Putative CalS5 orthologue (CcCalS5) topology and expression in Cabomba caroliniana and Nymphaea odorata. A, Predicted topology for CcCalS5 isolated from Cabomba pollen. Numbers indicate predicted amino acids in each domain. B, Semi-quantitative RT-PCR. Gels on left are from Cabomba cDNA derived from different tissues: S-stem tissue, L-leaf tissue, M-meristem tissue, A-pre-dehiscent anther and pollen, P-mature pollen grains. Gels on right are from Nymphaea cDNA: G-genomic DNA control, 0-mature pollen stage, 1, 3 and 6-pollen tubes at 1, 3 and 6 h post-inoculation.