NOTE: Please feel free to use any of the movies below — all I ask is that you properly credit them. Science should always be shared, but it’s important to be able to trace the source. Thanks!
ASCB Cell Dance 2012 Winner
Overview of Drosophila Dorsal Closure
At a late stage of Drosophila embryogenesis, the embryo covers itself in epidermis. The lateral epidermis zippers closed while the central amnioserosa cells constrict and apoptose.
Ubiquitin promoter driven UAS Moesin actin binding domain fused to eGFP.
During dorsal closure lateral epidermal cells produce filopodia and lamellipodia along their leading edge
As the embryo covers itself in skin, the leading edge of the lateral epidermis (adjacent to the amnioserosa which is not seen in this movie) produces both broad lamellipodia and long-thin filopodia.engrailed promoter driven UAS actin eGFP fusion.
Overexpression of Enabled produces ectopic filopodia
Increasing levels of Enabled, a barbed-end actin binding polymerizer, results in increased filopodia along the leading edge and at tricellular junctions more ventral to the leading edge.
Engrailed driven UAS actin eGFP fusion (cyan) and UAS RFP Ena (not shown)
Enabled localizes to the tips of filopodial protrusions
Overexertion of Enabled reveals increased filopodia and that Enabled localizes to filopodia tips.
Engrailed driven UAS actin eGFP fusion (cyan) and UAS RFP Ena (red)
Overexpression of Diaphanous produces different ectopic filopodia
Increasing levels of active Diaphanous (another actin polymerizer) in the lateral epidermis during dorsal closure results in many ectopic filopodia all over the cell cortex. Note that there are more dynamic filopodia along the leading edge and at tricellular junctions more ventral to the leading edge.
Engrailed driven UAS Dia CA (not shown) and UAS RFP Ena
During dorsal closure the central amnioserosa cells produce filopodia too
During dorsal closure, while the embryo is covering itself in skin, the central amnioserosa cells which constrict an apoptose also produce filopodial protrusions. Note central cell has been photo bleached prior to the movie starting to provide contrast with which to see filopodia.
Ubiquitin promoter driven UAS Moesin actin binding domain fused to eGFP
All movies above were taken on either a Perkin Elmer Spinning Disc or a Visitech VT Hawk (each with Nikon scope body)
All movies above associated with the following publication:
Nowotarski, S.H., McKeon, N., Moser,R.J., and Peifer M (2014) The actin regulators Enabled and Diaphanous direct distinct protrusive behaviors in different tissues during Drosophila development. Molecular Biology of the Cell. 25(20).PMID:25143400