Forebrain Evolution
The forebrain lies at the top of the nervous system hierarchy and directs all complex behavior in vertebrates. As such, it became the evolutionary playground of the nervous system. It is at the forebrain where most divergences and novelties are clear. In the lab we try to bring light onto the developmental mechanisms that enable forebrain diversification in amniotes. Specifically, we research stem cell types, neurogenesis and neuronal migration.
Evolution of the Vertebrate Brain Plan
From a frog to a chimp, the brain of every vertebrate species organizes following a common pattern. This shared plan, that we term the phylotypic brain, appears obvious during early stages of development. The phylotypic brain has been conserved for over 500 million years and may have been preserved due to the constraint of the body plan evolution. How was this extreme conservation possible? What genetic mechanisms preserved the shared brain plan in vertebrates? Our group investigates the neural stem cell types that comprise the phylotypic brain and the conservation of their genetic features.
Cortical Development
The neocortex is the brain structure that most differentiates mammalian species. Its size and complexity are the human signature in nature. How the neocortex appeared in evolution? What changes in the developmental program of the brain triggered the formation of the six-layered neocortex? Our group aims to identify the minor changes in pallial development that opened the door for the formation of the neocortex. We research the massive neurogenic increase, novel cellular migrations and shifted neuronal positioning.
Experimental models
The power of our approach lies in the robust comparison of three amniote species. We perform our experiments in the embryos of mouse (Mus musculus), chick (Gallus gallus), and gecko (Paroedura pictus). This range of species represents well the amniote diversity of brains.
In vivo electroporation
We transfect neural stem cells by electroporation of plasmid vectors. This way we introduce the expression of a reporter -usually GFP -or any other type of gene- in progenitor cells and their lineage. This method helps us understand brain development by in utero surgeries for mouse embryos, and in ovo interventions for chick and gecko.
Single cell RNA sequencing
A major drive of evolution is the evolution of cell types. We investigate the cell types that build the vertebrate brain by single cell RNA sequencing. This powerful method helps us reveal the transcriptome expressed by thousands of individual neural stem cells. By direct comparison of these transcriptomes on our experimental models, our goal is to shed light about the cell composition of the conserved embryonic brain. The understanding of these conserved cells will increase our knowledge on the evolution of the brain.