Coordinating plant pigment production: A green role for ORANGE family proteins.

Chlorophylls and carotenoids are essential pigments for photo-synthesis and plastid/plant development.Chlorophylls are uti-lized for light harvesting and primary charge separation,whereas carotenoids are accessory light-harvesting pigments that also play major roles in photoprotection,in the assembly and stability of photosystems,and as precursors to phytohormones and other important signaling molecules.The biosynthesis of these pig-ments must be precisely regulated to ensure their balanced pro-duction for the synthesis,assembly,and maintenance of the photosynthetic apparatus.