Polycomb Group (PcG) proteins are part of an epigenetic cell memory system that plays essential roles in multicellular development, stem cell biology, X chromosome inactivation, and cancer. In animals, plants, and many fungi, Polycomb Repressive Complex 2 (PRC2) catalyzes trimethylation of histone H3 lysine 27 (H3K27me3) to assemble transcriptionally repressed facultative heterochromatin. PRC2 is structurally and functionally conserved in the model fungus
Chromatin accessibility profiling in Neurospora crassa reveals molecular features associated with accessible and inaccessible chromatin
Abstract Background Regulation of chromatin accessibility and transcription are tightly coordinated processes. Studies in yeast and higher eukaryotes have described accessible chromatin regions, but little work has been done in filamentous fungi. Results Here we present a genome-scale characterization of accessible chromatin regions in Neurospora crassa , which revealed characteristic molecular features of accessible and inaccessible chromatin. We present experimental evidence of inaccessibility within heterochromatin regions in Neurospora, and we examine features of both accessible and inaccessible chromatin, including the presence of histone modifications, types of transcription, transcription factor binding, and relative nucleosome turnover rates. Chromatin accessibility is not strictly correlated with expression level. Accessible chromatin regions in the model filamentous fungus Neurospora are characterized the presence of H3K27 acetylation and commonly associated with pervasive non-coding transcription. Conversely, methylation of H3 lysine-36 catalyzed by ASH1 is correlated with inaccessible chromatin within promoter regions. Conclusions: In N. crassa, H3K27 acetylation is the most predictive histone modification for open chromatin. Conversely, our data show that H3K36 methylation is a key marker of inaccessible chromatin in gene-rich regions of the genome. Our data are consistent with an expanded role for H3K36 methylation in intergenic regions of filamentous fungi compared to the model yeasts, more »
- Award ID(s):
- 1856627
- Publication Date:
- NSF-PAR ID:
- 10321581
- Journal Name:
- BMC Genomics
- Volume:
- 22
- Issue:
- 1
- ISSN:
- 1471-2164
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.1186/s12864-021-07774-0
