Abstract
Recently, it has been reported that various environmental stresses induce galactinol synthase genes (GolS) and accumulation of raffinose-related oligosaccharides leading to aquired tolerance in Arabidopsis and tomato (Yuasa et al., this meeting, 2009). Our previous studies indicated that reactive oxygen species (ROS) treatment appeared to improve drought tolerance of soybean. So, we investigated expression profiles of GmGolS in soybean under drought and phytophrmonal signals involving GmGolS. Semi-quantitative RT-PCR indicated that GmGolS and ethylene signaling genes, GmACS and GmERF, were induced in response to drought treatment. GmGolS, GmACS and GmERF were induced by hydroperoxide. Furthermore, immunoblot with anti-Ein3 specific antibody revealed that drought and hydroperoxid treatments on soybean up-regulated a protein level of Ein3 homolog, which is known to be involved in ethylene-dependent induction of ERF. These results suggested that induction of GmGolS in soybean under drought is involved in ROS and ethylene signal.
