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[
Curr Biol,
2006]
Major sperm protein, a cytoskeletal molecule required for the amoeboid motility of sperm in Caenorhabditis elegans, also functions as a signaling molecule that regulates the rates of meiotic maturation and ovulation. Recent work has begun to uncover new genes required for the response to this signal in both somatic and germ line cells.
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[
Methods Mol Biol,
2024]
Intracellular transport of organelles and biomolecules is vital for several cellular processes. Single-molecule fluorescence microscopy can illuminate molecular aspects of the dynamics of individual biomolecules that remain unresolved in ensemble experiments. For example, studying single-molecule trajectories of moving biomolecules can reveal motility properties such as velocity, diffusivity, location and duration of pauses, etc. We use single-molecule imaging to study the dynamics of microtubule-based motor proteins and their cargo in the primary cilia of living C. elegans. To this end, we employ standard fluorescent proteins, an epi-illuminated, widefield fluorescence microscope, and primarily open-source software. This chapter describes the setup we use, the preparation of samples, a protocol for single-molecule imaging in primary cilia of C. elegans, and data analysis.
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Edison, Arthur S., Nocilla, Kelsey A., Van der Gaag, Victoria L., Asif, Muhammad Zaka, Muzio, Cole J., Guo, Jane
[
MicroPubl Biol,
2021]
1-Hydroxyphenazine (1-HP) is a small molecule produced by Pseudomonas aeruginosa, a bacterium that is used for pathogenesis models in C. elegans (Cezairliyan et al., 2013; Mahajan-Miklos, Tan, Rahme, & Ausubel, 1999). 1-HP is an especially interesting toxin to study as it has been shown to interact with human cells causing ciliary-slowing associated with dyskinesia and ciliostasis (Wilson et al., 1987). Prior research in our lab has shown that this molecule is toxic to C. elegans, with an LD50 between 150 and 200 M, but C. elegans can glycosylate 1-HP, which detoxifies the molecule (Stupp et al., 2013).
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[
Nature Neuroscience,
2002]
A molecule that may be important for sorting presynaptic components into the developing axon is now revealed by a study using the genetic tools available in C. elegans.
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[
Nat Chem Biol,
2011]
The DAF-9 cytochrome P450 is a key regulator of dauer formation, developmental timing and longevity in the nematode Caenorhabditis elegans. Here we describe the first identified chemical inhibitor of DAF-9 and the first reported small-molecule tool that robustly induces dauer formation in typical culture conditions. This molecule (called dafadine) also inhibits the mammalian ortholog of DAF-9(CYP27A1), suggesting that dafadine can be used to interrogate developmental control and longevity in other animals.
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[
Nature,
2000]
A tiny RNA molecule ensures that the larvae of a roundworm develop into adults. The discovery of this RNA in many other animal groups implies that this way of keeping developmental time may be universal.
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[
Curr Biol,
2020]
Recognizing and remembering dangerous pathogens is of the utmost importance for an animal's survival. Nematodes use a digested bacterial small RNA molecule as a cue of pathogenicity. Inheritance of this RNA even protects the progeny from infection.
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[
East Coast Worm Meeting,
2000]
We are investigating the molecular mechanisms underlying the process of RNA-mediated interference (RNAi). In C.elegans, introduction of double-stranded RNA (dsRNA) results in the post-transcriptional silencing of genetic loci containing homologous sequences. To achieve RNAi, only a few molecules of dsRNA are required to trigger an effect. Importantly, similar homology-dependent silencing mechanisms have been documented in several diverse systems, such as plant, fungal, protozoan, planarian, and insect systems. To expand our understanding of RNAi and its possible relationship to other post-transcriptional silencing mechanisms, we are following the fate of the dsRNA trigger molecule during RNA interference. Two intriguing apects of RNAi are the requirement for both sense and anti-sense strands in the trigger and the ability of a double-stranded trigger to function at very low concentrations. Our data indicate that one role of the incoming sense strand is to provide biological stability for the complementary strand. Evidence from plants and Drosophila suggests that the trigger molecule may be cleaved into 23-25 nucleotide fragments during post-transcriptional gene silencing. Through the development of an in vivo assay which allows us to trace the fate of the trigger molecule, we have begun to address whether the dsRNA molecule undergoes similar processing during RNAi. By pursuing the characterization of the fate of the trigger molecule, we hope to acquire some insight into the mechanism of RNA interference.
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[
Geroscience,
2023]
Targeting aging is the future of twenty-first century preventative medicine. Small molecule interventions that promote healthy longevity are known, but few are well-developed and discovery of novel, robust interventions has stagnated. To accelerate longevity intervention discovery and development, high-throughput systems are needed that can perform unbiased drug screening and directly measure lifespan and healthspan metrics in whole animals. C. elegans is a powerful model system for this type of drug discovery. Combined with automated data capture and analysis technologies, truly high-throughput longevity drug discovery is possible. In this perspective, we propose the "million-molecule challenge", an effort to quantitatively assess 1,000,000 interventions for longevity within five years. The WormBot-AI, our best-in-class robotics and AI data analysis platform, provides a tool to achieve the million-molecule challenge for pennies per animal tested.
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[
Nat Methods,
2019]
Single-molecule localization microscopy (SMLM), while well established for cultured cells, is not yet fully compatible with tissue-scale samples. We introduce single-molecule oblique-plane microscopy (obSTORM), which by directly imaging oblique sections of samples with oblique light-sheet illumination offers a deep and volumetric SMLM platform that is convenient for standard tissue samples and small intact animals. We demonstrate super-resolution imaging at depths of up to 66m for cells, Caenorhabditis elegans gonads, Drosophila melanogaster larval brain, mouse retina and brain sections, and whole stickleback fish.