The role of the COP1, SPA, and PIF proteins in plant photomorphogenesis

Molecular systems governing light-signal transduction at early stages of plant development are reviewed. Possible pathways for light-signal transduction via photoreceptors (phytochromes), as well as the functions of positive and negative regulators, are considered. Current notions of mechanisms responsible for photomorphogenesis repression in the dark and in the light are discussed.