title: RHON1 mediates a Rho-like activity for transcription termination in plastids of Arabidopsis thaliana.
abstract: Although transcription termination is essential to generate functional RNAs, its underlying molecular mechanisms are still poorly understood in plastids of vascular plants. Here, we show that the RNA binding protein RHON1 participates in transcriptional termination of rbcL (encoding large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase) in Arabidopsis thaliana. Inactivation of RHON1 leads to enhanced rbcL read-through transcription and to aberrant accD (encoding β-subunit of the acetyl-CoA carboxylase) transcriptional initiation, which may result from inefficient transcription termination of rbcL. RHON1 can bind to the mRNA as well as to single-stranded DNA of rbcL, displays an RNA-dependent ATPase activity, and terminates transcription of rbcL in vitro. These results suggest that RHON1 terminates rbcL transcription using an ATP-driven mechanism similar to that of Rho of Escherichia coli. This RHON1-dependent transcription termination occurs in Arabidopsis but not in rice (Oryza sativa) and appears to reflect a fundamental difference between plastomes of dicotyledonous and monocotyledonous plants. Our results point to the importance and significance of plastid transcription termination and provide insights into its machinery in an evolutionary context.
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chi
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Baoye
authors.initials: B
authors.lastname: He
authors.affiliation: Biozentrum der Ludwig-Maximilians-Universität, Plant Molecular Biology/Botany, 82152 Planegg-Martinsried, Germany.
authors.forename: Nikolay
authors.initials: N
authors.lastname: Manavski
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Mao
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Daili
authors.initials: D
authors.lastname: Ji
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Congming
authors.initials: C
authors.lastname: Lu
authors.affiliation: Departments of Molecular Biology and Plant Biology, University of Geneva, 1211 Geneva, Switzerland.
authors.forename: Jean David
authors.initials: JD
authors.lastname: Rochaix
authors.affiliation: Biozentrum der Ludwig-Maximilians-Universität, Plant Molecular Biology/Botany, 82152 Planegg-Martinsried, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Meurer
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China zhanglixin@ibcas.ac.cn.
authors.forename: Lixin
authors.initials: L
authors.lastname: Zhang
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D012275:Oryza / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics; D018087:Plastids / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D012273:Ribulose-Bisphosphate Carboxylase / Q000235:genetics*; D061806:Transcription Termination, Genetic
chemical_list: D029681:Arabidopsis Proteins; C576818:RHON1 protein, Arabidopsis; D016601:RNA-Binding Proteins; C101625:RbcL protein, plastid; D012273:Ribulose-Bisphosphate Carboxylase