Research ArticleStructural Biology

Structure of a Light-Activated LOV Protein Dimer That Regulates Transcription

Science Signaling  02 Aug 2011:
Vol. 4, Issue 184, pp. ra50
DOI: 10.1126/scisignal.2001945

You are currently viewing the editor's summary.

View Full Text
As a service to the community, AAAS/Science has made this article free with registration.

Coming Together in the Light

The filamentous fungus Neurospora crassa uses two blue-light sensors, white collar-1 (WC-1) and VIVID (VVD), both of which contain light, oxygen, or voltage (LOV) domains, to regulate its responses to light. WC-1 and WC-2 form a complex (WCC) to drive expression of light-induced genes, including vvd, whereas VVD tunes responses to light by directly interacting with and antagonizing the function of WCC. Vaidya et al. solved the crystal structure of the light-induced dimer of VVD and compared it to previously determined structures of the dark-state, monomeric protein. This analysis revealed that light not only induced a conformational change in the positioning of the N-terminal cap of one subunit of VVD but also triggered the opening of a binding pocket in the opposing subunit, into which the N-terminal cap could dock. Determining the structure explained the functional responses observed in vvd-deficient Neurospora that expressed variant VVD proteins and may inform mechanisms by which LOV-containing proteins interact.