Ewch i’r prif gynnwys
Sonia Lopez De Quinto

Dr Sonia Lopez De Quinto

Senior Lecturer

Ysgol y Biowyddorau

+44 29208 79008
Adeilad Syr Martin Evans, Ystafell W/3.20, Rhodfa'r Amgueddfa, Caerdydd, CF10 3AX
Ar gael fel goruchwyliwr ôl-raddedig


My group studies the molecular mechanisms regulating mRNA translation in time and space.  Our focus is on understanding the role of conserved RNA-binding proteins in these processes, as well as the molecular code governing RNA-protein complex formation and how these complexes define where specific mRNA transcripts engage with cytoplasmic ribosomes for protein synthesis.

This type of post-transcriptional gene expression regulation in the cell cytoplasm allows cells to respond quickly to external stimuli and plays a pivotal role in the establishment and maintenance of cell polarity. mRNA targeting coupled to translational control underlies essential biological processes such as body axis formation during development, morphogen secretion, synaptic plasticity, cell migration and thus, tumour invasiveness.

Using Drosophila as a model system and a variety of techniques, we seek to identify and functionally characterize in vivo localized mRNAs sharing similar regulatory networks.


  • Senior Personal Tutor
  • Admissions Tutor (Biochemistry)
  • Assessment Leader BI3254 Genes to Genomes

Interested in joining my lab as a self-funded post-graduate student or a postdoc/fellow?  Please contact me by email.












Regulation of mRNA translation in time and space

Many biological and cellular functions rely on the generation and maintenance of cell asymmetries, also known as cell polarity.  Sub-cellular mRNA localization coupled to translation in a confined cytoplasmic region has emerged as a powerful mechanism to restrict protein synthesis in time and space, leading to the polarisation of the cell.  Consistent with this, local translation of asymmetrically enriched mRNAs underlies essential biological functions such as embryonic development or synaptic plasticity.  Furthermore, recent work has unravelled the role of RNA-based gene regulation in the development of human diseases such as cancer, genetic neurological disorders and viral infections. Thus, understanding the mechanisms governing formation and regulation of RNA-protein complexes (RNPs) is a pre-requisite for the design of new intervention strategies.

Previous work

Using the fruit fly Drosophila as a genetically tractable model organism, and specifically the highly polarised oocyte, we have characterized different aspects of RNA regulation that control development of the future embryo's body axes.  These regulatory mechanisms include the formation of transport-competent RNP particles, their interaction with the cytoskeleton, and the coordination between the transport and translation machineries.

Our work has contributed to our understanding of how the actin and microtubule cytoskeletons cooperate in the asymmetrical enrichment of mRNAs in the Drosophila oocyte (Krauss & Lopez de Quinto et al., 2009).

We have also identified and characterized two conserved RNA-binding proteins as key oskar regulators. Hrp48 binds to the 5´ and 3´ ends of oskar mRNA to regulate its transport to the posterior pole, while keeping the mRNA silent (Yano et al., 2004).  In contrast, PTB binds preferentially to the oskar 3´UTR and, although dispensable for transport, it is essential for oskar mRNA translational repression.  Our data points to PTB is a key structural component of oskar RNP complexes that functionally links formation of high-order RNP particles and translational silencing (Besse & Lopez de Quinto et al., 2009).

Our research interests

Hrp48 and PTB belong to the heterogeneous nuclear ribonucleoprotein family (hnRNP) of proteins.  These general RNA-binding proteins associate with transcripts as they are synthesized and control multiple aspects of RNA processing, both in the nucleus and cytoplasm.  Not surprisingly, changes in the activity of these general RNA-binding proteins are associated with a broad range of developmental and cellular defects, as well as human pathologies such as cancer.  However, it is still not clear how hnRNP proteins discriminate among multiple RNA targets and most importantly, the mechanisms that these RNA-binding proteins employ to specifically regulate each RNA target.

Our work aims at elucidating the principles governing the assembly and dynamics of those RNP complexes that regulate the targeting and/or translation of asymmetrically enriched mRNAs.  To this end, we are using functional assays to characterize in vivo the binding of several regulatory proteins to their specific RNA targets, in a genetically tractable model organism such as the fruit fly Drosophila melanogaster. This knowledge will allow us to predict and test how newly identified RNAs may be regulated by similar proteins.  By identifying new targets of regulatory RNA-binding proteins we aim at discovering new cellular processes regulated by the local expression of RNAs.  This will ultimately lead to the identification of potential targets for the design of therapeutic entities, enabling us to gain control of the expression of genes in the cell cytoplasm.

The goals of our research are:

  • Functional characterization of regulatory RNA-protein interactions.
  • Identification of conserved RNA cis-acting motifs in asymmetrically localized mRNAs regulating their localization and translation.
  • Identification of new regulatory trans-acting factors involved in the local translation of RNAs.
  • Characterization of the cellular mechanisms underlying mRNA localization and translation regulation.
  • Identification and characterization of new RNA targets associated with similar RNP complexes, using biochemical and computational approaches.
  • Elucidation of the role that local expression of asymmetrically enriched RNAs plays in different cellular and developmental processes.

Current lab members

  • Sean Hubbert (Integrated Masters Year 4 Project, 2018-2019)
  • James Evans (PTY student, 2018-2019)

Research mentors and collaborators

  • Encarnación Martínez-Salas (CBMSO, Spanish National Research Council, Spain)
  • Anne Ephrussi (EMBL Heidelberg, Germany)
  • Carolina Pérez-Iratxeta - Ottawa Health Research Institute, Ottawa (Canada)
  • Will Wood (The University of Edinburgh)


  • BI2232 - Biochemistry
  • BI2234 - Molecular Biology of the Gene
  • Year 2 - Week Long Practical - From Foods to Pharmaceuticals: The Promise of Recombinant Alginate Lyases
  • BI3254 - Genes to Genomes


Career profile

I graduated in 1995 with a BA in Science (Chemistry) from Universidad Autónoma de Madrid (Spain), where I also carried out my PhD. In 2002 I joined the EMBL Heidelberg (Germany) for my post-doctoral studies and moved to the School of Biosciences at Cardiff University in December 2007, with support by a RCUK Fellowship in Translational Research in Experimental Medicine.

My long-standing research interests focus on gene expression regulation, with a special emphasis on those mechanisms operating at the mRNA level. Recent findings have highlighted the crucial role that RNA regulation has in tuning the expression of batteries of genes that the cell requires for specific tasks. However, our knowledge of the molecular mechanisms operating at different levels to regulate the expression and fate of mRNAs remains limited.

During my Masters and PhD research (Madrid, Spain), I analysed the mechanism employed by a highly specialized viral RNA region called IRES (Internal Ribosome Entry Site) to recruit the translational machinery to an internal start codon. My work led to the identification of conserved RNA motifs involved in the three-dimensional folding of the IRES and in the establishment of RNA-protein interactions that are essential for translation initiation. This work significantly contributed to the understanding of how gene expression regulation is achieved in RNA viruses.

During my postdoctoral studies at the EMBL (Heidelberg, Germany), I developed a deep interest in the impact that RNA regulation has on the cellular processes ultimately regulating development and disease progression. Specifically, I studied the mechanisms underlying the asymmetric distribution in the oocyte of cell fate determinants, which define the body axes of the future embryo. Over the last years, I characterized in vivo the role of key regulators of oskar mRNA post-transcriptional regulation, such as the cytoskeletal components cooperating in the asymmetrical enrichment of an mRNA in a polarized cell, and the RNA-binding proteins and cis-acting RNA motifs coordinating the transport of an mRNA to its translational control. These results have been crucial to understand the mechanisms operating on asymmetrically enriched mRNAs to control their sub-cellular targeting and local expression.

Professional memberships

Fellow of the Higher Education Academy

Member of the British Society for Developmental Biology

Member of the Biochemical Society

Member of the Spanish Society of Biochemistry and Molecular Biology

Aelodaethau proffesiynol

Fellow of the Higher Education Academy

Member of the British Society for Developmental Biology

Member of the Biochemical Society

Member of the Spanish Society of Biochemistry and Molecular Biology

Meysydd goruchwyliaeth

Research in my lab revolves around the themes listed below. If this is of interest to you, please contact me so we can generate a project outline together.

  • RNA Biology
  • RNA binding proteins (RBP)
  • RNA localisation
  • Translation regulation
  • Developmental Cell Biology
  • Post-transcriptional regulation of gene expression

Current PhD projects as Main Supervisor:

  • Abdulla Almoalem (2019-current), funded by United Arab Emirates government.
  • Nehad Silan (2022-current), funded by Saudi Arabian government.

Current PhD projects as Second Supervisor:

  • Dana Jackson (2020-current), BBSRC SWBio PhD DTP studentship.

Goruchwyliaeth gyfredol