The egg of the fruit fly, Drosophila melanogaster, is constructed through the coordinated efforts of many cells.  The nurse cells, whose large nuclei can be seen in purple, maintain connections with each other and the oocyte through ring canals (blue circles).  These bridges allow nurse cells to dump their products into the oocyte at maturation.  The follicle cells are smaller and surround the outside of the egg chamber.  Their nuclei are visible as small round purple structures.  The follicle cells mediate yolk deposition in the egg and create the eggshells.  Polar cells (green) are a specialized pair of follicle cells at the anterior (left) and posterior (right) of each egg chamber.  These polar cells organize and determine fates of the other follicle cells.  Anterior polar cells also form extensions that create a channel in the egg micropyle through which sperm can enter to fertilize the egg.

Image type: Fluorescence imaging by laser scanning confocal microscopy

Instrument: Leica TCS SP8 DLS

Labels: Phalloidin (blue), DAPI (purple), GFP (green)

Processing: Leica LAS-X, Huygens Essentials Deconvolution, Adobe Photoshop

Microscopist: Michelle Giedt, Ph.D.