Plant response to bacterial pathogens. Overlap between innate and gene-for-gene defense response.

The immune system’s role as defense from opportunistic microbes also necessitated the ability to distinguish between ‘‘self’’ and ‘‘non-self’’ to ensure that an immune response is not mounted against the organism’s own tissues. This discrimination is partially achieved by the recognition of an invader’s chemical motifs by host surface receptors. Consequently, potential pathogens have adapted numerous ways to overcome host immune systems while the hosts respond with new defenses. In plants, this ongoing ‘‘battle’’ against pathogens has led to two types of immune responses: an older, basal response to pathogenassociated molecular patterns (PAMPs) and a genefor-gene response specific to a pathogen. This month’s selection for High Impact examines the immune response of Arabidopsis (Arabidopsis thaliana) to one such PAMP and the interaction between the two immune responses. The article is ‘‘The Transcriptional Innate Immune Response to flg22. Interplay and Overlap with Avr Gene-Dependent Defense Responses and Bacterial Pathogenesis’’ by Lionel Navarro, Cyril Zipfel, Owen Rowland, Ingo Keller, Silke Robatzek, Thomas Boller, and Jonathan D.G. Jones. It appeared in our June 2004 issue in the section ‘‘Plants Interacting with Other Organisms.’’ As of September 2006, it had been cited 35 times according to Thompson ISI (Thompson ISI Web of Science, http://www.isinet.com).