Preparing early whole-mount Drosophila embryos for immunostaining

INTRODUCTIONThe choice of fixation and permeabilization methods for examining flies depends on their stage of development. Early embryos (0-17 hours or until cuticle formation) are treated with a mixture of organic solvents, formaldehyde, and alcohols, as described here. The cuticles of late-stage embryos are usually opened by sonication. Tissues from more advanced stages of development are normally dissected by hand and then fixed and stained in a standard paraformaldehyde/detergent combination.