The Best Offense Is Someone Else’s Defense

Abstract

Part of the strategy that Agrobacterium uses to attack its host plant cells includes transferring part of its genome into the plant cell’s genome. This DNA transfer event has been effectively used as a tool for plant genetic transformation in the lab. In the natural interaction, Agrobacterium uses a complex of proteins, including both its own and the host’s, to effect the transfer of its DNA into the plant cell nucleus. One of the plant’s proteins, VIP1, was known to function for Agrobacterium DNA transfer, but its use to the host plant was unknown. Djamei et al. have now discovered that the plant’s VIP1 is supposed to function in a pathogen defense cascade. Thus, Agrobacterium derails the plant’s defense response by using one of the plant’s own effectors to carry the bacterial DNA into the plant nucleus. A. Djamei, A. Pitzschke, H. Nakagami, I. Rajh, H. Hirt, Trojan horse strategy in Agrobacterium transformation: Abusing MAPK defense signaling. Science 318 , 453-456 (2007). [Abstract] [Full Text]