Characterization of neurogenic niches and radial glial cells in the telencephalon of sharks: Comparative aspects and evolutionary implications

Abstract

The telencephalon experiments many morphological and cytoarchitecture changes along evolution. For gaining understanding of the evolution of the telencephalon, we have analyzed the spatio-temporal pattern of several neurogenic and radial glial markers during telencephalic development and adulthood in the cathsark, Scyliorhinus canicula. We have found a highly conserved expression pattern of neurogenic markers and morphologically and molecularly heterogeneous radial glial cells. In addition, we have investigated whether these markers and radial glial cells are present along the entire life of sharks and constitute the basis of adult neurogenesis in basal vertebrates. We have explored the evolutionary implications of the main similarities and differences we found with respect to other vertebrates.