Researchers from Washington State University (WSU) led by biologist Helmut
Kirchhoff have found the mechanism by which plants heal from the botanical
equivalent of a bad sunburn. Kirchhoff said plants are continuously exposed
to solar damage. While the process produces energy for plants, it also
creates modified oxygen molecules, called reactive oxygen species or ROS,
that can damage proteins and other important plant molecules.

Kirchhoff and his colleagues worked on a specialized system of
photosynthetic membranes inside the chloroplast, which converts sunlight to
energy. The membranes contain sophisticated molecular-scale nanomachines
that are the prime target of oxidative damage. Other nanomachines can repair
the damage.

Previous studies found that the machines make repairs in multiple steps,
with each step dependent on the success of its predecessor. The research
team determined that the required order of steps is established by
separating different repair proteins from different membrane regions. This
compartmentalization is guaranteed by folding of the membrane. This insight
could help scientists generate plant mutations with membrane architectures
that make more efficient repairs, said Kirchhoff. "It could be good to
improve the repair machinery in hot and bright climates," he said.

[news.wsu.edu]
<[news.wsu.edu]
air/#.VEW19SKUeSo>