Mechanisms of host manipulations by Heterodera cyst nematodes
T. BAUM (1) (1) Department of Plant Pathology and Microbiology; Iowa State University, U.S.A.

Heterodera cyst nematodes are highly evolved obligatory pathogen that induce massive plant cellular reprogramming to establish a syncytial feeding site. Nematode effector proteins play roles in the suppression of plant defense responses as well as the developmental reprogramming of host cells. Consequently, identifying and characterizing effectors to uncover their molecular functions is revealing mechanistic insights into nematode parasitism. Single-cell transcriptomics is aiding the identification of effector repertoires of cyst nematode biotypes and integrated research approaches are uncovering details of effector functions. Examples of our research findings include a documentation of convergence of effectors from very disparate pathogens, the identities of effectors that suppress plant defenses, and a mechanistic view on epigenetic manipulation of host gene expression by a nematode effector. This latter insight was gained by studying the H. schachtii 32E03 effector. This protein interacts and co-localizes with an Arabidopsis histone chaperone and a histone deacetylase, which together have been shown to function as rRNA transcription repressors. In planta expression of 32E03 reduced total plant histone deacetylase activity and lead to a derepression of transcription as a consequence of enhanced histone 3 lysine 9 (H3K9) acetylation. Our work is generating mechanistic understanding of parasitism and targets the development of novel management options.

Abstract Number: C5-1
Session Type: Concurrent