Deficiency of the Heterogeneous Nuclear Ribonucleoprotein U locus leads to delayed hindbrain neurogenesis

Abstract

ABSTRACTGenetic variants affectingHeterogeneous Nuclear Ribonucleoprotein U (HNRNPU)have been identified in several neurodevelopmental disorders (NDDs). HNRNPU is widely expressed in the human brain and shows the highest postnatal expression in the cerebellum. Recent studies have investigated the role ofHNRNPUin cerebral cortical development, but the effects ofHNRNPUdeficiency on cerebellar development remain unknown. Here, we describe the molecular and cellular outcomes ofHNRNPUlocus deficiency duringin vitroneural differentiation of patient-derived and isogenic neuroepithelial stem cells with a hindbrain profile. We demonstrate thatHNRNPUdeficiency leads to chromatin remodeling of A/B compartments, and transcriptional rewiring, partly by impacting exon inclusion during mRNA processing. Genomic regions affected by the chromatin restructuring and host genes of exon usage differences show a strong enrichment for genes implicated in epilepsies, intellectual disability, and autism. Lastly, we show that at the cellular level.HNRNPUdownregulation leads to altered neurogenesis and an increased fraction of neural progenitors in the maturing neuronal population. We conclude that,HNRNPUlocus is involved in delayed commitment of neural progenitors to neuronal maturation in cell types with hindbrain profile.