PI(4,5)P2 Colocalizes with the F-actin Focus at the Invasive Podosome

Lateral view of VA1 muscle (turquoise in first frame) with attached FCM (magenta in first frame) in a live DMef2-Gal4>UAS-PH^plcγ::GFP, UAS-mCherry::moe embryo. Time lapse taken at stage 14 (11.5 h AEL), with the FCM firmly attached to the myotube. Over the acquisition time, the PI(4,5)P2 enrichment overlaps temporally and spatially with F-actin at the cell-cell interface and disappears with the actual fusion event. Arrows point to accumulations of PI(4,5)P2; arrowheads to filopodia. Red arrow indicates fusion event with the disappearance of the FCM. Frame rate 45 sec, scale bar: 5µM.