01.03.2017 - 21:01
A  A


Genetic evolution of cerebral cortex size determinants
March 09, 2017 13:00
Speaker: Víctor Borrell (Institute of Neuroscience, CSIC-UMH, San Juan de Alicante, Spain)
Talk at the Department of Evolutionary Genetics

more information

Seminar Area Genetics

One of the most prominent features of the human brain is the fabulous size of the cerebral cortex and its intricate folding, both of which emerge during development. Brain size in reptiles, birds and mammals differs dramatically owing to developmental differences in speed of production and final abundance of neurons, but the genetic mechanisms behind this evolution of neurogenesis are largely unknown. Here I will discuss recent findings from my laboratory revealing novel cellular and genetic mechanisms that regulate cortical expansion and folding. In particular, we have analyzed neurogenesis in the mouse olfactory bulb and neocortex, two structures with different size and growth rate. In the olfactory bulb, direct neurogenesis from Radial Glia Cells is abundant, driving fast but limited neuron production, whereas in the larger neocortex most neurogenesis is indirect via basal progenitors. Gain- and loss-of-function manipulations in mouse, chick and snake embryos demonstrate that high Slit/Robo signaling, combined with Robo-dependent low Dll1 expression, are necessary and sufficient to drive direct neurogenesis. This mechanism is prevalent in the cerebral cortex of chick and snake embryos but dampened in mouse, allowing indirect neurogenesis. Our findings suggest that attenuation of Robo signaling contributed to increase neuron production and cortical expansion during mammalian evolution.

Anett Pechstein, +49 341 3550-504

E-mail: pechstein[>>> Please replace the brackets with an AT sign! <<<]eva.mpg.de
Website: http://www.eva.mpg.de