Histone modification dynamics at H3K27 are associated with altered transcription of < i > in planta < /i > induced genes in < i > Magnaporthe oryzae < /i >

by Wei Zhang, Jun Huang, David E. Cook Transcriptional dynamic in response to environmental and developmental cues are fundamental to biology, yet many mechanistic aspects are poorly understood. One such example is fungal plant pathogens, which use secreted proteins and small molecules, termed effectors, to suppress host immunity and p romote colonization. Effectors are highly expressedin planta but remain transcriptionally repressedex planta, but our mechanistic understanding of these transcriptional dynamics remains limited. We tested the hypothesis that repressive histone modification at H3-Lys27 underlies transcriptional silencingex planta, and that exchange for an active chemical modification contributes to transcription ofin planta induced genes. Using genetics, chromatin immunoprecipitation and sequencing and RNA-sequencing, we determined that H3K27me3 provides significant local transcriptional repression. We detail how regions that lose H3K27me3 gain H3K27ac, and these changes are associated with increased transcription. Importantly, we observed that manyin planta induced genes were marked by H3K27me3 during axenic growth, and detail how altered H3K27 modification influences transcription. ChIP-qPCR duringin planta growth suggests that H3K27 modifications are generally stable, but can undergo dynamics at specific genomic locations. Our results support the hypothesis that dynamic histone modifications at H3K27 contributes to fungal genome regulation and specifically c...
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research