A novel additional group II intron distinguishes the mitochondrial rps3 gene in gymnosperms.

摘要: Comparative analysis of the ribosomal protein S3 gene (rps3) in mitochondrial genome Cycas with newly sequenced counterparts from Magnolia and Helianthus available sequences higher plants revealed that positional clustering genes for S19 (rps19) L16 (rpl16) is preserved gymnosperms. However, contrast to other land plant species, rps3 mitochondria unique possessing a second intron: rps3i2. Reverse transcription–polymerase chain reaction (RT-PCR) transcripts generated rps19–rps3–rpl16 cluster demonstrated are cotranscribed extensively modified by RNA editing both introns efficiently spliced. Despite remarkable size heterogeneity, rps3i1 can be shown homologous group IIA present within algae plants, including Helianthus. Conversely, similar rps3i2 have not been reported previously. On basis conserved primary secondary structure intervening sequence interrupting Cycasrps3 has classified as II intron. The close relationship different intriguing suggestive derivation this novel sequence. Interestingly, appears at same location Furthermore, pattern distribution among provides evidence evolutionary acquisition intron gymnosperms via intragenomic transposition or retrotransposition.