Development of tools to study molecular mechanisms of neural circuit formation

Classical genetic studies in mouse do not allow for the precise temporal control of loss of gene function during embryonic development. Therefore, we have developed in ovo RNAi, a method that allows us to silence genes in a precisely timed manner during development of the embryonic chicken spinal cord. We are refining this tool and transferring it to other areas of the central but also the peripheral nervous system. For example, ex ovo RNAi can be used to study the molecular mechanisms of axon guidance in the developing cerebellum.

 

In ovo RNAi
In ovo RNAi

Tissue clearing and light-sheet microscopy (mesoSPIM) allow for visualization of neural circuits in the intact embryo. In contrast to tissue sections or organotypic slices, whole-mount preparations of the brain or the peripheral nervous system provide a rapid overview on neural circuits without the interference of cutting angle or experimentally induced distortion.
Ideally, axons can be followed during navigation using in vivo live imaging. The comparison of axonal behavior at choice points between experimental and control-treated embryos provides clues on the mechanisms of axon navigation.