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Plants are by definition dependent upon photosynthesis, and virtually every aspect of plant life is affected by light. The phytochrome (phy) family of proteins, along with other photoreceptor systems, enables plants to monitor ambient light conditions. The phy family has been observed for decades to function in the plant cell cytoplasm, but the means by which phy proteins relay their evaluation of light conditions to the nucleus and regulate gene activity has not been defined. To assess the intracellular localization of phy proteins, Kircher et al. (pages 1445-1456) have fused members of the family to the green fluorescent protein (GFP). A functional phyA-GFP fusion product expressed in a trichome cell of an adult tobacco plant is visible on the cover as green material that is concentrated within the nucleus. The orange-red spherical objects arise upon epifluorescence of chloroplasts in the cytoplasm. The translocation of phyA and phyB into the nucleus is differentially light-regulated and may result in specific nuclear interactions that underlie phy-mediated changes in gene expression.