Update: Shining light on the function of NPH3/RPT2-like proteins in phototropin signalling

Blue light regulates diverse functions including phototropism and chloroplast movements. Christie et al. summarize recent updates in understanding the signalling pathway between light perception by phototropins and downstream responses. They describe the central roles for the 33 members (in Arabidopsis) of the NRL protein family, named for the founding members NON-PHOTOTROPIC HYPOCOTYL (NPH3) and ROOT PHOTOTROPISM 2 (RPT2), and the four members of the  PHYTOCHROME KINASE SUBSRTATE (PKS) protein family. The authors also summarize the evolutionary origins of the blue-light signalling pathway in the green plant lineage and highlight ongoing questions including the need for biochemical characterization of many of these proteins. Plant Physiol. 10.1104/pp.17.00835