Photoregulation of Gene Expression during Chloroplast Biogenesis

Chloroplast biogenesis in higher plants is light dependent. The mature organelles differentiate either from rudimentary proplastids present in light-grown plants or from etioplasts which develop in plants maintained in darkness. Both types of transition are characterized by major changes in the structural organization, molecular composition and photosynthetic activity of the plastids, as discussed in a. recent review (Bradbeer 1981).