74,921 articles mezi dny 1.12.2019 a 31.12.2020

QRICH1 dictates the outcome of ER stress through transcriptional control of proteostasis

Tissue homeostasis is perturbed in a diversity of inflammatory pathologies. These changes can elicit endoplasmic reticulum (ER) stress, protein misfolding, and cell death. ER stress triggers the unfolded protein response (UPR), which can promote recovery of ER proteostasis and cell survival or trigger programmed cell death. Here, we leveraged single-cell RNA sequencing to define dynamic...

Seroprevalence of anti-SARS-CoV-2 IgG antibodies in Kenyan blood donors

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Africa is poorly described. The first case of SARS-CoV-2 in Kenya was reported on 12 March 2020, and an overwhelming number of cases and deaths were expected, but by 31 July 2020, there were only 20,636 cases and 341 deaths. However, the extent of SARS-CoV-2 exposure in the community remains unknown. We determined the...

Steps toward translocation-independent RNA polymerase inactivation by terminator ATPase {rho}

Factor-dependent transcription termination mechanisms are poorly understood. We determined a series of cryo–electron microscopy structures portraying the hexameric adenosine triphosphatase (ATPase) on a pathway to terminating NusA/NusG-modified elongation complexes. An open ring contacts NusA, NusG, and multiple regions of RNA polymerase, trapping and locally unwinding proximal upstream...

Structural basis of antagonizing the vitamin K catalytic cycle for anticoagulation

Vitamin K antagonists are widely used anticoagulants that target vitamin K epoxide reductases (VKOR), a family of integral membrane enzymes. To elucidate their catalytic cycle and inhibitory mechanism, we report 11 x-ray crystal structures of human VKOR and pufferfish VKOR-like, with substrates and antagonists in different redox states. Substrates entering the active site in a partially oxidized...