Abstract for Botany Conference, 2012
Proteome of pollination drops of four species of Ephedra (Gnetales)
Hou, Chen1 Prior, Natalie2 Bolinder, Kristina1,Rydin, Catarina1 von Aderkas, Patrick2
1 Stockholm University, Botany, Lilla Frescativägen 5, Stockholm, SE-106 91, Sweden 2 University of Victoria, Centre for Forest Biology, Department of Biology, Victoria, BC, V8W 3N5, Canada
Proteins in pollination drops have a range of functions including ovule defense against microbes and pathogens. To study protein and peptide composition in Ephedra (Gnetales), we tested the pollination drops of four species: E. distachya, E. foeminea, E. likiangensis and E. minuta by using 1D SDS-PAGE and a ThermoScientific LTQ Orbitrap. The results reveal that fewer proteins were detected in Ephedra compared with drops of other gymnosperms genera, such as the protein rich Pinidae. Some proteins were detected in E. distachya and E. foeminea whereas in E. likiangensis or E. minuta proteins were almost absent. The low concentration of defense proteins in these pollination drops may be related to the high sucrose content in Ephedra drops. High sugar content brings an elevated osmolarity in Ephedra drops, which may be sufficient to prevent microbial growth in the ovule. The proteomic exploitation of pollination drops in gymnosperms provides a new perspective and potentially some clues to resolve the seed plant phylogeny.