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Amino acid sequence variations in Nicotiana CRR4 orthologs determine the species-specific efficiency of RNA editing in plastids.

ABSTRACT: In flowering plants, RNA editing is a posttranscriptional process that converts specific C to U in organelle mRNAs. Nicotiana tabacum is an allotetraploid species derived from the progenitors of Nicotiana sylvestris and Nicotiana tomentosiformis. These Nicotiana species have been used as a model for understanding the mechanism and evolution of RNA editing in plastids. In Nicotiana species, the ndhD-1 site is edited to create the translational initiation codon of ndhD that encodes a subunit of the NAD(P)H dehydrogenease (NDH) complex. An analysis of this RNA editing revealed that editing efficiency in N. tomentosiformis is lower (15%) than that in N. tabacum (42%) and N. sylvestris (37%). However, this level of editing is sufficient for accumulating the NDH complex and its activity. The heterogous complementation of Arabidopsis crr4-3 mutant, in which RNA editing of ndhD-1 is completely impaired, with CRR4 orthologous genes derived from Nicotiana species suggested that the reduction in editing efficiency in N. tomentosiformis is caused by amino acid variations accumulating in CRR4.

SUBMITTER: Okuda K

PROVIDER: S-EPMC2577327 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Amino acid sequence variations in Nicotiana CRR4 orthologs determine the species-specific efficiency of RNA editing in plastids.

Okuda Kenji K Habata Yuya Y Kobayashi Yoshichika Y Shikanai Toshiharu T

Nucleic acids research 20080929 19

In flowering plants, RNA editing is a posttranscriptional process that converts specific C to U in organelle mRNAs. Nicotiana tabacum is an allotetraploid species derived from the progenitors of Nicotiana sylvestris and Nicotiana tomentosiformis. These Nicotiana species have been used as a model for understanding the mechanism and evolution of RNA editing in plastids. In Nicotiana species, the ndhD-1 site is edited to create the translational initiation codon of ndhD that encodes a subunit of th ...[more]

PMID: 18824480

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Amino acid sequence variations in Nicotiana CRR4 orthologs determine the species-specific efficiency of RNA editing in plastids.

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Amino acid sequence variations in Nicotiana CRR4 orthologs determine the species-specific efficiency of RNA editing in plastids.

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