Figure 1.

Experimental strategy to detect Vir protein translocation from Agrobacterium into yeast. The yeast cells contain a lox-URA3-lox marker integrated at the PDA locus. Upon co-cultivation with acetosyringone (AS)-induced Agrobacterium cells expressing Cre-Vir fusion protein (see Materials and Methods) for 6 days the mixture of cells is plated on medium supporting yeast growth and containing FOA. Delivery of a functional Cre enzyme from Agrobacterium into yeast is detected by Cre-mediated site-specific recombination on the lox sites resulting in loss of the URA3 gene allowing growth on medium containing FOA. Part of the mixture is used to determine the output of Agrobacterium and yeast cells (see Materials and Methods). Black triangles, Agrobacterium left and right border sequences.