Slugging it out

Slugging It out: Fine Tuning the p53-PUMA Death Connection

In response to DNA damage, the tumor suppressor p53 elicits a complex cellular response. In this issue of Cell, Wu et al. (2005) show that the transcription factor SLUG is induced by p53 and protects hematopoietic progenitor cells from apoptosis triggered by DNA damage. SLUG exerts this protective role by repressing Puma, a proapoptotic target of p53. PUMA is also a key coordinator of apoptosis...

Sorting it out

The AP-2 adaptor complex is widely viewed as a linchpin molecule in clathrin-mediated endocytosis, simultaneously binding both clathrin and receptors. This dual interaction couples cargo capture with clathrin coat assembly, but it has now been discovered that the association with cargo is tightly regulated. Remarkably, AP-2 is not obligatory for all clathrin-mediated uptake, and several alterna...

Just Out of It

Check it out!

Desmosomes sort it out

iochemical and kinetic studies have failed to provide a unified view on how the Arp2/3 complex nucleates actin filaments. Does the complex, which mediates actin filament nucleation and branch formation at the leading edge of motile cells, bind to the side of an older actin filament, or does it become incorporated into that filament? B Structural studies now add a new dimension to the discourse,...