Abstract
Recent studies indicate that raffinose-related oligosaccharides are synthesized in response to various stresses, salt stress and drought in higher plants and that the oligosaccharides play important roles in protection of proteins and biomembranes as osmolytes and antioxidants. The raffinose-related oligosaccharides are synthesized by galactinol synthase (GolS) with UDP-galactose and myo-inositol. In Arabidopsis, a GolS gene is expressed in seed and multiple GolSs are differentially regulated in plant under drought, salt stress and chilling. We isolated a full length cDNA of galactinol synthase (SlGolS2) in tomato (Solanum lycopersicum L. cv. Micro-Tom), based on partial sequences of GolS homologs in MiBASE (Kazusa DNA Institute). SlGolS2 was transiently induced in response to salt, heat and chilling stresses. Involvement of phytohormones and oxidative stress on SlGolS2 expression and characterization of a recombinant SlGolS2 will be discussed.
