Joint figures of training along with entropy generation along quantum trajectories

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No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).Vascular dysfunction is a typical characteristic of aging, but its contributing roles to systemic aging and the therapeutic potential are lacking experimental evidence. Here, we generated a knock-in mouse model with the causative Hutchinson-Gilford progeria syndrome (HGPS) LmnaG609G mutation, called progerin. The Lmnaf/f ;TC mice with progerin expression induced by Tie2-Cre exhibit defective microvasculature and neovascularization, accelerated aging, and shortened life span. Single-cell transcriptomic analysis of murine lung endothelial cells revealed a substantial up-regulation of inflammatory response. Molecularly, progerin interacts and destabilizes deacylase Sirt7; ectopic expression of Sirt7 alleviates the inflammatory response caused by progerin in endothelial cells. Vascular endothelium-targeted Sirt7 gene therapy, driven by an ICAM2 promoter, improves neovascularization, ameliorates aging features, and extends life span in Lmnaf/f ;TC mice. These data support endothelial dysfunction as a primary trigger of systemic aging and highlight gene therapy as a potential strategy for the clinical treatment of HGPS and age-related vascular dysfunction. Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).Previous research has shown that modern Eurasians interbred with their Neanderthal and Denisovan predecessors. We show here that hundreds of thousands of years earlier, the ancestors of Neanderthals and Denisovans interbred with their own Eurasian predecessors-members of a "superarchaic" population that separated from other humans about 2 million years ago. The superarchaic population was large, with an effective size between 20 and 50 thousand individuals. We confirm previous findings that (i) Denisovans also interbred with superarchaics, (ii) Neanderthals and Denisovans separated early in the middle Pleistocene, (iii) their ancestors endured a bottleneck of population size, and (iv) the Neanderthal population was large at first but then declined in size. We provide qualified support for the view that (v) Neanderthals interbred with the ancestors of modern humans. Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).By hijacking endogenous E3 ligase to degrade protein targets via the ubiquitin-proteasome system, PROTACs (PRoteolysis TArgeting Chimeras) provide a new strategy to inhibit protein targets that were regarded as undruggable before. However, the catalytic nature of PROTAC potentially leads to uncontrolled degradation that causes systemic toxicity issues, limiting the application of PROTAC in the clinic. Here, we introduce a light-inducible switch on PROTACs, thereafter termed as opto-PROTAC, to enable the degradation of protein targets in a spatiotemporal manner. By adding a photolabile caging group on pomalidomide as a parental compound and two additional PROTACs, dBET1 and dALK, we demonstrated light-inducible protein degradation. These opto-PROTACs display no activities in the dark, while the restricted degradation can be induced at a specific time and rate by ultraviolet A irradiation. Our approach provides a generalizable platform for the development of light-controlled PROTACs and enables PROTAC to be a precision medicine. Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).PROTACs (PROteolysis TArgeting Chimeras) are bifunctional molecules that target proteins for ubiquitylation by an E3 ligase complex and subsequent degradation by the proteasome. They have emerged as powerful tools to control the levels of specific cellular proteins. We now introduce photoswitchable PROTACs that can be activated with the spatiotemporal precision that light provides. These trifunctional molecules, which we named PHOTACs (PHOtochemically TArgeting Chimeras), consist of a ligand for an E3 ligase, a photoswitch, and a ligand for a protein of interest. Eganelisib We demonstrate this concept by using PHOTACs that target either BET family proteins (BRD2,3,4) or FKBP12. Our lead compounds display little or no activity in the dark but can be reversibly activated with different wavelengths of light. Our modular approach provides a method for the optical control of protein levels with photopharmacology and could lead to new types of precision therapeutics that avoid undesired systemic toxicity. Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).Transcription factors comprise a major reservoir of conformational disorder in the eukaryotic proteome. The hematopoietic master regulator PU.1 presents a well-defined model of the most common configuration of intrinsically disordered regions (IDRs) in transcription factors. We report that the structured DNA binding domain (DBD) of PU.1 regulates gene expression via antagonistic dimeric states that are reciprocally controlled by cognate DNA on the one hand and by its proximal anionic IDR on the other. The two conformers are mediated by distinct regions of the DBD without structured contributions from the tethered IDRs. Unlike DNA-bound complexes, the unbound dimer is markedly destabilized. Dimerization without DNA is promoted by progressive phosphomimetic substitutions of IDR residues that are phosphorylated in immune activation and stimulated by anionic crowding agents. These results suggest a previously unidentified, nonstructural role for charged IDRs in conformational control by mitigating electrostatic penalties that would mask the interactions of highly cationic DBDs.