Why plant cells need heme: Hidden signal reshapes photosynthesis gene control

For plants, light is an important environmental factor not only as a source of energy for photosynthesis, but also as a signal for capturing environmental information.

Light signals are sensed by photoreceptor proteins called phytochromes.

The amino acids that make up proteins are transparent and cannot absorb visible light.

Therefore, pigments are essential for photoreceptor proteins to sense light, and these are called chromophores. ...