he seedling on the right was fed with a synthetic photoreceptor and opens it cotyledons. In the dark control (left seedling), they remain closed. Credit: T. Lamparter, KIT |
Plants
are dependent on the sun. Sunlight does not only supply them with
energy, but also controls their development steps. So-called
photoreceptors activate the processes of germination, leaf development,
bud formation, and blossoming in the cells. The light-absorbing
component of a photoreceptor may be replaced by a chemically similar
synthetic substance. For the first time, the effects on complete plants
are now described in the The Plant Cell journal.
“The
plants developed in the dark as if they were in light,” says the
Director of the studies Tilman Lamparter, Karlsruhe Institute of
Technology (KIT). The seeds and seedlings of thale cress were fed with a
synthetic substance named “15Ea-phycocyanobilin”. In the plant cell,
this substance replaces the natural, photoactive component of the
photoreceptor, the “phytochromobilin”. Incorporation of 15Ea-PCB
activates the photoreceptor and the plant is made believe it is exposed
to light. In spite of the darkness, model plants germinate and grow
similar to a control group exposed to light. “It was shown for the first
time that synthetic substances can cause light effects in entire
plants.”
Synthetic
photoreceptors might be valuable tools for research, as they facilitate
studies of many chemical plant processes compared to conventional
genetic engineering methods. Apart from growth, photosynthesis can also
be investigated much better.
“Blossoming
of flowers or development of the photosynthesis system may be
controlled much better in the future,” predicts Lamparter. “These
findings would be of high use for agricultural industry in the
cultivation of flowers or biomass production, for instance.” In the
future, it is planned to study related aspects in further detail.
