Examples of long-range gene regulation in bacteria are rare and generally thought to involve DNA looping. Here, using a combination of biophysical approaches including X-ray crystallography and single-molecule analysis for the KorB-KorA system in Escherichia coli, we show that long-range gene silencing on the plasmid RK2, a source of multi-drug resistance across diverse Gram-negative bacteria, is achieved cooperatively by a DNA-sliding clamp, KorB, and a clamp-locking protein, KorA. We show that KorB is a CTPase clamp that can entrap and slide along DNA to reach distal target promoters up to 1.
View Article and Find Full Text PDFBackground: Previous research has shown that females who use hormonal contraception are at increased risk of developing depression, and that the risk is highest among adolescents. While this finding could reflect age-specific effects of exogenous hormones on mental health, genetic liability for mental disorders could be confounding the association. Our goal was to test the plausibility of this hypothesis by determining whether polygenic liabilities for major depressive disorder (MDD), bipolar disorder (BD), schizophrenia (SCZ), and attention deficit hyperactivity disorder (ADHD) are associated with younger age at hormonal contraception initiation.
View Article and Find Full Text PDFFluoride-ion batteries have several potential advantages over lithium-ion batteries. Materials development is still needed, however, to realize electrolytes with sufficiently high anion conductivity and compatibility with anode and cathode layers. Fluoride compounds are difficult to synthesize directly as single crystals but can be realized from oxide film precursors via topotactic chemistry techniques.
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