Cendra Agulhon



Conference room R229
Campus Saint Germain des Prés de l'Université de Paris, 45 rue des Saints Pères, Paris 6e


13 May 2022


11 h 30 min - 12 h 30 min


Neuroscience Seminar Series

Development and evolution of visual projections, by Alain Chédotal

Summary Development and evolution of visual projections

In most animal species including humans, commissural axons connect neurons on the left and right side of the nervous system. This communication between the two sides of the brain and spinal cord is necessary for a series of complex function, including binocular vision, coordinated locomotor movements, and sound direction localization. In humans, abnormal axon midline crossing during development causes a whole range of neurological disorders ranging from congenital mirror movements, horizontal gaze palsy, scoliosis or binocular vision deficits. The mechanisms which guide axons across the CNS midline were thought to be evolutionary conserved but our recent results suggesting that they differ across vertebrates.  I will discuss the evolution of visual projection laterality.  In most vertebrates, camera-style eyes contain retinal ganglion cell (RGC) neurons projecting to visual centers on both sides of the brain. However, in fish, RGCs are thought to only innervate the contralateral side. This suggested that bilateral visual projections appeared in tetrapods as an adaptation to aerial vision. Using 3D imaging and tissue clearing we found that bilateral visual projections exist in non-teleost fishes. We also found that the developmental program specifying visual system laterality differs between fishes and mammals.

Short Biography

Dr Alain CHEDOTAL received a PhD degree from Pierre & Marie Curie University in Paris and completed his postdoctoral research at UC Berkeley. He was recruited at INSERM in 1997 and is currently Research director (DRCE) at the French National Institute for Health and Medical Research (INSERM) and group leader at the Vision Institute in Paris. His research aims at understanding how cell-cell interactions are regulated by axon guidance molecules during normal development and in pathologies. Most of his studies are conducted in vivo using a variety of mouse models video-microscopy and biochemical methods. In the past few years he has developed novel molecular and imaging techniques (such as tissue clearing an 3D light sheet microscopy) to study axon guidance and embryology. His team contributes to the human cell atlas project and started to build the first 3D cellular atlas of the developing human embryo. more information