Myelinated axons comprise about half the volume of our central nervous system and are essential to its formation, function, and life-long health. Work over the past decade has established the zebrafish as a valuable model for the study of myelinated axons. The embryos and larvae of zebrafish have fantastic properties for live cell imaging in vivo. Their small size, rapid development and optical transparency, coupled with the availability of numerous fluorescent reporters, allow visualisation of cellular and molecular behaviours in vivo in ways that are not possible in other systems. I will give an overview of the tools that we have developed in my laboratory to study myelinated axons in vivo, and focus on our recent work investigating how axon-oligodendrocyte interactions regulate the dynamics of myelination in the CNS. Zebrafish are also amenable to large-scale genetic and chemical screens, and I will provide an update on novel insights gained into myelin formation, and maintenance through such screens.

In addition, I will also describe our recent establishment of a fully automated high-resolution chemical screening platform for the identification of compounds that may be employed to promote myelin regeneration and the treatment of disease. Finally, I will outline our burgeoning efforts to assess how the dynamic regulation of myelination by neural activity affects fundamental principles of circuit function.