Dataset Information

MYT1L is required for suppressing earlier neuronal development programs in the adult mouse brain

ABSTRACT: In vitro studies indicate the neurodevelopmental disorder gene Myelin Transcription Factor 1 Like (MYT1L) suppresses non-neuronal lineage genes during fibroblast-to-neuron direct differentiation. However, MYT1L’s molecular and cellular functions during differentiation in the mammalian brain have not been fully characterized. Here, we found that MYT1L loss leads to up-regulated deep layer (DL) but down-regulated upper layer (UL) neuron gene expression, corresponding to an increased ratio of DL/UL neurons in mouse cortex. To define potential mechanisms, we conducted Cleavage Under Targets & Release Using Nuclease (CUT&RUN) to map MYT1L binding targets in mouse developing cortex and adult prefrontal cortex (PFC), and to map epigenetic changes due to MYT1L mutation. We found MYT1L mainly binds to open chromatin, but with different transcription factor co-occupancies between promoters and enhancers. Likewise, multi-omic dataset integration revealed that, at promoters, MYT1L loss does not change chromatin accessibility but does increase H3K4me3 and H3K27ac, activating both a subset of earlier neuronal development genes as well as BCL11B, a key regulator for DL neuron development. Meanwhile, we discovered that MYT1L normally represses the activity of neurogenic enhancers associated with neuronal migration and neuronal projection development by closing chromatin structures and promoting removal of active histone marks. Further, we show MYT1L interacts with SIN3B and HDAC2 in vivo, providing potential mechanisms underlying any repressive effects on histone acetylation and gene expression. Overall, our findings provide a comprehensive map of MYT1L binding in vivo and mechanistic insights to how MYT1L facilitates neuronal maturation.

ORGANISM(S): Mus musculus

PROVIDER: GSE222072 | GEO | 2023/03/02

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Normal differentiation and induced reprogramming require the activation of target cell programs and silencing of donor cell programs. In reprogramming, the same factors are often used to reprogram many different donor cell types. As most developmental repressors, such as RE1-silencing transcription factor (REST) and Groucho (also known as TLE), are considered lineage-specific repressors, it remains unclear how identical combinations of transcription factors can silence so many different donor programs. Distinct lineage repressors would have to be induced in different donor cell types. Here we found that the pan neuron-specific transcription factor Myt1-like (Myt1l) exerts its pro-neuronal function by direct repression of many different somatic lineage programs but not the neuronal program during reprogramming and neurogenesis and in primary mouse neurons. The repressive function of Myt1l is mediated by recruitment of a complex containing Sin3b by binding to a previously uncharacterized N-terminal domain. In agreement with its repressive function, the genomic binding sites of Myt1l are similar in neurons and fibroblasts and are preferentially in an open chromatin configuration. The Notch signalling pathway is repressed by Myt1l through silencing of several members, including Hes1. Acute knock-down of Myt1l in the developing mouse brain mimicked a Notch gain-of-function phenotype, suggesting that Myt1l allows newborn neurons to escape Notch activation during normal development. Depletion of Myt1l in primary postmitotic neurons de-repressed non-neuronal programs and impaired neuronal gene expression and function, indicating that many somatic lineage programs are actively and persistently repressed by Myt1l to maintain neuronal identity. It is now tempting to speculate that similar ‘many-but-one’ lineage repressors exist for other cell fates; such repressors, in combination with lineage-specific activators, would be prime candidates for use in reprogramming additional cell types.

Dataset Information

MYT1L is required for suppressing earlier neuronal development programs in the adult mouse brain

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure