Gavin Kelsey

Research Summary

As well as genetic information, the egg and sperm also contribute epigenetic annotations that may influence gene activity after fertilisation. These annotations may be direct modifications of the DNA bases or of the proteins around which the DNA is wrapped into chromatin. Our goal is to understand whether, through epigenetics, factors such as a mother’s age or diet have consequences on the health of a child.
 
We examine how epigenetic states are set up in oocytes – or egg cells – and influence gene expression in the embryo. For example, repressive chromatin marks in oocytes lead to long-term silencing of genes inherited from the mother, particularly in cells that will form the placenta. We are also interested in how variations in DNA methylation come about in oocytes and whether we can use this variation as a marker for oocyte quality and embryo potential. To investigate these questions, we develop methods to profile epigenetic information in very small numbers of cells or even in single cells.

Latest Publications

Profiling DNA Methylation Genome-Wide in Single Cells.
Galvão A, Kelsey G

Single-cell bisulfite sequencing (scBS-seq) enables profiling of DNA methylation at single-nucleotide resolution and across all genomic features. It can explore methylation differences between cells in mixed cell populations and profile methylation in very rare cell types, such as mammalian oocytes and cells from early embryos. Here, we outline the scBS-seq protocol in a 96-well plate format applicable to studies of moderate throughput.

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Methods in molecular biology (Clifton, N.J.), 2214, 1, 2021

PMID: 32944913

Tumor Necrosis Factor α Influences Phenotypic Plasticity and Promotes Epigenetic Changes in Human Basal Forebrain Cholinergic Neuroblasts.
Guarnieri G, Sarchielli E, Comeglio P, Herrera-Puerta E, Piaceri I, Nacmias B, Benelli M, Kelsey G, Maggi M, Gallina P, Vannelli GB, Morelli A

TNFα is the main proinflammatory cytokine implicated in the pathogenesis of neurodegenerative disorders, but it also modulates physiological functions in both the developing and adult brain. In this study, we investigated a potential direct role of TNFα in determining phenotypic changes of a recently established cellular model of human basal forebrain cholinergic neuroblasts isolated from the nucleus basalis of Meynert (hfNBMs). Exposing hfNBMs to TNFα reduced the expression of immature markers, such as nestin and β-tubulin III, and inhibited primary cilium formation. On the contrary, TNFα increased the expression of TNFα receptor TNFR2 and the mature neuron marker MAP2, also promoting neurite elongation. Moreover, TNFα affected nerve growth factor receptor expression. We also found that TNFα induced the expression of DNA-methylation enzymes and, accordingly, downregulated genes involved in neuronal development through epigenetic mechanisms, as demonstrated by methylome analysis. In summary, TNFα showed a dual role on hfNBMs phenotypic plasticity, exerting a negative influence on neurogenesis despite a positive effect on differentiation, through mechanisms that remain to be elucidated. Our results help to clarify the complexity of TNFα effects in human neurons and suggest that manipulation of TNFα signaling could provide a potential therapeutic approach against neurodegenerative disorders.

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International journal of molecular sciences, 21, 17, 25 Aug 2020

PMID: 32854421

Imprints in the history of epigenetics.
Kelsey G

No abstract available

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Nature reviews. Molecular cell biology, 1, 1, 24 Aug 2020

PMID: 32839539