The Agrobacterium VirE3 effector protein: a potential plant transcriptional activator.

During the infection of plants, Agrobacterium tumefaciens introduces several Virulence proteins including VirE2, VirF, VirD5 and VirE3 into plant cells in addition to the T-DNA. Here, we report that double mutation of virF and virE3 leads to strongly diminished tumor formation on tobacco, tomato and sunflower. The VirE3 protein is translated from a polycistronic mRNA containing the virE1, virE2 and virE3 genes, in Agrobacterium.

Analysis of Vir protein translocation from Agrobacterium tumefaciens using Saccharomyces cerevisiae as a model: evidence for transport of a novel effector protein VirE3.

Agrobacterium tumefaciens causes crown gall disease on a variety of plants. During the infection process Agrobacterium transfers a nucleoprotein complex, the VirD2 T-complex, and at least two Vir proteins, VirE2 and VirF, into the plant cell via the VirB/VirD4 type IV secretion system. Recently, we found that T-DNA could also be transferred from Agrobacterium to Saccharomyces cerevisiae.