February 5, 2014

The next time you try swatting away that little fruit fly from a neighboring lab while you enjoy your midday coffee break, take a beat and appreciate how stinkin’ purrrty those flies are. Today’s image features the developing egg of the fruit fly, and accompanies a paper describing the important role for prostaglandins in the (very photogenic) process.

Prostaglandins (PGs) are small lipids that act as signaling molecules in various physiological processes such as pain, inflammation, and platelet aggregation. On the cellular level, PGs regulate the organization of the actin cytoskeleton. A recent paper in Molecular Biology of the Cell from the Tootle lab sheds light on the role of PGs in development, and shows that PGs temporally regulate actin cytoskeleton organization during Drosophila oogenesis. Specifically, PGs function at stages 9 and 10 of oogenesis to inhibit, then promote, actin remodeling via the actin elongation factor Ena. Loss of PG signaling at stage 9 triggers early actin filament formation and bundling, while loss of PG signaling at stage 10 triggers a reduction of, or complete loss of, parallel actin filament bundling. As seen in the images above, actin filament organization (white) is abnormal in two different PG mutant follicles (middle, bottom), compared to a wild-type follicle (top).

Andrew J. Spracklen, Daniel J. Kelpsch, Xiang Chen, Cassandra N. Spracklen, & Tina L. Tootle (2014). Prostaglandins temporally regulate cytoplasmic actin bundle formation during Drosophila oogenesis Molecular Biology of the Cell, 25 (3) DOI: 10.1091/mbc.E13-07-0366