CHS Background Information
Arabidopsis development is mediated by several environmental stimuli. Light plays an important role in many developmental processes, including photosynthesis, chloroplast biogenesis, leaf initiation, and floral induction (1). Light-dependent development, called photomorphogenesis, relies heavily on the action of five phytochromes, PhyA, B, C, D, and E, which are involved in photoperiod sensing and the shade avoidance syndrome (2-4). These phytochromes are partially regulated by transcriptional repressors of photomorphogenic development, such as COP1 and COP9 (5,6). Other light sensitive proteins include CAB (chlorophyll a/b-binding), which is essential for chloroplast development, and chalcone synthase (CHS), which mediates the flavinoid biosynthetic pathway (7,8).
