How do plants deal with iron deficiency?

Iron is an essential nutrient for plants, animals and also for humans. It is necessary for a wide range of metabolic processes, for example for photosynthesis and respiration. If a person lacks iron, it will have a major negative impact on health. Millions of people around the world suffer from iron deficiency each year. Iron enters the human food chain through plants directly or indirectly. Although the soil usually contains large amounts of iron, the plants may become deficient in iron because of the specific soil composition. In addition, the iron requirements of a plant vary during its development depending on external circumstances.

Because plants are sessile, they can not escape their respective situations. As a result, they have developed strategies to recognize and adapt to changing environmental conditions at an early stage. Particularly in light of climate change, understanding the process used by plants to adapt to changes in food availability when environmental factors become unpredictable is also of major importance for the agricultural sector and its research partners in their efforts to create new varieties of high-yield products. cultivated plants.

Iron regulation is an important model system in plant biology to understand the impact of cellular regulation processes on badociated signaling pathways. HHU researchers, under the direction of Professor Petra Bauer and her badociate, Dr. Tzvetina Brumbarova, and WWU, under the direction of MM. Jörg Kudla and Uwe Karst, have examined the particular mechanisms and dynamics of a protein named "FIT" in iron and have discovered the cellular information processes that have an impact on FIT.

The FIT protein has been discovered by Professor Bauer's working group and its regulatory mechanisms are being examined at the HHU Botanical Institute. FIT may be present in an active or inactive state. In the model plant Arabidopsis thaliana, it plays a key role in the regulation of iron absorption. How does the plant decide how much iron to absorb, and how is this information transmitted to the FIT regulator being researched at HHU? The FIT control mechanism described in Düsseldorf combines different signals used by the plant to respond to environmental conditions and stress conditions.

Plant-based biologists based in Münster, in collaboration with Professor Kudla of the Institute of Plant Biology and Biotechnology, are specialized in understanding what is called "cell signal transduction", in particular the signal transduction of calcium. This involves a signal transmission by which the plant converts and transmits environmental information and triggers stress reactions, for example – or, as demonstrated in this case, a better response to iron deficiency. To this end, the team at the Institute of Inorganic and Analytical Chemistry WWU, led by Professor Karst, badyzed the concentration of iron in plants.

Until now, the precise link between iron and calcium was not clear. Now, research teams at HHU and WWU have discovered that iron deficiency triggers calcium signals, which has a significant influence on the regulatory mechanism of FIT. In the joint study published in Developmental cell, the research teams describe how the CIPK11 enzyme linked to calcium detection can interact with the FIT protein and label it. In the end, the plant can use this FIT activation to control iron absorption through its roots and iron storage in its seeds.

"We have been able to detect the molecular and cellular mechanisms that link FIT to the decoding of calcium signals, which is important when the plant has to control the absorption of iron according to external factors," explain Dr. Brumbarova and Prof. Bauer. Professor Kudla added, "Our discovery has implications for both biological and medical issues related to nutrients, developmental processes and stress behaviors."

This article has been republished from material provided by the Heinrich Heine University of Düsseldorf. Note: Content may have changed for length and content. For more information, please contact the cited source.

Reference: Regina Gratz et al. 2019. CIPK11-dependent phosphorylation modulates the activity of FIT to promote the acquisition of iron from Arabidopsis in response to calcium signaling. Developmental Cell http://dx.doi.org/10.1016/j.devcel.2019.01.006.