Host interactors of effector proteins of the lettuce downy mildew Bremia lactucae obtained by yeast two-hybrid screening.

Plant pathogenic bacteria, fungi and oomycetes secrete effector proteins to manipulate host cell processes to establish a successful infection. Over the last decade the genomes and transcriptomes of many agriculturally important plant pathogens have been sequenced and vast candidate effector repertoires were identified using bioinformatic analyses. Elucidating the contribution of individual effectors to pathogenicity is the next major hurdle.

Multiple downy mildew effectors target the stress-related NAC transcription factor LsNAC069 in lettuce.

To cause disease in lettuce, the biotrophic oomycete Bremia lactucae secretes potential RxLR effector proteins. Here we report the discovery of an effector-target hub consisting of four B. lactucae effectors and one lettuce protein target by a yeast-two-hybrid (Y2H) screening.

Recognition of lettuce downy mildew effector BLR38 in Lactuca serriola LS102 requires two unlinked loci.

Plant-pathogenic oomycetes secrete effector proteins to suppress host immune responses. Resistance proteins may recognize effectors and activate immunity, which is often associated with a hypersensitive response (HR). Transient expression of effectors in plant germplasm and screening for HR has proven to be a powerful tool in the identification of new resistance genes.

Predominant Golgi Residency of the Plant K/HDEL Receptor Is Essential for Its Function in Mediating ER Retention.

Accumulation of soluble proteins in the endoplasmic reticulum (ER) of plants is mediated by a receptor termed ER RETENTION DEFECTIVE2 (ERD2) or K/HDEL receptor. Using two gain-of-function assays and by complementing loss of function in , we discovered that compromising the lumenal N terminus or the cytosolic C terminus with fluorescent fusions abolishes its biological function and profoundly affects its subcellular localization. Based on the confirmed asymmetrical topology of ERD2, we engineered a new fluorescent ERD2 fusion protein that retains biological activity.

Effector-mediated discovery of a novel resistance gene against Bremia lactucae in a nonhost lettuce species.

Candidate effectors from lettuce downy mildew (Bremia lactucae) enable high-throughput germplasm screening for the presence of resistance (R) genes. The nonhost species Lactuca saligna comprises a source of B. lactucae R genes that has hardly been exploited in lettuce breeding.