Pliego, ClaraNowara, DanielaBonciani, GiuliaGheorghe, DanaXu, RuoSurana, PriyankaWhigham, EhrenNettleton, DanielBogdanove, AdamWise, RogerSchweizer, PatrickBindschedler, LaurenceSpanu, Pietro2020-07-022020-07-022013-06-01https://dr.lib.iastate.edu/handle/20.500.12876/90641<p>Obligate biotrophic pathogens of plants must circumvent or counteract defenses to guarantee accommodation inside the host. To do so, they secrete a variety of effectors that regulate host immunity and facilitate the establishment of pathogen feeding structures called haustoria. The barley powdery mildew fungus <em>Blumeria graminis</em> f. sp. <em>hordei</em>produces a large number of proteins predicted to be secreted from haustoria. Fifty of these <em>Blumeria</em> effector candidates (BEC) were screened by host-induced gene silencing (HIGS), and eight were identified that contribute to infection. One shows similarity to β-1,3 glucosyltransferases, one to metallo-proteases, and two to microbial secreted ribonucleases; the remainder have no similarity to proteins of known function. Transcript abundance of all eight BEC increases dramatically in the early stages of infection and establishment of haustoria, consistent with a role in that process. Complementation analysis using silencing-insensitive synthetic cDNAs demonstrated that the ribonuclease-like BEC 1011 and 1054 are bona fide effectors that function within the plant cell. BEC1011 specifically interferes with pathogen-induced host cell death. Both are part of a gene superfamily unique to the powdery mildew fungi. Structural modeling was consistent, with BEC1054 adopting a ribonuclease-like fold, a scaffold not previously associated with effector function.</p>application/pdfenarticleisulib-bepress-aws-west10427912077stat_las_pubs/43Agricultural ScienceAgricultureBioinformaticsBiostatisticsComputational BiologyMicrobiologyPlant Pathology