Newly discovered calcium pumps: key to cellular communication!

Newly discovered calcium pumps: key to cellular communication!

The latest research into calcium transport mechanics in the human body could have far-reaching implications for medical science. An international team led by study leader Dr. Uwe Schulte from the University of Freiburg recently decoded the functional principle of the calcium pumps inside the cell. These pumps are crucial for regulating calcium levels, which are essential for both cellular communication and many physiological processes. The results of this study were published on August 20, 2025 in the specialist magazine Nature Communications published.

Calcium (approx²⁺) acts as both a nutrient and a signal in the body. To generate the correct signals for various physiological responses, precise calcium homeostasis is crucial. Calcium ATPase types in intracellular membranes have turnover rates of only a few tens of cycles per second. To measure calcium concentrations, the scientists used calcium-activated potassium channels as ultrafast sensors. In this way, they were able to precisely determine the transport speed of the calcium pumps.

Detailed results of the study

Electron microscopy of the cell membranes revealed densities of about 55 pump complexes per square micrometer. Interestingly, the calcium pumps interact with the membrane lipid PtdIns(4,5)P2, allowing rapid binding and release of calcium ions. Without this lipid binding, the transport process slows down significantly. Analyzes of mutations in the pump structure confirmed these findings.

Additionally, the researchers used thapsigargin, a known calcium pump inhibitor, to block the binding site of PtdIns(4,5)P2. This significantly limited pumping activity. These insights into the 3D structure of pump complexes and lipid-dependent regulation could provide promising approaches for new drugs to optimize calcium transport and signal processing, potentially treating diseases associated with calcium deficiency or excess.

Context and future perspectives

Calcium signaling is essential not only for humans but also for other eukaryotic organisms. Research results show that the transport mechanisms for Ca²⁺in the different eukaryotic kingdoms have evolved over evolution. These studies are important to understand the challenges and complexities of calcium signaling across specialized Ca²⁺-Binding proteins and signatures are defined. There are numerous national and international projects that deal with the basics of calcium transport and take into account comparative studies between fungi, animals and plants, such as PubMed reported.

The researchers involved come from several institutions, including the Max Planck Institute for Molecular Physiology. Prof. Dr. Bernd Fakler from the University of Freiburg, as well as his colleagues Prof. Dr. Stefan Raunser and Prof. Dr. Heiko Rieger, made a significant contribution to researching how the pumps work. Their work provides a comprehensive framework that opens both theoretical and practical insights into calcium signaling.