www.sciencemag.org SCIENCE VOL 337 6 JULY 2012 5 COVER Structure of the Wnt signaling molecule (red) in complex with the Frizzled ligand-binding domain (yellow), schematically depicted as connected to the cell surface. A key feature of this structure is the visualization of a lipid group (blue) on Wnt directly engaging Frizzled. The Wnt/Frizzled mode of binding paves the way for the design of W...

This Theme Section consists of 11 essays aiming to explore diverse issues related to academic freedom and tenure, presenting the views and thoughts of 15 scholars from different disciplines. Historical, legal, theoretical, philosophical, political and educational aspects of academic freedom and tenure are addressed; the decline in productivity of tenured faculty is questioned; and the effect of...