Shining LIGHT on functional promiscuity in the TNF and TNFR superfamilies.

In this issue of Structure, Liu and colleagues report the structure of the TNF superfamily member LIGHT bound to decoy receptor 3 (DcR3). Both LIGHT and DcR3 interact with multiple binding partners. The authors identify a conserved interaction important for affinity as well as additional interactions that can be targeted to introduce selectivity.