Edited transcripts compete with unedited mRNAs for trans-acting editing factors in higher plant chloroplasts.
Chloroplast RNA transcripts of vascular plants undergo C to U editing at approximately 30 sites, but there is no consensus sequence that identifies a C to be edited. Both sequences closely surrounding an edited C and unidentified site-specific trans-acting factors have been shown to be important for editing. The ability of an already edited transgenic sequence to bind and thus titrate a trans-acting editing factor was evaluated for two editing sites, ndhF and rpoB site 2. The U-containing rpoB transcripts did not affect editing of the endogenous rpoB transcripts, likely because the comparable C-containing transcripts containing 27 nucleotides surrounding the edited C were only 20% edited, indicating a low affinity of a trans-factor for this length of edited sequence. Surprisingly, U-containing ndhF transgene transcripts reduced endogenous ndhF transcript editing to the same degree as a C-containing transgene transcript. This indicates that the C target of editing is not a critical recognition feature for the site-specific trans-acting factor.
Reed
M L
ML
Department of Molecular Biology and Genetics, Biotechnology Building, Cornell University, Ithaca, NY 14853, USA.
Lyi
S M
SM
Hanson
M R
MR
D001665:Binding Sites / Q000235:genetics; D002736:Chloroplasts / Q000235:genetics*; D018742:DNA, Chloroplast / Q000235:genetics; D012321:DNA-Directed RNA Polymerases; D009245:NADH Dehydrogenase / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics; D010947:Plants, Toxic; D010957:Plasmids / Q000235:genetics; D017393:RNA Editing; D012333:RNA, Messenger / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics; D014158:Transcription, Genetic; D014170:Transformation, Genetic
D018742:DNA, Chloroplast; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; C101305:RpoB protein, Oryza sativa; C489904:NdhF protein, plant; D009245:NADH Dehydrogenase; D012321:DNA-Directed RNA Polymerases