title: Quantitative proteomics analysis reveals that the nuclear cap-binding complex proteins arabidopsis CBP20 and CBP80 modulate the salt stress response.
abstract: The cap-binding proteins CBP20 and CBP80 have well-established roles in RNA metabolism and plant growth and development. Although these proteins are thought to be involved in the plant's response to environmental stress, their functions in this process are unclear. Here we demonstrated that Arabidopsis cbp20 and cbp80 null mutants had abnormal leaves and flowers and exhibited increased sensitivity to salt stress. The aberrant phenotypes were more pronounced in the cbp20/80 double mutant. Quantification by iTRAQ (isobaric tags for relative and absolute quantification) identified 77 differentially expressed proteins in the cbp20 and cbp80 lines compared with the wild-type Col-0 under salt stress conditions. Most of these differentially expressed proteins were synergistically expressed in cbp20 and cbp80, suggesting that CBP20 and CBP80 have synergistic roles during the salt stress response. Biochemical analysis demonstrated that CBP20 and CBP80 physically interacted with each other. Further analysis revealed that CBP20/80 regulated the splicing of genes involved in proline and sugar metabolism and that the epigenetic and post-translational modifications of these genes were involved in salt stress tolerance. Our data suggest a link between CBP20/80-dependent protein ubiquitination/sumoylation and the salt stress response.
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, ‡Plant Germplasm and Genomics Center, the Germplasm Bank of Wild Species, and §Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Science , No. 132 Lanhei Road, Heilongtan, Kunming 650204, China.
authors.forename: Xiangxiang
authors.initials: X
authors.lastname: Kong
authors.forename: Lan
authors.initials: L
authors.lastname: Ma
authors.forename: Liming
authors.initials: L
authors.lastname: Yang
authors.forename: Qian
authors.initials: Q
authors.lastname: Chen
authors.forename: Nan
authors.initials: N
authors.lastname: Xiang
authors.forename: Yongping
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Hu
mesh_terms: D017398:Alternative Splicing; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D020869:Gene Expression Profiling / Q000379:methods; D018506:Gene Expression Regulation, Plant; D015151:Immunoblotting; D009154:Mutation; D039502:Nuclear Cap-Binding Protein Complex / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D020543:Proteome / Q000235:genetics / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055049:Salt Tolerance / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D039381:RNA Cap-Binding Proteins
chemical_list: D029681:Arabidopsis Proteins; D039502:Nuclear Cap-Binding Protein Complex; D021122:Protein Subunits; D020543:Proteome; D016601:RNA-Binding Proteins; D014157:Transcription Factors; C454128:CBP20 protein, Arabidopsis; C562191:indeterminate(ID)-domain 14 protein, Arabidopsis; C435105:At2g13540 protein, Arabidopsis; D039381:RNA Cap-Binding Proteins