Balancing different types of actin polymerization at distinct sites: roles for Abelson kinase and Enabled.

The proto-oncogenic kinase Abelson (Abl) regulates actin in response to cell signaling. Drosophila Abl is required in the nervous system, and also in epithelial cells, where it regulates adherens junction stability and actin organization. Abl acts at least in part via the actin regulator Enabled (Ena), but the mechanism by which Abl regulates Ena is unknown.

Cytoskeletal connections: building strong cells in new ways.

Cell and tissue integrity requires the coordination of actin and microtubules and the linkage of these cytoskeletal elements to cell junctions. New findings reveal that the cytoskeletal linker protein Short stop works with EB1 and APC1 to help carry out this function.

Drosophila APC2 and APC1 play overlapping roles in wingless signaling in the embryo and imaginal discs.

The regulation of signal transduction plays a key role in cell fate choices, and its disregulation contributes to oncogenesis. This duality is exemplified by the tumor suppressor APC. Originally identified for its role in colon tumors, APC family members were subsequently shown to negatively regulate Wnt signaling in both development and disease.