Unraveling the role of transcription factor YY1 in B cell lineage commitment: A comprehensive exploration of epigenetic regulation and chromatin architecture

---

Presentation Time: 10:30 AM - 10:45 AM
Abstract ID: 5591 - B

Presenting Author:
Sulagna Sanyal , Postdoctoral Researcher at Univ. of Pennsylvania Sch. of Vet. Med.

Abstract:

Immune cell development relies on intricate transcriptional and epigenetic mechanisms dictating lineage specification. YY1, a transcription factor with dual transcriptional roles, manages lineage-specific chromatin interactions despite its ubiquitous expression. In, our study, conditional YY1 knock-out in the B cell lineage resulted in the loss of B-lineage commitment. Remarkably, YY1-null pro-B cells exhibited a proclivity to differentiate into T-cell lineage cells both in vitro and in vivo. To understand YY1-mediated lineage commitment mechanisms, we study YY1's influence on LRCIs, genomic changes, and lineage-specific heterochromatic structures. Using high-throughput Next Generation sequencing, we perform ATAC-seq and Hi-C analyses in wild-type and YY1-null pro-B cells. We compare these datasets with transcriptomic and epigenomic profiles of respective pro-B cells. Comprehensive analyses uncovered profound alterations in chromatin structures between wild-type and YY1-null pro-B cells. Our hypothesis proposes that YY1 depletion disrupts LRCIs crucial for stabilizing B lineage gene expression while alleviating YY1's repressive effect on alternative lineage genes. Our ongoing research aims to further investigate this distinctive YY1-mediated regulation through comprehensive comparative analyses. These efforts unveiled the complex mechanisms governing YY1's involvement in immune cell lineage determination.