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RNA editing in hornwort chloroplasts makes more than half the genes functional.

ABSTRACT: RNA editing in chloroplasts alters the RNA sequence by converting C-to-U or U-to-C at a specific site. During the study of the complete nucleotide sequence of the chloroplast genome from the hornwort Anthoceros formosae, RNA editing events have been systematically investigated. A total of 509 C-to-U and 433 U-to-C conversions are identified in the transcripts of 68 genes and eight ORFs. No RNA editing is seen in any of the rRNA but one tRNA suffered a C-to-U conversion at an anticodon. All nonsense codons in 52 protein-coding genes and seven ORFs are removed in the transcripts by U-to-C conversions, and five initiation and three termination codons are created by C-to-U conversions. RNA editing in intron sequence suggests that editing can precede intercistronic processing. The sequence complementary to the edited site is proposed as a distant cis-recognition element.

SUBMITTER: Kugita M

PROVIDER: S-EPMC154213 | biostudies-literature | 2003 May

REPOSITORIES: biostudies-literature

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RNA editing in hornwort chloroplasts makes more than half the genes functional.

Kugita Masanori M Yamamoto Yuhei Y Fujikawa Takeshi T Matsumoto Tohoru T Yoshinaga Koichi K

Nucleic acids research 20030501 9

RNA editing in chloroplasts alters the RNA sequence by converting C-to-U or U-to-C at a specific site. During the study of the complete nucleotide sequence of the chloroplast genome from the hornwort Anthoceros formosae, RNA editing events have been systematically investigated. A total of 509 C-to-U and 433 U-to-C conversions are identified in the transcripts of 68 genes and eight ORFs. No RNA editing is seen in any of the rRNA but one tRNA suffered a C-to-U conversion at an anticodon. All nonse ...[more]

PMID: 12711687

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