Schlagwort: temperature
Thermogenetics: How Proteins Are Controllable by Heat
Protein activity can be precisely regulated via subtle changes in temperature using heat-sensitive switches. Underlying this capability is a novel modular design strategy developed by researchers at the Institute of Pharmacy and Molecular Biotechnology of Heidelberg University. The strategy allows the integration of sensory domains in various proteins regardless of function or spatial structure. This new Heidelberg approach in the field of thermogenetics is broadly applicable and opens up new possibilities for precise, non-invasive control of different cellular processes. Quelle: IDW Informationsdienst Wissenschaft
Implications of quantum metabolism and natural selection for the origin of cancer cells and tumor progression
Energy transfer in material solids is driven primarily by differences in intensive thermodynamic quantities such as pressure and temperature. The crucial observation in quantum-theoretical models was the consideration of the heat capacity as associated with the vibrations of atoms in a crystalline solid. However, living organisms are essentially isothermal. Because of very little differences in temperature between different parts of a cell it is assumed that energy flow in living organisms is mediated by differences in the turnover time of various metabolic processes in the cell, which occur in cyclical fashion. It has been shown that the cycle time of…
Three-dimensional super-resolution microscopy of the inactive X chromosome territory reveals a collapse of its active nuclear compartment harboring distinct Xist RNA foci
Daniel Smeets, Yolanda Markaki, Volker J Schmid, Felix Kraus, Anna Tattermusch, Andrea Cerase, Michael Sterr, Susanne Fiedler, Justin Demmerle, Jens Popken, Heinrich Leonhardt, Neil Brockdorff, Thomas Cremer1, Lothar Schermelleh and Marion Cremer Abstract Background A Xist RNA decorated Barr body is the structural hallmark of the compacted inactive X territory in female mammals. Using super-resolution three-dimensional structured illumination microscopy (3D-SIM) and quantitative image analysis, we compared its ultrastructure with active chromosome territories (CTs) in human and mouse somatic cells, and explored the spatio-temporal process of Barr body formation at onset of inactivation in early differentiating mouse embryonic stem cells (ESCs)….
The carcinogenic effect of various multi-walled carbon nanotubes (MWCNTs) after intraperitoneal injection in rats
Susanne Rittinghausen, Anja Hackbarth, Otto Creutzenberg, Heinrich Ernst, Uwe Heinrich, Albrecht Leonhardt and Dirk Schaudien Abstract Background Biological effects of tailor-made multi-walled carbon nanotubes (MWCNTs) without functionalization were investigated in vivo in a two-year carcinogenicity study. In the past, intraperitoneal carcinogenicity studies in rats using biopersistent granular dusts had always been negative, whereas a number of such studies with different asbestos fibers had shown tumor induction. The aim of this study was to identify possible carcinogenic effects of MWCNTs. We compared induced tumors with asbestos-induced mesotheliomas and evaluated their relevance for humans by immunohistochemical methods. Methods A total of 500…