RNAs undergo a complex choreography of metabolic processes in human cells that are regulated by thousands of RNA-associated proteins. While the effects of individual RNA-associated proteins on RNA metabolism have been extensively characterized, the full complement of regulators for most RNA metabolic events remain unknown. Here we present a massively parallel RNA-linked CRISPR (ReLiC) screening approach to measure the responses of diverse RNA metabolic events to knockout of 2,092 human genes encoding all known RNA-associated proteins.
View Article and Find Full Text PDFSF3B1 splicing factor mutations are near-universally found in myelodysplastic syndromes (MDS) with ring sideroblasts (RS), a clonal hematopoietic disorder characterized by abnormal erythroid cells with iron-loaded mitochondria. Despite this remarkably strong genotype-to-phenotype correlation, the mechanism by which mutant SF3B1 dysregulates iron metabolism to cause RS remains unclear due to an absence of physiological models of RS formation. Here, we report an induced pluripotent stem cell model of SF3B1-mutant MDS that for the first time recapitulates robust RS formation during in vitro erythroid differentiation.
View Article and Find Full Text PDFEfforts to battle antimicrobial resistance (AMR) are generally focused on developing novel antibiotics. However, history shows that resistance arises regardless of the nature or potency of new drugs. Here, we propose and provide evidence for an alternate strategy to resolve this problem: inhibiting evolution.
View Article and Find Full Text PDFWe previously reported that lagging-strand genes accumulate mutations faster than those encoded on the leading strand in Bacillus subtilis. Although we proposed that orientation-specific encounters between replication and transcription underlie this phenomenon, the mechanism leading to the increased mutagenesis of lagging-strand genes remained unknown. Here, we report that the transcription-dependent and orientation-specific differences in mutation rates of genes require the B.
View Article and Find Full Text PDFThe nonsense-mediated mRNA decay (NMD) pathway selectively eliminates aberrant transcripts containing premature translation termination codons and regulates the levels of a number of physiological mRNAs. NMD modulates the clinical outcome of a variety of human diseases, including cancer and many genetic disorders, and may represent a target for therapeutic intervention. Here, we have developed a new multicolored bioluminescence-based reporter system that can specifically and effectively assay NMD in live human cells.
View Article and Find Full Text PDFSquare grid coordination polymers (CPs) based upon four-connected metal centres linked by linear bifunctional ligands such as 4,4'-bipyridine were first reported in 1990 and the study of their pillared variants began in 1995. It was quickly realized by crystal engineers that the modularity of such CPs creates families of related compounds or platforms which in turn affords opportunities for systematic study of structure/function relationships in the context of catalysis, magnetism and porosity. This review covers the historical development of this important class of CPs before addressing recent studies of variants which incorporate 4,4'-bipyridine and related linkers to facilitate control over pore size and inorganic anion pillars to enable strong interactions with polarizable molecules such as CO2.
View Article and Find Full Text PDFWe report MPM-1-TIFSIX, a molecular porous material (MPM) based upon the neutral metal complex [Cu2(adenine)4(TiF6)2], that self-assembles through a hydrogen-bonding network. This MPM is amenable to room-temperature synthesis and activation. Gas adsorption measurements and ideal adsorbed solution theory selectivity predictions at 298 K revealed enhanced CO2 separation performance relative to a previously known variant as well as the highest CO2 uptake and isosteric heat of adsorption yet reported for an MPM.
View Article and Find Full Text PDFThe energy costs associated with the separation and purification of industrial commodities, such as gases, fine chemicals and fresh water, currently represent around 15 per cent of global energy production, and the demand for such commodities is projected to triple by 2050 (ref. 1). The challenge of developing effective separation and purification technologies that have much smaller energy footprints is greater for carbon dioxide (CO2) than for other gases; in addition to its involvement in climate change, CO2 is an impurity in natural gas, biogas (natural gas produced from biomass), syngas (CO/H2, the main source of hydrogen in refineries) and many other gas streams.
View Article and Find Full Text PDFPillar substitution in a long-known metal-organic material with saturated metal centres, [Cu(bipy)(2)(SiF(6))](n), has afforded the first crystallographically characterized porous materials based upon TiF(6)(2-) and SnF(6)(2-) anions as pillars. Gas adsorption studies revealed similar surface areas and adsorption isotherms but enhanced selectivity towards CO(2)vs. CH(4) and N(2).
View Article and Find Full Text PDFThis year the government aggressively pursued Manufacturers under the enhanced provisions of the False Claims Act (FCA), as well as under the provisions of the Food, Drug and Cosmetics Act (FDCA). In addition, the government pursued actions against individual executives under the Responsible Corporate Officer Doctrine ("RCO Doctrine") because it does not believe sanctions against the companies provide sufficient deterrence to inappropriate behavior. Companies need to focus on implementing effective compliance programs in order to prevent the occurrence of allegedly improper activity.
View Article and Find Full Text PDFReaction of biphenyl-3,4',5-tricarboxylate (H(3)BPT) and CdCl(2) in the presence of meso-tetra(N-methyl-4-pyridyl)porphine tetratosylate (TMPyP) afforded porph@MOM-10, a microporous metal-organic material containing CdTMPyP cations encapsulated in an anionic Cd(II) carboxylate framework, [Cd(6)(BPT)(4)Cl(4)(H(2)O)(4)]. Porph@MOM-10 is a versatile platform that undergoes exchange to serve as the parent of a series of porph@MOMs that exhibit permanent porosity and heterogeneous catalytic activity.
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