Chromosomal organization plays a critical role in gene expression and cellular function, with three-dimensional interactions like Topologically Associating Domains (TADs) shaping genome architecture. These TADs are maintained by the cohesin complex, comprising key proteins like RAD21, NIPBL, WAPL, and CTCF, which are involved in chromatin looping and the regulation of genome structure. Mutations in genes encoding these proteins are linked to a variety of disorders, particularly cohesinopathies, including Cornelia de Lange Syndrome (CdLS). In this study, functional genomic techniques were employed to explore the consequences of mutations in genes involved in genome organization. CRISPR-Cas9 was used to generate loss-of-function variants in induced pluripotent stem cells (iPSCs), which were differentiated into neurons to model neurodevelopmental phenotypes observed in patients. Through RNA-seq and Hi-C, the transcriptome and 3D genome structure of these neuronal models were analyzed. It was found that RAD21 mutations caused clonal differentiation abnormalities, supporting the hypothesis of altered 3D genome structure rather than aneuploidy. Mild decreases in gene expression at the RNA and protein levels for NIPBL and CTCF mutations were also observed, which mirrored patient data. A comprehensive literature search and database mining revealed large  variability in differentially expressed genes (DEGs) across cell types and experiments involving cohesin perturbation, highlighting the complexity of cohesin-related diseases. While statistical analyses and additional data are ongoing, this work aims to establish a detailed pathophysiological framework for cohesinopathies by comparing DEGs in various models and analyzing the impact of altered genome architecture on neurodevelopmental processes.

For more information: mjmccune@eckerd.edu

Accessibility | Non-Discrimination | Privacy | Report It