Max Planck Institutes and Experts

In all cells of our bodies DNA is found complexed with basic proteins, the so-called histones. These proteins not only organize and protect the genetic information, but are also crucially involved in all biological processes involving DNA. In this aspect, a large number of different post-translational histone modifications direct the availability and accessibility of the DNA. While many histone modifications could be linked to different biological phenomena and signal transduction pathways, the molecular working mechanisms of most histone modifications are still not understood.

The cell nucleus is enclosed by the nuclear envelope, lacks protein synthesis and therefore imports each and every protein from the cytosol. Conversely, the nucleus supplies the cytoplasm with nuclear products, such as ribosomes, tRNAs and mRNAs. The permeability barrier of nuclear pore complexes controls all this exchange. This permeability barrier is an "intelligent" hydrogel with truly remarkable properties. It excludes inert macromolecules, but permits an up to 20 000-fold faster entry of cargoes, when these are bound to appropriate nuclear transport receptors.

Semiconductor chips and neuronal systems can be electrically coupled on a microscopic level. This research provides the fundament for an application of such hybrid processors in brain research, neuroprosthetics and information technology. On the neuronal side, ion channels, nerve cells and brain tissue are employed. On the electronic side, simple silicon chips with transistors and capacitors are used for the elucidation of the coupling mechanism. On that basis, complex chips are developed with more that 30000 contact sites to supervise neuronal activity with highest spatial resolution.

The structure of viruses provides a remarkable example of simplicity and functionality in biological systems. Composed of a limited number of proteins and often organized according to geometric principles, viral particles are effective devices in the transfer of the viral genome and proteins to host cells. To determine the molecular interactions, cryo electron tomography is employed to reveal the molecular players through which viruses communicate with their hosts and to understand how viruses take advantage of cellular cues in infection and for replicating themselves efficiently.

How are ecosystem functions influenced by the loss of species diversity? How does the presence or absence of particular species affect biogeochemical cycles? The group ‘Organismic Biogeochemistry’ addresses these questions by compiling and analyzing global databases of functional plant traits and ecosystem properties. Three examples are presented to show that species identity effects may influence the carbon cycles at large scales and may thus be relevant in the context of climate change.