title: Analysis of the nuclear proteome of the resurrection plant Xerophyta viscosa in response to dehydration stress using iTRAQ with 2DLC and tandem mass spectrometry.
abstract: Xerophyta viscosa Baker (family Velloziaceae) is a desiccation tolerant plant which survives extremes of dehydration down to 5% relative water content (RWC) and resumes full physiological activity within 80h of rehydration. The nuclear proteome of Xerophyta viscosa and its response to dehydration at 35% RWC as compared to fully hydrated plants was analysed using iTRAQ together with 2DLC and ESI-MS/MS. RWC at 35% is unique for desiccation tolerant species as it represents a distinct phase of the dehydration process where induction of late protection mechanisms are initiated. We reproducibly identified 122 proteins with confidence≥95% (ρ<0.05). In response to dehydration, 65% of the identified proteins had the same protein abundance as the hydrated, 22% were shown to be more abundant while 9.8% were less abundant. Classification of the nuclear proteins according to GO annotation showed that most proteins were part of cellular processes (77.43%) and had binding activity (85.47%) respectively. Ontological classification according to Interpro and Pfam databases categorized most nuclear proteins as part of gene regulation (21%) while the functions of the mapped proteins using MapMan showed involvement in protein synthesis (22%), degradation (9%), DNA structure (8%) and regulation (8%).
authors.affiliation: Department of Molecular and Cellular Biology, University of Cape Town, Private Bag, Rondebosch 7701, South Africa.
authors.forename: Kamal Omer
authors.initials: KO
authors.lastname: Abdalla
authors.forename: Mohamed Suhail
authors.initials: MS
authors.lastname: Rafudeen
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D003681:Dehydration / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D019684:Magnoliopsida / Q000737:chemistry / Q000378:metabolism*; D008954:Models, Biological; D009687:Nuclear Proteins / Q000032:analysis* / Q000378:metabolism; D010940:Plant Proteins / Q000032:analysis* / Q000378:metabolism; D020543:Proteome / Q000032:analysis / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D013312:Stress, Physiological / Q000502:physiology; D053719:Tandem Mass Spectrometry
chemical_list: D009687:Nuclear Proteins; D010940:Plant Proteins; D020543:Proteome