(molecular evolution with a focus on development)

The impact of new mutations

A key feature of Darwinian evolution is that differences between species begin first as variation within species. We've learned a great deal about how natural selection acts on genetic variation, but we know much less about how this variation arises in the first place. Using mutation accumulation lines and targeted mutagenesis in Drosophila, we aim to characterise the impact of new mutations on gene expression during development and, in particular, how new mutations contribute to the appearance of so-called  phylotypic stages.

The evolution of developmental gene regulatory networks

Developmental gene expression profiles are the result of complex regulatory interactions that can act to buffer gene expression from mutations and environmental perturbations. At the same time, changes in developmental gene expression are essential for the evolution of novel phenotypes. To better understand how regulatory interactions facilitate, buffer, and constrain developmental evolution, we make use of decades of work aimed at uncovering the gene regulatory network underlying mesodermal specification and skeletal grown in the larval sea urchin. Specifically, we focus on how this network has evolved between species of Strongylocentrotus sea urchin using a combination of genomic methods (e.g. RNA-/ChIP-Seq), single-cell sequencing technologies, and computational scans for positive selection. 

Identifying DNA-regulatory elements in non-traditional model systems

A crucial component of understanding how gene expression evolves is knowing where in the genome to look. But while DNA sequencing has become cheaper and easier with every passing year, interpreting the results has not. This is particularly true for non-coding, regulatory DNA for which, unlike protein coding regions, the relationship between DNA sequence and function is poorly understood. Central to our lab's efforts in understanding how developmental gene expression evolves is the annotation of regulatory DNA in echinoderms and non-melanogaster fruit flies using a combination of experimental and computational techniques.