Control of epithelial morphogenesis in vertebrates

JUAN RAMÓN MARTÍNEZ MORALES

The main focus of our laboratory is to study cellular and molecular mechanisms involved in the morphogenesis of the vertebrate eye. Using zebrafish (Danio rerio) and medaka (Oryzias latipes) as genetic models, we aim to understand this process at very different and complementary levels. We explore how gene regulatory networks control tissue identity; how this translates in precise shape changes, as well as polarized contractility and cellular adhesion; and how cellular tensions are transmitted within the tissue to determine the final shape of the organ.

Optic cup folding in zebrafish, as revealed in a tg(vsx2.2:GFP-caax) embryo. Imagingstarts at 17 hpf.

The use of two far related teleost models (i.e. their lineages separated 200 mya) allows investigating the universality and relative contribution of the cellular and genetic mechanisms that control organ shape. In addition, due to the strategic position of teleost fish within the vertebrate evolutionary tree, our research often uncovers interesting evo-devo questions that are relevant to understand the evolutionary history of the vertebrate lineage. Therefore, questions such as, how new developmental mechanisms appear and how do they contribute to the emergence of vertebrate anatomical innovations, are among the research interests of the laboratory.

Myosin foci dynamics and basal membrane indentations in 20 hpf control and blebbistatin treated embryos from he line tg(actb1:myl12.1-eGFP)

During the last years, we have become increasingly aware that an important part of our developmental studies –particularly those exploring the divergence between the neural retina and retinal pigmented epithelium (RPE) genetic programs– are also relevant in the context of retinal diseases. This seems particularly the case for retinal degenerative pathologies, for which understanding the genetic program specifying the RPE is key to improve the efficiency of recently developed cell-based therapies.