Life Sciences Research for Lifelong Health

Stefan Schoenfelder

Dr Schoenfelder holds a Babraham Institute Career Progression Fellowship which provides two years of support for his research.

Research Summary

Functional organisation of the genome in 3D
98% of the DNA in our body is non-coding, i.e. does not carry the information needed to build proteins. Non-coding has sometimes been equated with ‘non-functional’, or called ‘junk’ in the past; today we know that this is far from the truth. Scattered throughout non-coding DNA is a plethora of so-called regulatory elements, including enhancers, silencers and insulators. These regulatory elements function like molecular switches to control which genes are active (and thus produce proteins) in which cells. This process of gene expression control is vital to allow cells – which all contain the same genes – to specialise to carry out different tasks, and to help them respond to changes.

Enhancers are a type of regulatory element that control gene expression over long distances. They contact their target genes via chromosomal interactions, often bridging large distances in the genome, with the intervening DNA ‘looping out’. To understand how enhancers work, we study them in the context of the three-dimensional organisation of the genome.
 
Our aim is to find regulatory elements and to understand which genes they control. We also aim to uncover the molecular mechanisms by which regulatory elements find their target genes in the three-dimensional space of the cell nucleus, and to understand how altering the function of regulatory elements can lead to developmental malformations and disease.
 
We study these questions in pluripotent stem cells – cells that have the potential to create all cell types in the adult body. We use a combination of molecular, genetic, biochemical and imaging approaches to study pluripotent stem cells in their ‘ground state’, and when they start to form new cell types – a process called cell lineage specification.
 
Techniques and Methods

Through high-resolution mapping and experimental perturbation of the spatial genome architecture, we aim to reveal gene regulatory principles that underpin cell states and cell fate transitions. This may ultimately pave the way for us to experimentally engineer 3D genome folding to achieve predictable outcomes on gene expression and cell fate choice, with potential implications for gene therapy and regenerative medicine.
 

Latest Publications

Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions.
Schoenfelder S, Javierre BM, Furlan-Magaril M, Wingett SW, Fraser P

The three-dimensional organization of the genome is linked to its function. For example, regulatory elements such as transcriptional enhancers control the spatio-temporal expression of their target genes through physical contact, often bridging considerable (in some cases hundreds of kilobases) genomic distances and bypassing nearby genes. The human genome harbors an estimated one million enhancers, the vast majority of which have unknown gene targets. Assigning distal regulatory regions to their target genes is thus crucial to understand gene expression control. We developed Promoter Capture Hi-C (PCHi-C) to enable the genome-wide detection of distal promoter-interacting regions (PIRs), for all promoters in a single experiment. In PCHi-C, highly complex Hi-C libraries are specifically enriched for promoter sequences through in-solution hybrid selection with thousands of biotinylated RNA baits complementary to the ends of all promoter-containing restriction fragments. The aim is to then pull-down promoter sequences and their frequent interaction partners such as enhancers and other potential regulatory elements. After high-throughput paired-end sequencing, a statistical test is applied to each promoter-ligated restriction fragment to identify significant PIRs at the restriction fragment level. We have used PCHi-C to generate an atlas of long-range promoter interactions in dozens of human and mouse cell types. These promoter interactome maps have contributed to a greater understanding of mammalian gene expression control by assigning putative regulatory regions to their target genes and revealing preferential spatial promoter-promoter interaction networks. This information also has high relevance to understanding human genetic disease and the identification of potential disease genes, by linking non-coding disease-associated sequence variants in or near control sequences to their target genes.

+ View Abstract

Journal of visualized experiments : JoVE, , 1940-087X, , 2018

PMID: 30010637

Long-Range Enhancer Interactions Are Prevalent in Mouse Embryonic Stem Cells and Are Reorganized upon Pluripotent State Transition.
Novo CL, Javierre BM, Cairns J, Segonds-Pichon A, Wingett SW, Freire-Pritchett P, Furlan-Magaril M, Schoenfelder S, Fraser P, Rugg-Gunn PJ

Transcriptional enhancers, including super-enhancers (SEs), form physical interactions with promoters to regulate cell-type-specific gene expression. SEs are characterized by high transcription factor occupancy and large domains of active chromatin, and they are commonly assigned to target promoters using computational predictions. How promoter-SE interactions change upon cell state transitions, and whether transcription factors maintain SE interactions, have not been reported. Here, we used promoter-capture Hi-C to identify promoters that interact with SEs in mouse embryonic stem cells (ESCs). We found that SEs form complex, spatial networks in which individual SEs contact multiple promoters, and a rewiring of promoter-SE interactions occurs between pluripotent states. We also show that long-range promoter-SE interactions are more prevalent in ESCs than in epiblast stem cells (EpiSCs) or Nanog-deficient ESCs. We conclude that SEs form cell-type-specific interaction networks that are partly dependent on core transcription factors, thereby providing insights into the gene regulatory organization of pluripotent cells.

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Cell reports, 22, 2211-1247, 2615-2627, 2018

PMID: 29514091

Thrombopoietin signaling to chromatin elicits rapid and pervasive epigenome remodeling within poised chromatin architectures.
Comoglio F, Park HJ, Schoenfelder S, Barozzi I, Bode D, Fraser P, Green AR

Thrombopoietin (TPO) is a critical cytokine regulating hematopoietic stem cell maintenance and differentiation into the megakaryocytic lineage. However, the transcriptional and chromatin dynamics elicited by TPO signaling are poorly understood. Here, we study the immediate early transcriptional and cis-regulatory responses to TPO in hematopoietic stem/progenitor cells (HSPCs) and use this paradigm of cytokine signaling to chromatin to dissect the relation between cis- regulatory activity and chromatin architecture. We show that TPO profoundly alters the transcriptome of HSPCs, with key hematopoietic regulators being transcriptionally repressed within 30 minutes of TPO. By examining cis-regulatory dynamics and chromatin architectures, we demonstrate that these changes are accompanied by rapid and extensive epigenome remodeling of cis-regulatory landscapes that is spatially coordinated within topologically associating domains (TADs). Moreover, TPO-responsive enhancers are spatially clustered and engage in preferential homotypic intra- and inter-TAD interactions that are largely refractory to TPO signaling. By further examining the link between cis-regulatory dynamics and chromatin looping, we show that rapid modulation of cis-regulatory activity is largely independent of chromatin looping dynamics. Finally, we show that, although activated and repressed cis-regulatory elements share remarkably similar DNA sequence compositions, transcription factor binding patterns accurately predict rapid cis-regulatory responses to TPO.

+ View Abstract

Genome research, , 1549-5469, , 2018

PMID: 29429976

 

Group Members

Latest Publications

Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions.

Schoenfelder S, Javierre BM, Furlan-Magaril M

Journal of visualized experiments : JoVE
1940-087X: (2018)

PMID: 30010637

GOTHiC, a probabilistic model to resolve complex biases and to identify real interactions in Hi-C data.

Mifsud B, Martincorena I, Darbo E

PloS one
12 1932-6203:e0174744 (2017)

PMID: 28379994

Global reorganisation of cis-regulatory units upon lineage commitment of human embryonic stem cells.

Freire-Pritchett P, Schoenfelder S, Várnai C

eLife
6 2050-084X: (2017)

PMID: 28332981

Identifying Causal Genes at the Multiple Sclerosis Associated Region 6q23 Using Capture Hi-C.

Martin P, McGovern A, Massey J

PloS one
11 1932-6203:e0166923 (2016)

PMID: 27861577

Capture Hi-C identifies a novel causal gene, IL20RA, in the pan-autoimmune genetic susceptibility region 6q23.

McGovern A, Schoenfelder S, Martin P

Genome biology
17 1474-760X:212 (2016)

PMID: 27799070

CHiCAGO: robust detection of DNA looping interactions in Capture Hi-C data.

Cairns J, Freire-Pritchett P, Wingett SW

Genome biology
17 1474-760X:127 (2016)

PMID: 27306882

HiCUP: pipeline for mapping and processing Hi-C data.

Wingett S, Ewels P, Furlan-Magaril M

F1000Research
4 2046-1402:1310 (2015)

PMID: 26835000