title: Peroxidase 4 is involved in syringyl lignin formation in Arabidopsis thaliana.
abstract: Syringyl lignins result from the oxidative polymerization of sinapyl alcohol in a reaction mediated by syringyl (basic) peroxidases. Several peroxidases have been identified in the genome of Arabidopsis thaliana as close homologues to ZePrx, the best characterized basic peroxidase so far, but none of these has been directly involved in lignification. We have used a knock-out mutant of AtPrx4, the closest homologue to ZePrx, to study the involvement of this basic peroxidase in the physiology of the plant under both long- and short-day light conditions. Our results suggest that AtPrx4 is involved in cell wall lignification, especially in syringyl monomer formation. The disruption of AtPrx4 causes a decrease in syringyl units proportion, but only when light conditions are optimal. Moreover, the effect of AtPrx4 disruption is age-dependent, and it is only significant when the elongation process of the stem has ceased and lignification becomes active. In conclusion, AtPrx4 emerges as a basic peroxidase regulated by day length with an important role in lignification.
authors.affiliation: Department of Plant Biology, University of Murcia, Murcia 30100, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Fernández-Pérez
authors.affiliation: Department of Plant Biology, University of Murcia, Murcia 30100, Spain.
authors.forename: Tamara
authors.initials: T
authors.lastname: Vivar
authors.affiliation: Deparment of Animal Biology, Plant Biology and Ecology, University of A Coruña, A Coruña 15071, Spain.
authors.forename: Federico
authors.initials: F
authors.lastname: Pomar
authors.affiliation: Department of Plant Biology, University of Murcia, Murcia 30100, Spain.
authors.forename: María A
authors.initials: MA
authors.lastname: Pedreño
authors.affiliation: Department of Plant Biology, University of Murcia, Murcia 30100, Spain. Electronic address: enovo@um.es.
authors.forename: Esther
authors.initials: E
authors.lastname: Novo-Uzal
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008031:Lignin / Q000378:metabolism*; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000235:genetics / Q000378:metabolism*; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D018547:Plant Stems / Q000201:enzymology / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D008031:Lignin; D010544:Peroxidases; C000605117:peroxidase 4, Arabidopsis; D009195:Peroxidase
keywords: Arabidopsis; Cell wall; Lignification; Peroxidase; Syringyl