Abstract

Yellow Lupin (Lupinus luteus L.) is a promising protein source for fish nutrition. The superior seed protein content present in this species (45-58%), however, is accompanied by variable concentrations of Raffinose Family Oligosaccharides (RFOs), which cause flatulence in monogastric animals. RFOs concentration has been shown to increase in plants under stress conditions, suggesting a role on stress tolerance. Therefore, it is imperative to determine the exact roles that RFOs play on plant fitness before breeding for low RFOs content. In addition, the presence of multiple copies of GOLs genes in other species suggests the possibility to reduce RFOs only in seeds keeping intact their content in other plant tissues. Here, we report a study of Galactinol Synthase (GOLS) genes, a key enzyme involved in the RFOs synthesis. The phylogenetic study of GOLS genes from several plant species, obtained from the EST database of The Gene Index Project, allowed us grouping the leguminous species in eight subgroups. Eight sets of degenerated primers, developed in base to the subgroups alignments, amplified different GOLS genes in Lupin. The sequence characterization of these novel GOLS sequences will allow us to develop specific primers for the species, determine expression and possible roles of RFOs on plant fitness. We expect to find different copies of GOLS exhibiting tissue-specific-expression on Lupin plants under stress conditions.