Novel viral strategy for evading RNA silencing

Viral protein blocks RNA silencing in Arabidopsis by inhibiting Argonaute1

Jeffrey M. Perkel
Nov 30, 2006
Researchers have uncovered a novel viral strategy for evading RNA silencing in plants, according to a report in Genes & Development. Nam-Hai Chua, the Andrew W. Mellon Professor and head of the plant molecular biology laboratory at Rockefeller University, and colleagues demonstrate both in Arabidopsis and in vitro that the cucumber mosaic virus (CMV) protein 2b binds to and inhibits Argonaute1, thereby circumventing the plant's antiviral response. Though other viral suppressors of RNA silencing had previously been identified, this is the first to be shown to clearly bind an effector protein in the silencing pathway. "I think it's a beautiful lesson in how you conceptualize this 'arms race' between pathogen and host," said James Carrington, director of the Center for Genome Research and Biocomputing at Oregon State University, who also studies viral suppressor proteins. "Imagine this as a battlefield where on one side you have the host...