Molecular Analysis of the role of a yeast potassium transport component TRK1 in Agrobacterium-Mediated transformation

Abstract

Agrobacterium tumefaciens is a commonly used tool in molecular biology research with the ability of transferring DNA to eukaryote cells. One of the eukaryote models that have been extensively used for research in host factors affecting agrobacterium-mediated transformation is yeast Saccharomyces cerevisiae. Potassium transport is an essential activity in cell growth not only in yeast but also in all other organism and the relation with Agrobacterium-mediated transformation has not been clear. We have found that the major high affinity potassium uptake Trk1 in yeast played a significant role in Agrobacterium-mediated transformation process. There was no transformant detected from Trk1 deletion strain while the recombinant strains showed the recovery of transformation efficiency. It suggested that Trk1p had an important positive effect on Agrobacterium-mediated transformation. Data from trk1p regulators also supported the hypothesis. Moreover, we also found that the potassium ion concentration also have impact to Agrobacterium-mediated transformation, suggesting that the defection of potassium uptake influenced the transformation efficiency. However, since the T-DNAs were detected in trk1 deletion strain in early stages of transformation process, the mechanism of trk1p affecting transformation was still unclear. We suggested that the deletion of Trk1 caused effect in T-DNA trafficking stages of Agrobacterium-mediated transformation.