Plants use light not only for photosynthesis. Although the plant cell does not have eyes, it can still perceive light and thus its environment. Phytochromes, certain turquoise proteins, play the central role in this process. How exactly they function is still unclear. Now a team led by plant physiologist Jon Hughes (Justus Liebig University Gießen) has been able to decipher the three-dimensional architecture of various plant phytochrome molecules at BESSY II. Their results demonstrate how light alters the structure of the phytochrome so that the cell transmits a signal to control the development of the plant accordingly.
Plants use light to live, via a process called photosynthesis. Yet, they do use light also by so called phytochromes – special molecules that give plants a kind of sight and can thus control the biochemistry of the cell and the development of the plant. It is now known that phytochromes regulate almost a quarter of the plant genome.
However, it was unclear how phytochromes function exactly: How is the light absorbed? What happens in the molecule afterwards, how is the light signal transmitted?
Read more on the BESSY II (at HZB) website
Image : Inside the 3D-structure of a phytochrome a bilin pigment absorbs the photon and rotates, which triggers a signal.
Credit: © Jon Hughes