From the roots to the leaves: nicotianamine is crucial for zinc transport
For genetic reasons, plants contain very different amounts of minerals depending on their living environment. Arabidopsis halleri, for example, which is native to Germany, gathers a hundred times more zinc in its leaves than many other plants. In cooperation with colleagues from the University of Bayreuth, Krmer's team has contributed to showing how this functions: Arabidopsis halleri produces large amounts of nicotianamine. When the researchers deactivated the synthesis of this molecule by means of genetic manipulation, the plants also transported less zinc from the roots to the leaves. Nicotianamine is therefore crucial for the high zinc concentration in leaves. "In developing countries, zinc deficiency is one of the biggest dietary risk factors for health problems" Krmer explains. "Our data may provide important clues on how to breed crops with increased zinc content".
How copper gets into the plant cell
The Bochum biologists also researched how plant cells absorb copper together with American colleagues. For this, they employed what is known as next-generation sequencing. The method they employed simultaneously decodes all messenger RNAs within a cell. This gives a complete picture of what proteins the cell should produce in what quantities. From these data, Krmer's team identified new molecules with a critical role in the absorption of copper. The scientists demonstrated that the copper ions are first converted from the double positively charged cupric to the single positively charged cuprous form, which is essential for the following absorption in the plant. Two specific enzymes, called copper reductases, are responsible for this. "Independently of this, we have also discovered that copper deficiency in plants triggers a secondary iron deficiency contra
|Contact: Prof. Dr. Ute Krmer|