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Molecules that bind DNA by intercalating its bases remain among the most potent cancer therapies and antimicrobials due to their interference with DNA-processing proteins. To accelerate the discovery of novel intercalating drugs, we designed a fluorescence resonance energy transfer (FRET)-based probe that reports on DNA intercalation, allowing rapid and sensitive screening of chemical libraries in a high-throughput format. We demonstrate that the method correctly identifies known DNA intercalators in approved drug libraries and discover previously unreported intercalating compounds. When introduced in cells, the oligonucleotide-based probe rapidly distributes in the nucleus, allowing direct imaging of the dynamics of drug entry and its interaction with DNA in its native environment. This enabled us to directly correlate the potency of intercalators in killing cultured cancer cells with the ability of the drug to penetrate the cell membrane. The combined capability of the single probe to identify intercalators in vitro and follow their function in vivo can play a valuable role in accelerating the discovery of novel DNA-intercalating drugs or repurposing approved ones.

The widespread use of harmful fungicides in the agricultural sector has led to a demand for safer alternatives to protect against crop pathogens. The domestic apple is the second most highly consumed fruit in the world and encounters several pre- and post-harvest fungal and bacterial phytopathogens. The goal of this study was to explore the uncharacterized microbiome of a wild apple, Malus trilobata, as a potential source of novel biocontrol agents for two post-harvest fungi that affect commercial apples: Botrytis cinerea and Penicillium expansum. We sampled microflora associated with the leaves, bulk soil, and roots of Malus trilobata in two regions of Lebanon: Ehden reserve in the north and Dhour EL Choueir near Beirut. The two regions have different soil types Dhour EL Choueir and samples from the two regions showed very different microbial compositions, with greater microbial diversity among those from Ehden reserve. Molecular characterization revealed a wide variety of genera displaying activity against the two fungal pathogens, including several with previously unknown antifungal activity: Bosea, Microlunatus, Microbacterium, Mycetecola, Rhizobium and Paraphoma. In total, 92 strains inhibited Penicillium expansum (39%) and 87 strains inhibited Botrytis cinerea (38%) out of 237 screened. Further chemical and genetic characterization of one or more selected strains could pave the way for future development of new biocontrol agents for post-harvest applications.

High-content screening (HCS) uses microscopy images to generate phenotypic profiles of cell morphological data in high-dimensional feature space. While HCS provides detailed cytological information at single-cell resolution, these complex datasets are usually aggregated into summary statistics that do not leverage patterns of biological variability within cell populations. Here we present a broad-spectrum HCS analysis system that measures image-based cell features from 10 cellular compartments across multiple assay panels. We introduce quality control measures and statistical strategies to streamline and harmonize the data analysis workflow, including positional and plate effect detection, biological replicates analysis and feature reduction. We also demonstrate that the Wasserstein distance metric is superior over other measures to detect differences between cell feature distributions. With this workflow, we define per-dose phenotypic fingerprints for 65 mechanistically diverse compounds, provide phenotypic path visualizations for each compound and classify compounds into different activity groups.

We describe MIP-1 and MIP-2, novel paralogous C. elegans germ granule components that interact with the intrinsically disordered MEG-3 protein. These proteins promote P granule condensation, form granules independently of MEG-3 in the postembryonic germ line, and balance each other in regulating P granule growth and localization. MIP-1 and MIP-2 each contain two LOTUS domains and intrinsically disordered regions and form homo- and heterodimers. They bind and anchor the Vasa homolog GLH-1 within P granules and are jointly required for coalescence of MEG-3, GLH-1, and PGL proteins. Animals lacking MIP-1 and MIP-2 show temperature-sensitive embryonic lethality, sterility, and mortal germ lines. Germline phenotypes include defects in stem cell self-renewal, meiotic progression, and gamete differentiation. We propose that these proteins serve as scaffolds and organizing centers for ribonucleoprotein networks within P granules that help recruit and balance essential RNA processing machinery to regulate key developmental transitions in the germ line.

Molecules that bind DNA by intercalating its bases remain among the most potent cancer therapies and antimicrobials due to their interference with DNA-processing proteins. To accelerate the discovery of novel intercalating drugs, we designed a fluorescence resonance energy transfer (FRET)-based probe that reports on DNA intercalation, allowing rapid and sensitive screening of chemical libraries in a high-throughput format. We demonstrate that the method correctly identifies known DNA intercalators in approved drug libraries and discover previously unreported intercalating compounds. When introduced in cells, the oligonucleotide-based probe rapidly distributes in the nucleus, allowing direct imaging of the dynamics of drug entry and its interaction with DNA in its native environment. This enabled us to directly correlate the potency of intercalators in killing cultured cancer cells with the ability of the drug to penetrate the cell membrane. The combined capability of the single probe to identify intercalators

As a simple model organism, C. elegans plays an important role in gaining insight into the relationship between bodily thrashing forces and biological effects, such as disease and aging, or physical stimuli, like touch and light. Due to their similar length scale, microfluidic chips have been extensively explored for use in various biological studies involving C. elegans. However, a formidable challenge still exists due to the complexity of integrating external stimuli (chemical, mechanical or optical) with free-moving worms and subsequent imaging on the chip. In this report, we use a microfluidic device to partially immobilize a worm, which allows for measurements of the relative changes in the thrashing force under different assay conditions. Using a device adapted to the natural escape-like coiling response of a worm to immobilization, we have quantified the relative changes in the thrashing force during different developmental stages (L1, L3, L4, and young adult) and in response to various glucose concentrations and drug treatment. Our findings showed a loss of thrashing force following the introduction of glucose into a wild type worm culture that could be reversed upon treatment with the type 2 diabetes drug metformin. A morphological study of the actin filament structures in the body wall muscles provided supporting evidence for the force measurement data. Finally, we demonstrated the multiplexing capabilities of our device through recording the thrashing activities of eight worms simultaneously. The multiplexing capabilities and facile imaging available using our device open the door for high-throughput neuromuscular studies using C. elegans.

The widespread use of harmful fungicides in the agricultural sector has led to a demand for safer alternatives to protect against crop pathogens. The domestic apple is the second most highly consumed fruit in the world and encounters several pre- and post-harvest fungal and bacterial phytopathogens. The goal of this study was to explore the uncharacterized microbiome of a wild apple, Malus trilobata, as a potential source of novel biocontrol agents for two post-harvest fungi that affect commercial apples: Botrytis cinerea and Penicillium expansum. We sampled microflora associated with the leaves, bulk soil, and roots of Malus trilobata in two regions of Lebanon: Ehden reserve in the north and Dhour EL Choueir near Beirut. The two regions have different soil types Dhour EL Choueir and samples from the two regions showed very different microbial compositions, with greater microbial diversity among those from Ehden reserve. Molecular characterization revealed a wide variety of genera displaying activity against the two fungal pathogens, including several with previously unknown antifungal activity: Bosea, Microlunatus, Microbacterium, Mycetecola, Rhizobium and Paraphoma. In total, 92 strains inhibited Penicillium expansum (39%) and 87 strains inhibited Botrytis cinerea (38%) out of 237 screened. Further chemical and genetic characterization of one or more selected strains could pave the way for future development of new biocontrol agents for post-harvest applications.

[Abstract] Cucurbit[7]uril-modified iron-oxide nanoparticles (CB[7]NPs) were loaded with doxorubicin hydrochloride (Dox) and tested as a drug delivery system. Dox was found to interact with the carbonyl-rich rims of the CB[7] macrocycles adsorbed on the surface of the nanoparticles. The Dox-loaded nanoparticles (Dox@CB[7]NPs) were stable at room temperature and physiological pH and released their Dox cargo under acidic conditions, in the presence of glutathione, or with heating. Dox@CB[7]NPs reduced the viability of HeLa and three other cancer-derived cell lines in vitro at lower IC50 than free Dox. They were also nontoxic to C. elegans. The sensitivity of HeLa cells to Dox@CB[7]NPs was enhanced when the temperature was elevated by application of an alternating magnetic field. Thus, Dox@CB[7]NPs show promise as agents for the intracellular delivery of Dox to cancer cells, for the selective and controlled release of the drug, and, more generally, as a possible means of combining chemotherapeutic and hyperthermic treatment modalities. Al Jalila Foundation; AJF 201425 Al Jalila Foundation; AJF 201538