2023

Since 2022, the Fondation Bettencourt Schueller has launched a new program to support great talents in life sciences research: Impulscience®. Each year, Impulscience awards seven grants and IBS is proud to count two recipients among its researchers: Malene Jensen, 2022 laureate, and Rebekka Wild, 2023 laureate. To celebrate this success and highlight their research projects, a ceremony was held at the IBS on December 13, 2023, in the presence of Armand de Boissière, General Secretary of the (...)

A model for the genome organisation of the virus responsible for influenza is proposed on the basis of a tool developed from recombinant viral nucleoprotein and synthetic RNA. In an article published in the journal Science Advances, scientists used cryo-electron microscopy to study the assembly of the influenza nucleoprotein into a helix, thereby providing details of the protein-protein and protein-RNA interactions within the nucleocapsid. Since October 2021, Europe is suffering the most (...)

Photolyase is an enzyme harnessing visible light to repair a DNA strand that has been damaged by UV light. In a study published in Science, researchers have used X-rays from free electron lasers to reveal the atomic details of the molecular repair mechanism of a damaged DNA strand. To do this, they have used time-resolved crystallography on a time scale from hundreds of picoseconds to hundreds of microseconds. Antoine Royant and Sylvain Engilberge, from the Synchrotron group of the IBS, (...)

Rebekka Wild, team leader in the "Structure and activity of glycosaminoglycans" group at IBS, has been awarded the Impulscience® grant by the Bettencourt Schueller Foundation for her work wich aims to better understand the biosynthesis of these long sugar chains. Understanding better the biosynthesis of these chains will help to develop drugs that modify the structure of these long sugar chains and thus protect cells against viral infections or cancer ( (...)

Seedling roots, post-germination, need to grow quickly to anchor the growing plant in the soil. However, the growth is regulated by ascertaining that the environment is satisfactory for the plant. When encountering a stress in the soil, roots have a very limited number of options: it can stop growing, it can develop secondary roots, it can change direction. Often, all these options are combined. Plant roots grow by cell division and cell elongation. One or both processes can be altered (...)

The European Research Council (ERC) has just awarded an Advanced Grant to Jérôme Boisbouvier, a researcher at the Grenoble Institute de Biologie Structurale (IBS/Biomolecular NMR Spectroscopy Group), to develop new routes to study extra-large biomolecular assemblies using solution-state NMR. To know more

During meiosis, the formation of DNA double-strand breaks by the catalytic complex SPO11/TOPOVIBL and their repair through meiotic recombination are crucial mechanisms for the precise segregation of homologous chromosomes and the formation of gametes. However, the formation of these breaks can be dangerous and lead to undesirable chromosomal rearrangements if they are not introduced at the appropriate time and repaired correctly. Therefore, the activity of the SPO11-TOPOVIBL complex is (...)

Avian influenza viruses represents a recurring threat to human health. In particular highly pathogenic zoonotic avian strains, such as the currently circulating H5N1, can adapt to infect humans with high mortality, posing a catastrophic pandemic threat. Host adaptation is necessary for efficient replication and sustained human-to-human transmission. Amongst other adaptations, efficient replication in human cells requires mutations on the surface of the viral polymerase - the machine (...)

Researchers at the Institute of Structural Biology (IBS), in collaboration with the Laboratory of Metal Chemistry and Biology (LCBM), are investigating how the immune system responds when it encounters a threat. They are studying how certain substances, known as "alarmins," communicate with the complement defense system to alert and assist in repairing damage once the threat is under control. In their work, they are focusing on HMGB1, a protein normally located in the cell nucleus. However, (...)

The order Bunyavirales includes a large number of viruses that have a segmented negative-stranded RNA genome (sNSV). Divided into 12 families, some Bunyaviruses are major human pathogens, such as Lassa virus and Crimean Congo virus. Other viruses are emerging, such as Hantaviruses, which mainly infect arthropods and rodents, but can also infect humans, causing encephalitis or haemorrhagic fevers. There are currently no drugs or vaccines available to counter these viruses. In this context, (...)

Structural biology methods have often benefited from their cryogenic version. X-ray crystallography and electron microscopy have been revolutionized by the possibility to flash cool biological samples, reducing radiation damage or better preserving the native state of the investigated macromolecules, respectively. With the development of super-resolution microscopy (nanoscopy), the question now arises of moving towards cryo-nanoscopy. The approach has already been demonstrated by several (...)

Modifications in the exposure of molecules at surface of abnormal cells, or those dying by apoptosis, ordinarily lead to their elimination by macrophages (phagocytosis). These changes are impaired in the tumor context and this can impede phagocytosis and cause resistances to therapies. Using super-resolution fluorescence microscopy, also known as nanoscopy, because it can achieve a resolution of a few nanometers, researchers of the IBS/I2SR group have studied the distribution, diffusion (...)

Single-molecule localization microscopy (SMLM) is the most popular super-resolution fluorescence imaging technique. It is also the technique providing the best resolution enhancement, therefore being most suited for integrating structural biology into the cellular context. Like all super-resolution methods, SMLM fundamentally relies on specific fluorophore photophysical properties, like photoswitching. Its limitations, however, are also largely bound to –unwanted- fluorophore photophysics. (...)

Liquid-liquid phase separation, a ubiquitous phenomenon underlying the formation of membraneless compartments, is currently revolutionizing our understanding of cell biology. Flexible molecules, such as intrinsically disordered proteins (IDPs) are essential to maintaining the liquid properties of these highly concentrated organelles. Understanding the modulation of the structural and dynamic properties of these proteins upon phase transformation is essential to understanding this ubiquitous (...)

Pathogenic bacteria are becoming increasingly resistant to antibiotics. Alternatives must be found and validated to avoid falling back into the pre-antibiotic era. The use of bacteriophages, natural enemies of bacteria, is one of the most promising alternatives, both in agriculture/veterinary medicine and in human health. 60% of known phages consist of a capsid protecting the viral DNA and a long flexible tail, which serves to recognise the host via one or more receptor binding proteins (...)

Congratulations to the "Entry and budding of enveloped viruses group" labelled ’FRM 2023 group’ for its project "Structure and function of ESCRT-III polymers” The prestigious "FRM team" label is awarded for three years and finances innovative work in biology and health. The research program of Winfried Weissenhorn’s group aims to understand the structural and function of “endosomal sorting complexes required for transport” (ESCRT), a highly conserved membrane remodeling machinery present in all (...)

Fluorescent proteins are widely used in biological research to make all kinds of cell types or structures visible. A research team from the University of Amsterdam has developed a new bright red fluorescent protein, mScarlet3, which combines maximum brightness with fast and complete folding. They sent their creation to the Institut de Biologie Structurale in Grenoble, where structural biologist Antoine Royant mapped the molecular structure of the protein, using the European Synchrotron (...)

From Galileo Galilei and Robert Hooke in the 17th century to David Julius and Ardem Patapoutian, who won the 2021 Nobel Prize in Physiology or Medicine, stiffness and elasticity have been a cornerstone of classical physics and now in biology. To characterize a mechanical role in biology, one task is to quantify the elasticity of a sample. In common terms, the elasticity of a material is characterized by measuring its stiffness, or the resistance of an object to the deformation under an (...)

HSP90 is a fundamental chaperone protein for many cellular processes. Through its involvement in the folding of many oncoproteins, it is a therapeutic target against cancer. HSP90 is affected by complex structural rearrangements associated with ATP binding and hydrolysis during its functional cycle. However, these structural rearrangements remain poorly described for the apo protein. In this study, researchers from IBS and ILM-Lyon have, for the first time, identified a metastable excited (...)

The C-type lectin receptor DC-SIGN has been highlighted as co-receptor for the spike protein of the SARS-CoV-2 virus. A multivalent glycomimetic ligand, Polyman26, has been found to inhibit DC-SIGN-dependent trans-infection of SARS-CoV-2. The molecular details underlying avidity generation in such systems remain poorly characterized. In an effort to dissect the contribution of the known multivalent effects - chelation, clustering and statistical rebinding –, researcher of the IBS in Grenoble (...)