New imaging technologies have revolutionized the study of developmental biology. Where researchers once struggled to connect events at static timepoints, imaging tools now offer the ability to visualize the dynamic form and function of molecules, cells, tissues, and whole embryos throughout the entire developmental process. In order to observe development over time, it is necessary to grow the embryos of laboratory model organisms on the microscope stage, and keep them as healthy and in as natural a state as possible. Methods for culturing and imaging the embryos of model organisms are featured in the December issue of Cold Spring Harbor Protocols.

Caenorhabditis elegans has been a key organism for understanding cellular differentiation and development. The fate of every one of the worm’s somatic cells has been mapped out, and its short developmental time, transparent shell, and nonpigmented cells makes C. elegans an ideal subject for imaging studies. Timothy Walston from Truman State University and Jeff Hardin from the University of Wisconsin-Madison provide An Agar Mount for Observation of Caenorhabditis elegans Embryos, an easy way to prepare live C. elegans embryos for microscopic visualization. The method involves embedding the embryo in agar to hold it in place,providing a fixed orientation for consistent imaging. Embryos prepared this way are amenable to both light microscopy and confocal microscopy. As one of our featured articles, the protocol is freely available to subscribers and non-subscribers alike.