title: Integrative "omic" analysis reveals distinctive cold responses in leaves and roots of strawberry, Fragaria × ananassa 'Korona'.
abstract: To assess underlying metabolic processes and regulatory mechanisms during cold exposure of strawberry, integrative "omic" approaches were applied to Fragaria × ananassa Duch. 'Korona.' Both root and leaf tissues were examined for responses to the cold acclimation processes. Levels of metabolites, proteins, and transcripts in tissues from plants grown at 18°C were compared to those following 1-10 days of cold (2°C) exposure. When leaves and roots were subjected to GC/TOF-MS-based metabolite profiling, about 160 compounds comprising mostly structurally annotated primary and secondary metabolites, were found. Overall, 'Korona' showed a modest increase of protective metabolites such as amino acids (aspartic acid, leucine, isoleucine, and valine), pentoses, phosphorylated and non-phosphorylated hexoses, and distinct compounds of the raffinose pathway (galactinol and raffinose). Distinctive responses were observed in roots and leaves. By 2DE proteomics a total of 845 spots were observed in leaves; 4.6% changed significantly in response to cold. Twenty-one proteins were identified, many of which were associated with general metabolism or photosynthesis. Transcript levels in leaves were determined by microarray, where dozens of cold associated transcripts were quantitatively characterized, and levels of several potential key contributors (e.g., the dehydrin COR47 and GADb) to cold tolerance were confirmed by qRT-PCR. Cold responses are placed within the existing knowledge base of low temperature-induced changes in plants, allowing an evaluation of the uniqueness or generality of Fragaria responses in photosynthetic tissues. Overall, the cold response characteristics of 'Korona' are consistent with a moderately cold tolerant plant.
authors.affiliation: Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis IN, USA.
authors.forename: Gage
authors.initials: G
authors.lastname: Koehler
authors.affiliation: Department of Biology, Norwegian University of Science and Technology Trondheim, Norway.
authors.forename: Jens
authors.initials: J
authors.lastname: Rohloff
authors.affiliation: Department of Natural Sciences and Technology, Hedmark University College Hamar, Norway.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Wilson
authors.affiliation: Max Planck Institute of Molecular Plant Physiology Potsdam, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Kopka
authors.affiliation: Max Planck Institute of Molecular Plant Physiology Potsdam, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Erban
authors.affiliation: Department of Biology, Norwegian University of Science and Technology Trondheim, Norway.
authors.forename: Per
authors.initials: P
authors.lastname: Winge
authors.affiliation: Department of Biology, Norwegian University of Science and Technology Trondheim, Norway.
authors.forename: Atle M
authors.initials: AM
authors.lastname: Bones
authors.affiliation: Bioforsk, Norwegian Institute for Agricultural and Environmental Research - Grassland and Landscape Division Kvithamar, Norway.
authors.forename: Jahn
authors.initials: J
authors.lastname: Davik
authors.affiliation: Graminor Breeding Ltd. Ridabu, Norway ; Department of Plant Sciences, Norwegian University of Life Sciences Ås, Norway.
authors.forename: Muath K
authors.initials: MK
authors.lastname: Alsheikh
authors.affiliation: Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis IN, USA.
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Randall
keywords: Fragaria; Korona; acclimation; cold; metabolome; proteome; tolerance; transcriptome