title: Site-specific factor involved in the editing of the psbL mRNA in tobacco plastids.
abstract: In tobacco plastids, functional psbL mRNA is created by editing an ACG codon to an AUG translation initiation codon. To determine if editing may occur in a chimeric mRNA, the N-terminal part of psbL containing the editing site was translationally fused with the aadA and kan bacterial genes. The chimeric constructs were introduced into the tobacco plastid genome by targeted gene insertion. Editing of the chimeric mRNAs indicated that the 98 nt fragment spanning the psbL editing site contains all cis information required for editing. Expression of the chimeric gene transcripts led to a significant decrease in the editing efficiency of the endogenous psbL mRNA. However, the efficiency of editing in the transplastomic lines was unchanged for four sites in the rpoB and ndhB mRNAs. Reduced efficiency of psbL editing, but not of the other four sites, in the transplastomic lines indicates depletion of psbL-specific editing factor(s). This finding implicates the involvement of site-specific factors in editing of plastid mRNAs in higher plants.
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, Piscataway 08855-0759, USA.
authors.forename: S
authors.initials: S
authors.lastname: Chaudhuri
authors.forename: H
authors.initials: H
authors.lastname: Carrer
authors.forename: P
authors.initials: P
authors.lastname: Maliga
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004274:DNA, Recombinant; D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D018390:Gene Targeting; D017343:Genes, Plant / Q000235:genetics; D019868:Kanamycin Kinase; D008969:Molecular Sequence Data; D009713:Nucleotidyltransferases / Q000235:genetics; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics*; D045332:Photosystem II Protein Complex; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D018087:Plastids / Q000235:genetics*; D017393:RNA Editing / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics*; D014026:Nicotiana / Q000235:genetics
chemical_list: D004274:DNA, Recombinant; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; C075419:photosystem II, psbL subunit; D017853:Phosphotransferases (Alcohol Group Acceptor); D019868:Kanamycin Kinase; D009713:Nucleotidyltransferases; C022678:streptomycin 3''-adenylyltransferase; D012321:DNA-Directed RNA Polymerases