Tanackovic, Vanja2; Svensson, Jan Tommy3; Glaring, Mikkel Andreas4; Carciofi, Massimiliano6; Blennow, Per Gunnar Andreas5
1 Department of Molecular Biology and Genetics - Afgrødegenetik og Bioteknologi, Department of Molecular Biology and Genetics, Science and Technology, Aarhus University2 Institut for Plantebiologi og Bioteknologi3 Planteglykobiologi4 Genetik og Mikrobiologi5 Molekylær Plantebiologi6 Department of Molecular Biology and Genetics - Afgrødegenetik og Bioteknologi, Department of Molecular Biology and Genetics, Science and Technology, Aarhus University
Brachypodium distachyon was recently introduced as a model plant for temperate cereals (Opanowicz et al., 2008). We aim to establish Brachypodium as a model for cereal starch metabolism. Grain starch from two lines: Bd21 and Bd21-3 are being characterized. Microscopic, chemical and structural data including amylopectin chain length distribution, phosphate content and amylose content provided further evidence for the close relationship to temperate cereals even though starch content and starch granule size were considerably lower than that for barley (Hordeum vulgare). Bioinformatics analyses identified starch biosynthesis genes including seven soluble starch synthases (SS), three granule bound starch syntheses (GBSS), four starch branching enzymes (SBE), two glucan- and one phosphoglucan- water dikinases (GWD, PWD). Phylogenetic analysis based on the SS genes provided evidence for a close relation to barley and wheat. Putative carbohydrate-binding modules (CBMs) of the families CBM20, CBM45, SBM48 and BM53 were identified and the positions of these were conserved. Based on these preliminary data we suggest that Brachypodium distachyon can provide a valuable model for starch bioengineering in temperate cereals.