Overexpression of XXXX BAX inhibitor 1 induces breakdown of mlo-mediated penetration resistance to Blumeria graminis.

@entity1 @entity10327 @entity20729 @entity2247 @entity364 @entity30363
Cell death regulation is linked to pathogen defense in plants and animals. Execution of apoptosis as one type of programmed cell death in animals is irreversibly triggered by cytochrome c release from mitochondria via pores formed by BAX proteins. This type of programmed cell death can be prevented by expression of BAX inhibitor 1 ( @entity30363 ), a membrane protein that protects cells from the effects of BAX by an unknown mechanism. In @entity2247 , a homologue of the @entity1 @entity30363 is expressed in response to inoculation with the @entity2247 powdery mildew fungus Blumeria graminis @entity10327 . hordei (Bgh). We found differential expression of @entity30363 in response to Bgh in susceptible and resistant plants. Chemical induction of resistance to Bgh by soil drench treatment with @entity20729 led to down-regulation of the expression level of @entity30363 . Importantly, single-cell transient overexpression of @entity30363 in epidermal leaf tissue of susceptible @entity2247 cultivar Ingrid led to enhanced accessibility, resulting in a higher penetration efficiency of Bgh on @entity30363 -transformed cells. In Bgh-resistant mlo5 genotypes, which do not express the negative regulator of defense and cell death MLO, overexpression of @entity30363 almost completely reconstituted susceptibility to fungal penetration. We suggest that @entity30363 is a regulator of cellular defense in @entity2247 sufficient to substitute for MLO function in accessibility to @entity364 .
