Biology subjects

Paslawski, W.

Publications and source records attributed to Paslawski, W..

2 recordsLinked to original sources

bioRxiv2022

Single cell transcriptomics reveals correct developmental dynamics and high-quality midbrain cell types by improved hESC differentiation.

Stem cell technologies provide new opportunities for modeling cells in the healthy and diseased states and for regenerative medicine. In both cases developmental knowledge as well as the quality and molecular properties of the cells are essential for their future application. In this study we identify developmental factors important for the differentiation of human embryonic stem cells (hESCs) into midbrain dopaminergic (mDA) neurons. We found that Laminin-511, and dual canonical and non-canonical WNT activation followed by GSK3{beta} inhibition plus FGF8b, improved midbrain patterning. In addition, mDA neurogenesis and differentiation was enhanced by activation of liver X receptors and inhibition of fibroblast growth factor signaling. Moreover, single-cell RNA-sequencing analysis revealed a developmental dynamics similar to that of the endogenous human ventral midbrain and the emergence of high quality molecularly-defined midbrain cell types, including mDA neurons that become functional. Thus, our study identifies novel factors important for human midbrain development and opens the door for a future application of molecularly-defined hESC-derived midbrain cell types in Parkinsons disease.

neuroscience↗

bioRxiv2022

PRC2-mediated repression is essential to maintain identity and function of differentiated dopaminergic and serotonergic neurons

How neurons in the CNS can maintain cellular identity over an entire lifespan remains largely unknown. Here we show that long-term maintenance of identity in differentiated dopaminergic and serotonergic neurons is critically reliant on the Polycomb repressive complex 2 (PRC2). Deletion of the obligate PRC2-component, Eed, in these neurons, resulted in global loss of H3K27me3, followed by a gradual activation of genes harbouring both H3K27me3 and H3K9me3 modifications. Notably, H3K9me3 was also lost at these PRC2-targets prior to gene activation. Neuronal survival was not compromised, instead there was a reduction in subtype specific gene expression as well as a progressive impairment of dopaminergic or serotonergic neuronal function leading to behavioural deficits characteristic of Parkinsons disease (PD) or mood disorders, respectively. Single cell analysis revealed an unexpected subtype specific vulnerability to loss of PRC2-repression in dopamine neurons of the substantia nigra, the neurons primarily affected in PD. Taken together, our study reveals that a PRC2-dependent non-permissive chromatin state is essential to maintain subtype identity and function of dopaminergic and serotonergic neurons.

neuroscience↗