Journal article

Publication year: 2003

Pages: 5555-5560

Journal: Proceedings of the National Academy of Sciences

Volume number: 100

Issue number: 9

ISSN: 0027-8424

Open access status: Green

DOI Link: https://doi.org/10.1073/pnas.0931464100

Publisher: National Academy of Sciences

Abstract: 
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 mitochonchria via pores formed by BAX proteins. This type of programmed cell death can be prevented by expression of BAX inhibitor (BI-1), a membrane protein that protects cells from the effects of BAX by an unknown mechanism. In barley, a homologue of the mammalian BI-1 is expressed in response to inoculation with the barley powdery mildew fungus Blumeria graminis f.sp. hordei (Bgh). We found differential expression of BI-1 in response to Bgh in susceptible and resistant plants. Chemical induction of resistance to Bgh by soil drench treatment with 2,6-dichloroisonicotinic acid led to down-regulation of the expression level of BI-1. Importantly, single-cell transient overexpression of BI-1 in epidermal leaf tissue of susceptible barley cultivar Ingrid led to enhanced accessibility, resulting in a higher penetration efficiency of Bgh on BI-1-transformed cells. In Bgh-resistant mloS genotypes, which do not express the negative regulator of defense and cell death MLO, overexpression of BI-1 almost completely reconstituted susceptibility to fungal penetration. We suggest that BI-1 is a regulator of cellular defense in barley sufficient to substitute for MLO function in accessibility to fungal parasites.

Harvard Citation style: Hückelhoven, R., Dechert, C. and Kogel, K. (2003) Overexpression of barley BAX inhibitor 1 induces breakdown of mlo-mediated penetration resistance to Blumeria graminis, Proceedings of the National Academy of Sciences, 100(9), pp. 5555-5560. https://doi.org/10.1073/pnas.0931464100

APA Citation style: Hückelhoven, R., Dechert, C., & Kogel, K. (2003). Overexpression of barley BAX inhibitor 1 induces breakdown of mlo-mediated penetration resistance to Blumeria graminis. Proceedings of the National Academy of Sciences. 100(9), 5555-5560. https://doi.org/10.1073/pnas.0931464100