Postdoctoral fellow Dr. Daolong Dou, the lead author of the article, commented: "We have suspected for a long time that these virulence proteins had some way of slipping inside plant cells to suppress immunity. Our findings finally nail down that mechanism and enable us to focus on how to block the entry mechanism."
The researchers also demonstrated that the RXLR and dEER motifs could be replaced by similar targeting sequences found in effector proteins produced by the malarial parasite Plasmodium. This hints that the targets of the effectors in the soybean and human hosts may be very ancient.
VBI Professor Brett Tyler remarked: "The finding that virulence proteins from oomycetes and the malaria parasite Plasmodium use the same entry mechanism means that we may be able to use the same or similar drugs to block infection by both groups of pathogens. This type of approach may also be relevant to other groups of pathogens, such as fungi, which we also suspect of slipping virulence proteins into host cells."
The breakthrough was enabled by an ingenious device for introducing DNA into living tissues invented by a Virginia Tech undergraduate, Shiv Kale. Kale, who has subsequently joined Dr. Tyler's research team as a graduate student, remarked: "The double-barreled Gene Gun enabled us to make much more accurate measurements of the Avr1b protein than were previously possible, which made it practicable to measure the action of the RXLR and dEER motifs." Kale was co-lead author of the article.
|Contact: Barry Whyte|