title: Identification and characterization of chloroplast casein kinase II from Oryza sativa (rice).
abstract: Plastid casein kinase II is an important regulator of transcription, posttranscriptional processes, and, most likely, different metabolic functions in dicotyledonous species. Here we report the identification and characterization of pCKII from the monocotyledonous species Oryza sativa. OspCKII activity was enriched from isolated rice chloroplasts using heparin-Sepharose chromatography, in which it co-elutes with the transcriptionally active chromosome (TAC) and several ribosomal proteins. Inclusion mass scanning of the kinase-active fraction identified the gene model for OspCKII. Transient expression of GFP fused to the 184 N-terminal amino acids of the OspCKII sequence in rice confirmed the chloroplastic localization of the kinase. OspCKII activity shows the characteristic features of casein kinase II, such as the utilization of GTP as phosphate donor, inhibition by low concentrations of heparin and poly-lysine, and utilization of the canonical pCKII motif E-S-E-G-E in the model substrate RNP29. Phosphoproteome analysis of a protein extract from rice leaves combined with a meta-analysis with published phosphoproteomics data revealed differences in the target protein spectrum between rice and Arabidopsis. Consistently, several pCKII phosphorylation sites in dicotyledonous plants are not conserved in monocots and algae, suggesting that details of pCKII regulation in plastids have changed during evolution.
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Qingtao
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Shunhua
authors.initials: S
authors.lastname: Ding
authors.affiliation: Department of Biology, Plant Biotechnology, ETH Zurich, 8092 Zurich, Switzerland.
authors.forename: Sonja
authors.initials: S
authors.lastname: Reiland
authors.affiliation: Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, 06120 Halle (Saale), Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Rödiger
authors.affiliation: Functional Genomics Center Zurich, University of Zurich \ ETH Zurich, 8057 Zurich, Switzerland.
authors.forename: Bernd
authors.initials: B
authors.lastname: Roschitzki
authors.affiliation: Laboratory of Protein and Peptide Pharmaceuticals, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Xue
authors.affiliation: Department of Biology, Plant Biotechnology, ETH Zurich, 8092 Zurich, Switzerland Functional Genomics Center Zurich, University of Zurich \ ETH Zurich, 8057 Zurich, Switzerland.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Gruissem
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: Department of Biology, Plant Biotechnology, ETH Zurich, 8092 Zurich, Switzerland sacha.baginsky@biochemtech.uni-halle.de.
authors.forename: Sacha
authors.initials: S
authors.lastname: Baginsky
mesh_terms: D000595:Amino Acid Sequence; D047390:Casein Kinase II / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D060365:Chloroplast Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology* / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D060365:Chloroplast Proteins; D047390:Casein Kinase II
keywords: Casein kinase II; chloroplast; mass spectrometry; phosphorylation; substrates; transcriptionally active chromosome.