Phosphate transporter expression in the soybean AM symbiosis

Abstract

We are currently studying genes that are potentially involved in the process of phosphate uptake in the arbuscular mycorrhizal (AM) symbiosis of soybean. We have extracted mRNA from AM colonised and uncolonised soybean roots using biotinylated poly-T probes and streptavidin-coated magnetic particles. Total mRNA extracted by this method was reverse-transcribed into cDNA with poly-T primer and reverse transcriptase. cDNA was next PCR-amplified with primers for a previously published soybean root phosphate transporter gene and amplified sequences were visualized on silver-stained acrylamide gels. In situ hybridization studies were carried out to localise the phosphate transporter in root tissues. Root cryosections were probed with a fluorosceinconjugated antisense probe and bound targets were visualized either via alkaline phosphatase labeling or with an antifluoroscein texas-red antibody. Results of these investigations are presented here.