Cholesterol-Modified Caged siRNAs for Photoregulating Exogenous and Endogenous Gene Expression

siRNA has been widely applied in research and drug development due to its sequence-specific gene silencing ability. However, how to spatiotemporally control its function is still one of its challenges. Light, a fast and noninvasive trigger, is a promising tool for spatiotemporal control of gene expression. Here, we designed and synthesized a new series of caged siRNAs modified with single cholesterol at the 5′ terminal of antisense strand RNA through a photolabile linker (Chol-PL-siRNAs). We demonstrated that these caged siRNAs were successfully used to photochemically regulate both exogenous (<i>firefly luciferase</i> and <i>gfp</i>) and endogenous gene expression (mitotic kinesin-5, <i>Eg5</i>) in cells

Fate of fenoxaprop-ethyl and fenoxaprop

Concentration and SD of fenoxaprop-ethyl and fenoxaprop in control and biochar-amended soils during the incubatio

Vitamin E‑Labeled Polyethylenimine for <i>in vitro</i> and <i>in vivo</i> Gene Delivery

A series of Vitamin E (vitE)-labeled PEIs (PEI-vitE_<i>n</i>) were synthesized and showed excellent complexation ability with plasmid DNA (pDNA). The cellular uptake of PEI-vitE_<i>n</i>/pDNA complexes was greatly enhanced with the increase of vitE labeling, which is much better than that of control PEI25 in three different cell lines. PEI-vitE₆ showed the best performance in <i>gfp</i> pDNA delivery and following GFP expression in HEK-293A cells. In addition, <i>in vivo</i> gene delivery in living mice also confirmed that PEI-vitE₆ showed low toxicity and efficiently delivered <i>gfp</i> pDNA to the cells of liver and lung tissues for gene expression

Oxidation-Induced Topological Phase Transition in Monolayer 1T′-WTe₂

Monolayer (ML) tungsten ditelluride (WTe₂) is a well-known quantum spin Hall (QSH) insulator with topologically protected gapless edge states, thus promising dissipationless electronic devices. However, experimental findings exhibit the fast oxidation of ML WTe₂ in ambient conditions. To reveal the changes of topological properties of WTe₂ arising from oxidation, we systematically study the surface oxidation reaction of ML 1T′-WTe₂ using first-principles calculations. The calculated results indicate that the fast oxidation of WTe₂ originates from the existence of H₂O in air, which significantly promotes the oxidation of ML 1T′-WTe₂. More importantly, this low-coverage oxidized WTe₂ loses its topological features and is changed into a trivial insulator. Furthermore, we propose a fully oxidized ML WTe₂ that can still possess the QSH insulator states. The topological phase transition induced by oxidation provides exotic insight into understanding the topological features of layered transition-metal dichalcogenide materials