title: Euglena gracilis chloroplast psbB, psbT, psbH and psbN gene cluster: regulation of psbB-psbT pre-mRNA processing.
abstract: A 2.4 kb region of the Euglena gracilis chloroplast genome containing the genes psbT, psbH and psbN was characterized. The mRNAs transcribed from psbB, psbT, psbH and psbN were analyzed by northern hybridization, S1 nuclease protection analysis and primer extension RNA sequencing. The gene pairs psbB-psbT and psbH-psbN are cotranscribed from opposite strands. The 5' end of the psbN-psbH transcript and the intercistronic cleavage sites between psbB-psbT and psbN-psbH were determined. The extent of psbB-psbT intercistronic cleavage is greater during photoautotrophic than heterotrophic growth and thus may be developmentally regulated. Processing is absent in the non-photosynthetic E. gracilis mutant Y9Z1NaL.
authors.affiliation: Department of Biochemistry, University of Arizona, Tucson 85721, USA.
authors.forename: L
authors.initials: L
authors.lastname: Hong
authors.forename: J K
authors.initials: JK
authors.lastname: Stevenson
authors.forename: W B
authors.initials: WB
authors.lastname: Roth
authors.forename: R B
authors.initials: RB
authors.lastname: Hallick
mesh_terms: D000818:Animals; D001483:Base Sequence; D002736:Chloroplasts / Q000235:genetics*; D018076:DNA, Complementary; D005056:Euglena gracilis / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009154:Mutation; D009876:Operon; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics*; D012322:RNA Precursors / Q000235:genetics*; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D045322:Photosynthetic Reaction Center Complex Proteins; D012322:RNA Precursors; D015719:Single-Strand Specific DNA and RNA Endonucleases