title: A proteomic approach to Physcomitrella patens rhizoid exudates.
abstract: The interaction between plants and the surrounding environment has been widely studied, specially the defence reactions and the plant-plant interactions. One of the most remarkable metabolic features of plant roots is the ability to secrete a vast array of compounds into the rhizosphere, not only of low molecular weight but also polysaccharides and proteins. Here, we took advantage of proteomics to study the rhizoid exudates of Physcomitrella patens at early and late development stages (7 and 28 days of culture in liquid medium). Samples were extracted, separated and detected with nanoLC-MALDI-TOF/TOF MS/MS, identifying 47 proteins at the development stage of 7 days, and 66 proteins at 28 days. Moreover, 21 proteins were common to the two analyzed periods. All the identified proteins were classified into 8 functional categories: response to stress, response to stimulus, oxido-reduction, cell wall modification, photosynthesis and carbohydrate metabolism, transport, DNA metabolic process and regulation/signalling. Our results show important differences in the protein expression profile along the development of P. patens, mainly at the level of regulation- and senescence-related proteins. Defence-related proteins, such as chitinases, thaumatins and peroxidases have a major role in the interaction of P. patens with the environment.
authors.affiliation: Department of Animal Biology, Plant Biology and Ecology. University of A Coruña, E-15071 A Coruña, Spain; Present address: IBMC. University of Porto, E- 4150-180 Porto, Portugal.
authors.forename: Teresa
authors.initials: T
authors.lastname: Martínez-Cortés
authors.affiliation: Department of Animal Biology, Plant Biology and Ecology. University of A Coruña, E-15071 A Coruña, Spain.
authors.forename: Federico
authors.initials: F
authors.lastname: Pomar
authors.affiliation: Department of Animal Biology, Plant Biology and Ecology. University of A Coruña, E-15071 A Coruña, Spain.
authors.forename: Fuencisla
authors.initials: F
authors.lastname: Merino
authors.affiliation: Department of Plant Biology. University of Murcia. E-30100 Murcia, Spain. Electronic address: enovo@um.es.
authors.forename: Esther
authors.initials: E
authors.lastname: Novo-Uzal
mesh_terms: D019068:Bryopsida / Q000235:genetics / Q000378:metabolism*; D056148:Chromatography, Reverse-Phase; D063990:Gene Ontology; D013058:Mass Spectrometry; D010788:Photosynthesis; D053147:Plant Exudates / Q000378:metabolism; D010940:Plant Proteins / Q000145:classification / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013312:Stress, Physiological
chemical_list: D053147:Plant Exudates; D010940:Plant Proteins; D020543:Proteome
keywords: Defence; Exudate; NanoLC-MALDI-TOF/TOF; Physcomitrella patens; Proteome; Rhizoids