Biology subjects

Neikes, H. K.

Publications and source records attributed to Neikes, H. K..

2 recordsLinked to original sources

bioRxiv2022

ONECUT2 restricts Microfold cell numbers in the small intestine; a multi-omics study

Microfold (M) cells reside in the intestinal epithelium of Peyers patches. Their unique ability to take up and transport antigens from the intestinal lumen to the underlying lymphoid tissue is key in the regulation of the gut-associated immune response. Here, we applied a (single-cell) multi-omics approach to investigate the molecular mechanisms that drive M cell differentiation in mouse small intestinal organoids. We generated a comprehensive profile of chromatin accessibility changes and transcription factor dynamics during in vitro M cell differentiation, allowing us to uncover numerous cell type-specific regulatory elements and associated transcription factors. Single-cell RNA sequencing resulted in the identification of an M cell precursor population. Our new computational tool SCEPIA determined that these precursor cells were characterized by high expression of and motif activity for the transcription factor ONECUT2. Subsequent perturbation experiments revealed that ONECUT2 acts downstream of the RANK/RANKL signalling to support Enterocyte differentiation and restrict M cell lineage specification in vitro and in vivo, thereby regulating mucosal immunity. This study provides a useful blueprint for future investigations of cell fate switches in the intestinal epithelium.

molecular biology↗

bioRxiv2022

Chromatin regulates genome-wide transcription factor binding affinities

Transcription factor binding across the genome is regulated by DNA sequence and chromatin features. However, it is not yet possible to quantify the impact of chromatin context on genome-wide transcription factor binding affinities. Here we report the establishment of a method to determine genome-wide absolute apparent binding affinities of transcription factors to native, chromatinized DNA. Our experiments revealed that DNA accessibility is the main determinant of transcription factor binding in the genome, which largely restricts nanomolar affinity binding of YY1, SP1 and MYC/MAX to promoters, while FOXA1 also interacts with non-promoter elements with high affinity. Furthermore, whereas consensus DNA binding motifs for transcription factors are important to establish very high-affinity binding sites, these motifs are not always strictly required to generate nanomolar affinity interactions in the genome. Finally, we uncovered transcription factor concentration dependent binding to specific gene classes, suggesting transcription factor concentration dependent effects on gene expression and cell fate. Importantly, our method adds a quantitative dimension to transcription factor biology which enables stratification of genomic targets based on transcription factor concentration and prediction of transcription factor binding sites under non-physiological conditions, such as disease associated overexpression of (onco)genes.

genomics↗