Role of plastids and mitochondria in the early development of seedlings in dark growth conditions.

Establishment of the seedlings is a crucial stage of the plant life cycle. The success of this process is essential for the growth of the mature plant. In Nature, when seeds germinate under the soil, seedlings follow a dark-specific program called skotomorphogenesis, which is characterized by small, non-green cotyledons, long hypocotyl, and an apical hook-protecting meristematic cells.

Limiting etioplast gene expression induces apical hook twisting during skotomorphogenesis of Arabidopsis seedlings.

When covered by a layer of soil, seedling development follows a dark-specific program (skotomorphogenesis). In the dark, seedlings consist of small, non-green cotyledons, a long hypocotyl, and an apical hook to protect meristematic cells. We recently highlighted the role played by mitochondria in the high energy-consuming reprogramming of Arabidopsis skotomorphogenesis.