title: Salinity stress in roots of contrasting barley genotypes reveals time-distinct and genotype-specific patterns for defined proteins.
abstract: Soil salinity is one of the most severe abiotic stress factors threatening agriculture worldwide. Hence, particular interest exists in unraveling mechanisms leading to salt tolerance and improved crop plant performance on saline soils. Barley is considered to be one of the most salinity-tolerant crops, but varying levels of tolerance are well characterized. A proteomic analysis of the roots of two contrasting cultivars (cv. Steptoe and cv. Morex) is presented. Young plants were exposed to a period of 1, 4, 7, or 10 d at 0, 100, or 150 mM NaCl. The root proteome was analyzed based on two-dimensional gel electrophoresis. A number of cultivar-specific and salinity stress-responsive proteins were identified. Mass spectrometry-based identification was successful for 74 proteins, and a hierarchical clustering analysis grouped these into five clusters based on similarity of expression profile. The rank product method was applied to statistically access the early and late responses, and this delivered a number of new candidate proteins underlying salinity tolerance in barley. Among these were some germin-like proteins, some pathogenesis-related proteins, and numerous as-yet uncharacterized proteins. Notably, proteins involved in detoxification pathways and terpenoid biosynthesis were detected as early responsive to salinity and may function as a means of modulating growth-regulating mechanisms and membrane stability via fine tuning of phytohormone and secondary metabolism in the root.
authors.affiliation: Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstrasse 3, 06466 Gatersleben, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Witzel
authors.forename: Andrea
authors.initials: A
authors.lastname: Matros
authors.forename: Marc
authors.initials: M
authors.lastname: Strickert
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kaspar
authors.forename: Manuela
authors.initials: M
authors.lastname: Peukert
authors.forename: Karl H
authors.initials: KH
authors.lastname: Mühling
authors.forename: Andreas
authors.initials: A
authors.lastname: Börner
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Mock
mesh_terms: D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D001467:Hordeum / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000502:physiology*; D013058:Mass Spectrometry; D018515:Plant Leaves / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D040901:Proteomics; D055049:Salt Tolerance; D012965:Sodium Chloride / Q000378:metabolism*; D013045:Species Specificity; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D012965:Sodium Chloride
keywords: barley genotypes; mass spectrometry; proteome analysis; salinity stress; two-dimensional gel electrophoresis.