Proteins and other biopolymers can form in solution macrocomplexes, which at certain conditions are visible under the microscope («coacervate droplets»). The latter process is known to shape subcellular organization and for a century is considered to also impact plausible life-origin scenarios. Researchers from IBCh RAS and University of Vienna present a newly derived fractal model to describe atomistic structure of such protein condensates and using the N-terminal disordered fragment (80 residues) of the yeast transcription regulator Lge1 as a test system. The proposed theoretical model describes protein condensates across various scales in line with the general principles of colloidal system self-organization. The study combining complementary results of microsecond molecular dynamics simulations and in vitro biophysical experiments has been published in eLife. Learn more
- Open AccessArticle Galectin-9 as a Potential Modulator of Lymphocyte Adhesion to Endothelium via Binding to Blood Group H Glycan
Adhesion of leukocytes is a key stage in their trafficking into sites of inflammation. This process is mediated through the interaction of integrins, selectins or CD44, while the role of galectins is not completely clear. It is known that galectins are capable of interacting with oligolactosamines of endothelial cells, and also that in vitro tandem-type galectins (Gal-4, -8 and -9) bind with high affinity to glycans of the ABH blood group system. This work shows that in a cell lines system gal-9 mediates lymphocyte adhesion to endothelial cells through binding to their H-glycan, suggesting that lymphocyte adhesion to endothelium in the circulation occurs similarly and is regulated by the level of galectin-9 expression.
- Fractal droplets
Biological polymers (proteins, nucleic acids and their mixtures) are able to form macromolecular complexes in solution, which at a certain saturating concertation of a polymer grow in size and when crossing the diffraction limit (0.25 µm) become visible under the microscope. Such microscopically observed spherical liquid-like formations have various naming depending on a context such as: «coacervate droplets», biomolecular condensates, etc. Although these polymer droplets (especially proteinaceous) gained numerous attentions of scientist during the last century, e. g. as potential «protocells» in «the primordial soup» according to the life-origin hypothesis by Alexander Oparin, active studies of their functional roles in the living cells flourished in the recent decades.
- WINEGRET: а method for Wide-scale Identification of Novel and Eliminated Genes Responsible for Evolutionary Transformations
Scientists from the Laboratory of Molecular Bases of Embryogenesis at the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, in collaboration with researchers from the Kharkevich Institute for Problems of Information Transmission, Russian Academy of Sciences, have pioneered a method for wide-scale identification of genes whose loss or emergence during evolution correlates with the disappearance or emergence of distinct phenotypic or physiological traits.