Cyril Dominguez

Short Biography

Dr Dominguez is a structural biologist interested mainly in protein-RNA interactions involved in the regulation of alternative splicing and joined the University of Leicester in 2015. His research group is also interested in the role of pre-mRNA secondary and tertiary structures on alternative splicing regulation, and studies RNA protein-protein and protein-RNA complexes using structural biology techniques (NMR and X-ray) biophysical methods (ITC Fluorescence polarization) and biochemical methods (RNA footprinting EMSA).

Cyril Dominguez obtained his BSc and MSc in Biochemistry from the University of Aix-Marseille (France) and a PhD at the University of Utrecht (The Netherlands). After his PhD in 2004 he joined the laboratory of Fred Allain at the ETH Zurich (Switzerland) where he studied the interaction between the splicing factor hnRNP F and G-tract RNAs. In 2010 he obtained an MRC Career Development Award Fellowship to initiate his own research programme at the University of Leicester. In 2015 he became a lecturer and in 2018 an Associate Professor at the University of Leicester.

AMBER postdoctoral fellowship subject (second call)

Project 1: Structural investigation of the intrinsically disordered regions of the RNA binding protein Sam68: implication for RNA binding and phosphorylation

Intrinsically disordered regions (IDRs) or protein play crucial roles in almost all cellular functions. Still, the molecular mechanisms that govern their functions remains largely unknown. In recent years, classical structural and biophysical techniques (NMR, FRET, SAXS, ...) have been combined with molecular dynamics simulations to generate structural ensembles and derive the mechanisms of their functions. Sam68 is a typical RNA binding protein that contains a classical folded RNA binding domain flanked by N-terminal and a C-terminal IDRs. While these IDRs have been shown to be crucial for the function of Sam68 and are targets of multiple post-translational modifications, the molecular mechanisms of their contribution remains unknown. Our published (Malki et al, NAR, 2022) and preliminary data clearly show that the Nter and Cter IDRs of Sam68 have the ability to bind RNA specifically and that phosphorylation of a single threonine residue inhibits their RNA binding ability and consequently the cellular functions on the protein.

This raises three important questions:

1- How does an unstructured protein region bind specifically an unstructured RNA? What are the molecular basis for the specificity?

2- How does phosphorylation of a single-amino acid have such an impact on the RNA binding properties of the protein?

3- How does full-length Sam68 recognize specifically its RNA targets

We will answer these questions by combining the team expertise in structural and biophysical methods (NMR, FCS, FRET, SAXS) with molecular dynamics to decipher the structural properties of these regions free, in complex with RNA and following phosphorylation.

Project leadership team: Cyril Dominguez (University of Leicester), Andrew Hudson (University of Leicester), Marie Skepo (Lund University)

Project 2: Biomolecular assemblies in healthy development and cancer

The nucleus is organized into membraneless, yet functionally distinct compartments. We now know that many nuclear compartments are organized by an array of non-coding RNAs implicated in diverse gene-regulatory processes including embryonic development, cell type-specific phenotypes and cancer. These RNAs acts as hubs/scaffolds for effector proteins forming complex biomolecular assemblies.

Intrinsically disordered regions (IDRs) have recently emerged as key players in the formation of biomolecular assemblies by driving weak, multivalent protein-protein interactions. We have previously identified that the IDRs of the transcriptional corepressor SPEN are essential for protein condensation within large ribonucleoprotein complexes. This supramolecular aggregation is essential for gene regulation. However, how IDR interactions form, their selectivity and contribution to multivalency or how interactions are perturbed in disease remains unclear.

This project will employ a multidisciplinary approach across scales to elucidate the function of these assemblies, their molecular organization, dynamic protein-protein and RNA-protein interactions. We will integrate state-of-the-art methods in stem cell biology and genome editing with super-resolution microscopy, biophysical and structural methods. We will use is silico structure predictions to determine the IDR-containing region(s) that are critical for self-interaction and condensation. We will express minimal RNA-protein assemblies and conduct structural studies by cryo-EM and NMR. We will next perturb these interactions, in vitro through peptide inhibitors which will guide in vivo genetic perturbations followed by downstream analyses within cells by super-resolution microscopy and quantitative image analyses. These pipelines will be significant towards the generation of imaging biomarkers with relevance in dysregulation of biomolecular condensates in cancer.

Project leadership team: Yolanda Markaki (University of Leicester), Cyril Dominguez (University of Leicester), John Schwabe (University of Leicester)

Location: Leicester, UK

Organisation: University of Leicester, Department of Molecular Cell Biology

Links

AMBER call in EURAXESS main call (starting point for application)

Guide for applicants

Cyril Dominguez's Profile on the University of Leicester website

Department of Molecular Cell Biology, University of Leicester

Info about employment at the University of Leicester