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Dynamic changes in chromatin accessibility and nucleosome positioning in the control of antigen receptor rearrangement

ABSTRACT: Dynamic changes in chromatin accessibility and nucleosome positioning in the control of antigen receptor rearrangement

PROVIDER: PRJNA546258 | ENA |

REPOSITORIES: ENA

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			Action	DRS
	SRR9200770_1.fastq.gz	Fastqsanger.gz
	SRR9200770_2.fastq.gz	Fastqsanger.gz
	SRR9200780_1.fastq.gz	Fastqsanger.gz
	SRR9200780_2.fastq.gz	Fastqsanger.gz
	SRR9200790_1.fastq.gz	Fastqsanger.gz

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Dynamic changes in chromatin accessibility and nucleosome positioning in the control of antigen receptor rearrangement

Project description:Developing lymphocytes diversify their antigen receptor (AgR) loci by V(D)J recombination. Here, we use a low-input version of the MACC (MNase Accessibility) assay to define the chromatin accessibility landscape of primary cells during lymphoid development tracking the changes as different AgR loci become primed for recombination. Distinct chromatin structures define unique features of IgH, Igk and TCRα loci. In particular, we find locus-specific temporal changes in accessibility both across megabase-long AgR loci and locally at the recombination signal sequences (RSSs). These changes appear to be regulated independently. We further identify local dynamic rearrangements of individual nucleosomes at RSSs during B-cell commitment. As predicted by the original “accessibility” hypothesis, these changes correlate with AgR lymphoid lineage and developmental-stage specificity. We suggest that local and global changes in chromatin openness, in concert with nucleosome occupancy and histone modifications, represent additional regulatory layers for governing the temporal order of AgR recombination.

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