Assays for effector-mediated suppression of programmed cell death in yeast.

Pathogens such as bacteria, fungi, and oomycetes deliver diverse arrays of virulence or avirulence molecules, defined here as effectors, into the host cells. Effectors enable parasitic colonization by manipulating classes of biochemical, physiological, and morphological processes. An effective strategy to modulate host defense circuitry is to suppress their programmed cell death (PCD) response. Here, we describe a method for analyzing whether effectors function to suppress PCD in yeast. We use Bax and H(2)O(2) to induce cell death and mimic some PCD features that naturally appear during the development of multicellular Saccharomyces cerevisiae colonies and assay whether plant pathogen effectors can inhibit the process. This technology provides an assay to test whether individual effectors can suppress PCD.