Characterization of single-cell cis-regulatory elements informs implications for cell differentiation.

Abstract

Cis-regulatory elements (CREs) govern the specific patterns and dynamics of gene expression in cells during development, which are the fundamental mechanisms behind cell differentiation. However, the genomic characteristics of single-cell CREs (scCREs) closely linked to cell differentiation during development remain unclear. To explore this, we systematically analyzed ∼250,000 putative scCREs obtained from snATAC-seq analysis of the developing mouse cerebellum. We found that over 80% of these scCREs show pleiotropic effects, being active in two or more cell types. The pleiotropic degrees of proximal and distal scCREs are positively correlated with the density and diversity of transcription factor (TF) binding motifs and GC content. There is a negative correlation between the pleiotropic degrees of scCREs and their distances to the nearest TSSs, and proximal scCREs display higher relevance strengths than distal ones. Furthermore, both proximal and distal scCREs related to cell differentiation exhibit enhanced sequence-level evolutionary conservation, increased density and diversity of TF binding motifs, elevated GC content, and greater distances from their nearest genes. Together, our findings reveal the general genomic characteristics of putative scCREs and provide insights into the genomic and evolutionary mechanisms by which scCREs regulate cell differentiation during development.