A model system to study the lignification process in Eucalyptus globulus

Authors

  • Pedro Araújo,

    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    Search for more papers by this author
  • Igor Cesarino,

    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    2. Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium
    3. Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium
    Search for more papers by this author
  • Juliana Lischka Sampaio Mayer,

    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    Search for more papers by this author
  • Ilse Fernanda Ferrari,

    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    Search for more papers by this author
  • Eduardo Kiyota,

    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    Search for more papers by this author
  • Alexandra Christine Helena Frankland Sawaya,

    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    Search for more papers by this author
  • Adriana Franco Paes Leme,

    1. Laboratório Nacional de Biociências, CNPEM/ABTLuS, Campinas, Brazil
    Search for more papers by this author
  • Paulo Mazzafera

    Corresponding author
    1. Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil
    Search for more papers by this author

Abstract

Recalcitrance of plant biomass is closely related to the presence of the phenolic heteropolymer lignin in secondary cell walls, which has a negative effect on forage digestibility, biomass-to-biofuels conversion and chemical pulping. The genus Eucalyptus is the main source of wood for pulp and paper industry. However, when compared to model plants such as Arabidopsis thaliana and poplar, relatively little is known about lignin biosynthesis in Eucalyptus and only a few genes were functionally characterized. An efficient, fast and inexpensive in vitro system was developed to study lignification in Eucalyptus globulus and to evaluate the potential role of candidate genes in this biological process. Seedlings were grown in four different conditions, in the presence or absence of light and with or without sucrose in the growth medium, and several aspects of lignin metabolism were evaluated. Our results showed that light and, to a lesser extent, sucrose induced lignin biosynthesis, which was followed by changes in S/G ratio, lignin oligomers accumulation and gene expression. In addition, higher total peroxidase activity and differential isoperoxidase profile were observed when seedlings were grown in the presence of light and sucrose. Peptide sequencing allowed the identification of differentially expressed peroxidases, which can be considered potential candidate class III peroxidases involved in lignin polymerization in E. globulus.

Ancillary