Applications of porous metal-organic frameworks (MOFs) in electronic devices are rare, owing in large part to a lack of MOFs that display electrical conductivity. Here, we describe the use of conductive two-dimensional (2D) MOFs as a new class of materials for chemiresistive sensing of volatile organic compounds (VOCs). We demonstrate that a family of structurally analogous 2D MOFs can be used to construct a cross-reactive sensor array that allows for clear discrimination between different categories of VOCs. Experimental data show that multiple sensing mechanisms are operative with high degrees of orthogonality, establishing that the 2D MOFs used here are mechanistically unique and offer advantages relative to other known chemiresistor materials.

A deficient interferon response to SARS-CoV-2 infection has been implicated as a determinant of severe COVID-19. To identify the molecular effectors that govern interferon control of SARS-CoV-2 infection, we conducted a large-scale gain-of-function analysis that evaluated the impact of human interferon stimulated genes (ISGs) on viral replication. A limited subset of ISGs were found to control viral infection, including endosomal factors inhibiting viral entry, RNA binding proteins suppressing viral RNA synthesis, and a highly enriched cluster of ER-Golgi-resident ISGs inhibiting viral assembly-egress. These included broad-acting antiviral ISGs, and eight ISGs that specifically inhibited SARS-CoV-2 and -1 replication. Amongst the broad-acting ISGs was BST2/tetherin, which impeded viral release, and is antagonized by SARS-CoV-2 Orf7a protein. Overall, these data illuminate a set of ISGs that underlie innate immune control of SARS-CoV-2/-1 infection, which will facilitate the understanding of host determinants that impact disease severity and offer potential therapeutic strategies for COVID-19.

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Over the past decade, metal-organic frameworks (MOFs) have provided an excellent platform for engineering functional materials through judicious choices of the constituent building blocks. Numerous MOFs have been synthesized, and some of them have been explored for potential applications such as gas storage, [1] chemical sensing, [2] catalysis, [3] biomedical imaging, [4] and drug delivery. [5] Catalytic MOFs having imbedded, well-defined active sites are of particular interest owing to their utility as recyclable and reusable catalysts. Because of their highly ordered and typically crystalline structures, MOF catalysts can in principle be characterized by X-ray diffraction methods to provide precise structural information on the catalytic active sites, thus allowing the delineation of catalyst structure-function relationships.[6]Herein we report the first observation of the actuation of a MOF catalyst through a reversible single-crystal to singlecrystal reduction process.Among many strategies for synthesizing catalytic MOFs, direct incorporation of catalytically competent building blocks into the MOF frameworks has recently emerged as a powerful approach toward building highly active and selective solid catalysts. [3,7] Motivated by excellent asymmetric catalytic activities exhibited by many homogeneous metal/salen complexes [where an archetypical chiral salen ligand is (R,R)-1,2-cyclohexanediamino-N,N'-bis(3-tert-butyl-salicylidene)], [8] MOFs containing metal/salen building blocks have attracted a great deal of recent interest.[9] Whereas some of the chiral metal/salen-based MOFs have shown promise in chiral recognition and separation, [10] two manganese/salen-derived MOF systems have recently been shown to be excellent asymmetric alkene epoxidation catalysts. [11] In this work, a pair of interpenetrated and non-interpenetrated chiral MOFs (CMOFs) of the primitive cubic unit (pcu) topology were constructed from redox active ruthenium/salen-based bridging ligands and [Zn 4 (m 4 -O)(O 2 CR) 6 ] secondary building units (SBUs). These CMOFs showed the first example of reversible single-crystal to single-crystal reduction/reoxidation behavior. Although a few examples of single-crystal to single-crystal oxidation of MOFs were reported, none of these redox reactions were demonstrated to be reversible. [12] In contrast, the reduction of a MOF was recently elucidated by a Rietveld analysis of powder X-ray diffraction data.[13] We report here that upon single-crystal to single-crystal reduction, catalytically inactive Ru III -based CMOFs were activated to form Ru II -based MOF catalysts for the asymmetric cyclopropanation of styrene and other substituted alkenes with very high diastereo-and enantioselectivities (d.r. = 7:1 and ee = 91 %). The catalytic activity of the CMOFs is catenation dependent: the non-interpenetrated CMOF is highly active whereas the interpenetrated CMOF is nearly inactive. We also show that the CMOFs maintain their crystallinity, and less than 0.01 % of the ruthenium/salen catalyst leached int...

Mapping protein interactions driving cancer Cancer is a genetic disease, and much cancer research is focused on identifying carcinogenic mutations and determining how they relate to disease progression. Three papers demonstrate how mutations are processed through networks of protein interactions to promote cancer (see the Perspective by Cheng and Jackson). Swaney et al . focus on head and neck cancer and identify cancer-enriched interactions, demonstrating how point mutant–dependent interactions of PIK3CA, a kinase frequently mutated in human cancers, are predictive of drug response. Kim et al . focus on breast cancer and identify two proteins functionally connected to the tumor-suppressor gene BRCA1 and two proteins that regulate PIK3CA. Zheng et al . developed a statistical model that identifies protein networks that are under mutation pressure across different cancer types, including a complex bringing together PIK3CA with actomyosin proteins. These papers provide a resource that will be helpful in interpreting cancer genomic data. —VV