNA editing system, the cis-elements of four editing sites were identified. For analysis of a large number of RNA editing site, simple/efficient systems are necessary. We successfully developed a convenient in vitro editing system to, using non-RI, from tobacco chloroplasts.
