title: Rice cyclophilin OsCYP18-2 is translocated to the nucleus by an interaction with SKIP and enhances drought tolerance in rice and Arabidopsis.
abstract: Cyclophilin 18-2 (CYP18-2) genes, homologues of human peptidyl-prolyl isomerase-like 1 (PPiL1), are conserved across multicellular organisms and Schizosaccharomyces pombe. Although PPiL1 is known to interact with ski-interacting protein (SKIP), a transcriptional co-regulator and spliceosomal component, there have been no functional analyses of PPiL1 homologues in plants. Rice cyclophilin 18-2 (OsCYP18-2) bound directly to amino acids 56-95 of OsSKIP and its binding was independent of cyclosporin A, a cyclophilin-binding drug. Moreover, OsCYP18-2 exhibited PPIase activity regardless of its interaction with OsSKIP. Therefore, the binding site for OsCYP18-2's interaction with SKIP was distinct from the PPIase active site. OsCYP18-2's interaction with SKIP full-length protein enabled OsCYP18-2's translocation from the cytoplasm into the nucleus and AtSKIP interacted in planta with both AtCYP18-2 and OsCYP18-2. Drought and salt stress induced similar expression of OsCYP18-2 and OsSKIP. Overexpression of OsCYP18-2 in transgenic rice and Arabidopsis thaliana plants enhanced drought tolerance and altered expression and pre-mRNA splicing patterns of stress-related genes in Arabidopsis under drought conditions. Furthermore, OsCYP18-2 caused transcriptional activation with/without OsSKIP in the GAL4 system of yeast; thus the OsSKIP-OsCYP18-2 interaction has an important role in the transcriptional and post-transcriptional regulation of stress-related genes and increases tolerance to drought stress.
authors.affiliation: Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea.
authors.forename: Sang Sook
authors.initials: SS
authors.lastname: Lee
authors.affiliation: Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea.
authors.forename: Hyun Ji
authors.initials: HJ
authors.lastname: Park
authors.affiliation: Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea.|Department of Pharmacology, College of Medicine, Seonam University, Namwon, 590-170, Korea.
authors.forename: Dae Hwa
authors.initials: DH
authors.lastname: Yoon
authors.affiliation: Divisions of Bio-Crops Development, National Academy of Agricultural Science, Rural Development Administration, Suwon, 441-707, Korea.
authors.forename: Beom-Gi
authors.initials: BG
authors.lastname: Kim
authors.affiliation: Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea.|Department of Pharmacology, College of Medicine, Seonam University, Namwon, 590-170, Korea.
authors.forename: Jun Cheul
authors.initials: JC
authors.lastname: Ahn
authors.affiliation: Department of Plant and Microbial Biology, University of California at Berkeley, Berkeley, CA, 73072, USA.
authors.forename: Sheng
authors.initials: S
authors.lastname: Luan
authors.affiliation: Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea.
authors.forename: Hye Sun
authors.initials: HS
authors.lastname: Cho
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism; D021983:Cyclophilins / Q000235:genetics / Q000378:metabolism*; D055864:Droughts; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D008954:Models, Biological; D012275:Oryza / Q000235:genetics / Q000502:physiology*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D055049:Salt Tolerance; D036226:Seedlings / Q000235:genetics / Q000502:physiology; D013312:Stress, Physiological; D015533:Transcriptional Activation; D014867:Water / Q000502:physiology
chemical_list: D010940:Plant Proteins; D014867:Water; D021983:Cyclophilins
keywords: SKIP-interacting protein; rice (Oryza sativa L.); splicing; transcriptional activation