Nonmammalian model systems of zebrafish

Glial cells in developing organisms are highly dynamic, often engaging in long-distance migration and specific cell interactions such as axon ensheathment. Such behaviors are difficult to observe directly using rodent and bird models; consequently, our knowledge of mechanisms that guide glial development remains incomplete. Zebrafish have emerged as a strong model system for glial cell investigations; their small size, optical clarity, and rapid development permit direct observation through time-lapse imaging. Furthermore, forward genetic screens for mutations that disrupt glial development can be carried out at relatively low cost, thereby helping to define genes with essential glial functions.