The cover of the March 2011 issue of Cold Spring Harbor Protocols, out today, features several striking images of mouse and quail embryos.  The method used to produce the images, microscopic magnetic resonance imaging (μMRI), is a noninvasive imaging technique that permits the visualization of regions deep within embryos that are inaccessible using optical methods.  During μMRI, the specimens remain in near-physiological conditions, remaining anatomically unperturbed.  The method is ideal, therefore, for generating developmental atlases of these organisms.

Quail embryos in a "relaxed" posture used to construct a μMRI-based developmental atlas. (©2011, CSHL Press)

In an accompanying article, the authors, Seth Ruffins and Russell Jacobs (Caltech Biological Imaging Center), describe the preparation of specimens for μMRI and appropriate applications of μMRI for developmental biology, including the construction of atlases.  Using these methods, they have successfully generated digital anatomical atlases of both quail and mouse development (see the Caltech MRI Atlases).  These atlases, and others constructed using μMRI, will be useful references for developmental biologists, providing identifiable anatomical landmarks and standards for comparison.