Cellular Stress Management in People and Plants
Cellular Stress Management in People
and Plants
Proteins have many tasks to
fulfil in the structure, function and regulation of cells. Once the proteins
are formed, they are further adapted for their very specific jobs. "One of
the most frequent changes is the attachment of an acetic acid residue on the
amino-terminal end of the proteins. Lacking this modification, the plants
cannot survive, and this same lack in certain proteins in humans leads to
illness, developmental problems and cell death," explains Prof. Hell.
Although up to 80 percent of proteins in the cytoplasm of human cells are
modified by an acetic acid residue at their amino terminus, the function of
this modification has only been studied for a handful of proteins.
The Heidelberg researchers
generated genetically modified plants with protein populations that carry less
acetic acid residues and analyzed the results. "The changed pattern of
amino-terminal modification proteins by acetic acid surprisingly made the
genetically modified plants proved to be more drought-resistant,"
continues Dr. Wirtz. The reason turned out to be mediated by the plant hormone
abscisic acid, a key player in drought stress. The drought resistance was based
on the constant activation of natural plant processes to counteract the stress,
such as closing the stomata and lengthening the primary root.