Speaker
Description
Following the divergence of the last common ancestor of vertebrates, vertebrate brains have undergone over 500 million years of divergence and diversification, forming unique cellular networks and substructures in response to varying environmental conditions and selective pressures. Although there is a vast and growing body of research concerning the structure and function of mammalian brains, considerably less is known about brain structures and their associated functions in non-tetrapod vertebrates. Despite their expansive evolutionary distances, vertebrate brains share major structural subdivisions, including a hindbrain, midbrain, and forebrain, with similar expression patterns of major marker genes and connectivity across regions, suggesting that these structures were present in the ancestral vertebrate brain. To develop a more fine-scale understanding of the extent of conservation and divergence among vertebrate brains, we are using single nucleus sequencing and high-resolution spatial transcriptomics to build cellular-level atlases of adult vertebrate brains, focusing on understudied cyclostomes and aquatic vertebrate lineages. Using whole transcriptome correlations and comparative phylogenetic methods, we are identifying highly conserved cell types and inferring the evolutionary histories of novel cell types that arose in more recently diverged lineages, such as myelinating oligodendrocytes. Together, these datasets will allow us to identify coevolving transcriptional networks that define cell types and will bring us closer to the goal of defining sets of principles dictating brain cellular and structural evolution.
