Characterization and Expression Profiles of Galaetinol Synthase and Raffinose Synthase in Rubber Tree

Galactinol synthase (GolS) and Raffinose synthase (RS) are key enzymes for the synthesis of Raffinose family oligosaccharides (RFOs) which are widely involved in the growth development and resistances to stresses. To explore the function of HbGolSs and HbRSs during leaf development and tapping period in Hevea brasiliensis, in this study, based on the established library data platform of rubber tree genome, we isolated and identified the family members of HbGolSs and HbRSs , then we analyzed their expression profiles with emphasis through on-line molecular biological tools and PRISM software as well. The results demonstrated that HbGolS1 and HbRS1 were prime member in their separate family, HbGOlS1 was highly expressed in latex and leaf, and with leaf development, its level gradually increased till the ultimate in mature leave, especially, it was dramatically up-regulated by tapping but markedly inhibited by Ethrel treatment; Different from it, HbRS1 was little influenced by tapping or Ethrel treatment although it was specially expressed in latex. Together, this study demonstrated the expression characteristics of HbGolS1 and HbRS1 with leaf development and tapping, which has laid a foundation for further exploring the metabolism of RFOs and their roles in rubber trees.