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Moore, R. S.

Publications and source records attributed to Moore, R. S..

15 recordsLinked to original sources

Gut-derived serine protease reduces sleep but extends lifespan

Sleep has historically been viewed through a brain-centric lens with little known about the contribution of the periphery. Through a targeted screen of secreted peptides from the fat body, gut, and body wall muscle in Drosophila, we identified CG11037, a trypsin-like serine endopeptidase secreted from midgut enterocytes, as a previously unrecognized regulator of sleep. Loss of CG11037 reduces daily sleep, as well as sleep following injury/infection, although recovery is enhanced suggesting reduced need for sleep during sickness. Proteomic analysis of flies with reduced CG11037 revealed altered oxidative stress response pathways including cytochrome P450-related proteins. Indeed, gut-specific knockdown of Cyp6a2 or Cyp28d1 phenocopies CG11037 sleep defects, and loss of CG11037 or P450 elevates reactive oxygen species (ROS) selectively in the gut without affecting brain ROS. Rescue of sleep by antioxidant treatment demonstrates that peripheral ROS accumulation drives the behavioral phenotype. Strikingly, despite physiological dysfunction and reduced sleep, CG11037 or Cytochrome P450 knockdown extends lifespan in a ROS-dependent manner, suggesting that stress adaptation of these knockdowns allows them to live longer. Together, these findings uncover a mechanism for the unexpected association of reduced sleep and extended lifespan.

genetics↗

Constant light impairs memory processing transgenerationally in D. melanogaster

Environmental perturbations can have profound effects on our physiology and behavior, but their long-lasting impact remains debatable. We discovered that changes in standard light-dark conditions, such as exposure to constant light or simulated chronic jetlag, causes loss of associative memory in appetitive and aversive conditioning paradigms in D. melanogaster, and this behavior persists through three generations despite transfer of progeny to a standard light-dark cycle. Impaired memory is transmitted through females and is independent of any changes in fitness, brain or mushroom body architecture, or sensing acuity. Mechanistically, effects of constant light on memory are mediated by increased PIWI/piRNA pathway expression in the germline and its H3K9me3 writing capabilities, acting through altered expression of the Dopamine-1-like Receptor 1 (Dop1R1) in the brain. These findings suggest that irregular exposure to light, such as nighttime light pollution, can have negative consequences across generations. HIGHLIGHTSO_LIConstant light impairs associative memory in Drosophila for three generations C_LIO_LIpiwi is required in the brain and germline for inheritance C_LIO_LIDopamine 1 Receptor 1 activity is dampened by constant light C_LI

neuroscience↗

Molecular Requirements for C. elegans Transgenerational Epigenetic Inheritance of Pathogen Avoidance

C. elegans major food source is bacteria, and worms are naturally attracted to many bacterial species, including pathogenic Pseudomonas; in fact, worms prefer PA14 as well as wild bacteria over the lab E. coli strain (OP50) standardly used in the laboratory setting. Many labs have shown that despite this natural attraction to PA14, prior exposure to PA14 causes the worms to instead avoid PA14. This behavioral switch can happen on a relatively fast time scale, even within the duration of the choice assay. Here we show that accurate assessment of the animals true first choice requires the use of a paralytic (azide) to trap the worms at their initial choice, and to prevent the switch from attraction to avoidance of PA14 within the assay period. We previously discovered that exposure of C. elegans to 25{degrees}C plate-grown PA14 at 20{degrees}C for 24hrs not only leads to these animals switching from attraction to avoidance of PA14, but also to their progeny avoiding PA14 in the naive state, and this avoidance persists through the F4 generation. Other types of PA14 training can also cause P0 and/or F1 avoidance, but do not induce transgenerational (F2 and beyond) inheritance. We also previously showed that the transgenerational (P0-F4) learned avoidance is mediated by P11, a small RNA produced by PA14. P11 is both necessary and sufficient for transgenerational epigenetic inheritance of avoidance behavior. P11 is highly expressed in our standard growth conditions (25{degrees}C on surfaces), but not in other conditions, suggesting that reported failure to observe F2-F4 avoidance is most likely due to the absence of P11 expression in PA14 in the experimenters growth conditions. Through mutant analyses, we have tested many genes - including germline regulators, small RNA uptake, RNA interference/processing, chromatin modifiers, and neuronal genes -for their involvement in transgenerational inheritance of learned pathogen avoidance, allowing us to better understand the molecular requirements for this process. We previously found that wild C. elegans strains also show TEI of learned pathogen avoidance, and that at least two other wild bacteria, P. vranovensis and P. fluorescens 15, induce this transgenerational avoidance. The avoidance induced by each Pseudomonas species functions through a specific, distinct small RNA (Pv1 in P. vranovensis and Pfs1 in P. fluorescens 15, respectively) that either directly or indirectly reduce the levels of the gene maco-1, which in turn regulates daf-7 expression in the ASI neuron and subsequent avoidance behavior. The conservation of multiple components of this small RNA TEI mechanism across C. elegans strains and in multiple Pseudomonas species suggests that this transgenerational learned avoidance behavior is likely to be functional and physiologically important in wild conditions.

genetics↗

Absence of Evidence is Not Evidence of Absence: The many flaws in the case against transgenerational epigenetic inheritance of pathogen avoidance in C. elegans

After examining the data and methods presented in Gainey, et al., bioRxiv, 20241 we conclude that the authors did not use an experimental paradigm that would have allowed them to replicate our results on transgenerational epigenetic inheritance (TEI) of learned avoidance that we regularly observe2-5. That is, we agree with the authors that their experiments show no evidence of TEI. However, there are substantial differences in their execution of every step of the work that also make it impossible for the authors to claim that they are replicating our experiments or protocols. Based on these differences, we do not believe there is an issue of "robustness" and "reliability" in our TEI findings, but rather that Hunter and colleagues have in fact not tested the central condition of TEI - that is, small RNA production by bacteria and subsequent uptake by C. elegans - nor have they carried out proper behavioral and imaging assays to assess this behavior. Our subsequent work shows that indeed this example of transgenerational epigenetic inheritance is not just observed in laboratory settings with PA14, but is also induced by wild strains of Pseudomonas, exhibiting its robustness. Just as we offered advice and training to Hunter and colleagues, we are happy to advise anyone who wishes to learn this assay. We have now performed the experiments in the absence of azide, a deviation from our protocol that Hunter and colleagues deliberately made, and found that this omission may account for most if not all of the differences from our results. It is disingenuous for the authors to have presented their work as if they have used our protocol, given the fact that they chose to not use the same conditions for the most basic assay used in the work, the chemotaxis assay, which would have been necessary to replicate in order to reproduce our work. Therefore, Gainey et al.s claims that our protocol or results are "irreproducible" are not supported by their evidence.

genetics↗

Pseudomonas fluorescens 15 small RNA Pfs1 mediates transgenerational epigenetic inheritance of pathogen avoidance in C. elegans through the Ephrin receptor VAB-1

C. elegans are exposed to a variety of pathogenic and non-pathogenic bacteria species in their natural environment. Correspondingly, C. elegans has evolved an ability to discern between nutritive and infectious bacterial food sources. Here we show that C. elegans can learn to avoid the pathogenic bacteria Pseudomonas fluorescens 15 (PF15), and that this learned avoidance behavior is passed on to progeny for four generations, as we previously demonstrated for Pseudomonas aeruginosa (PA14) and Pseudomonas vranovensis, using similar mechanisms, including the involvement of both the TGF-{beta} ligand DAF-7 and Cer1 retrotransposon-encoded virus-like particles. PF15 small RNAs are both necessary and sufficient to induce this transgenerational avoidance behavior. Unlike PA14 or P. vranovensis, PF15 does not use P11, Pv1, or a small RNA with maco-1 homology for this avoidance; instead, an unrelated PF15 small RNA, Pfs1, that targets the C. elegans vab-1 Ephrin receptor gene is necessary and sufficient for learned avoidance, suggesting the evolution of yet another bacterial sRNA/C. elegans gene target pair involved in transgenerational inheritance of pathogen avoidance. As VAB-2 Ephrin receptor ligand and MACO-1 knockdown also induce PF15 avoidance, we have begun to understand the genetic pathway involved in small RNA targeted pathogenic avoidance. Moreover, these data show that axon guidance pathway genes (VAB-1 and VAB-2) have previously unknown adult roles in regulating neuronal function. C. elegans may have evolved multiple bacterial specificity-encoded small RNA-dependent mechanisms to avoid different pathogenic bacteria species, thereby providing progeny with a survival advantage in a dynamic environment.

genetics↗

Adult Single-nucleus Neuronal Transcriptomes of Insulin Signaling Mutants Reveal Regulators of Behavior and Learning

The insulin/insulin-like signaling (IIS) pathway regulates many of C. elegans adult functions, including learning and memory1. While whole-worm and tissue-specific transcriptomic analyses have identified IIS targets2,3, a higher-resolution single-cell approach is required to identify changes that confer neuron-specific improvements in the long-lived insulin receptor mutant, daf-2. To understand how behaviors that are controlled by a small number of neurons change in daf-2 mutants, we used the deep resolution of single-nucleus RNA sequencing to define each neuron types transcriptome in adult wild-type and daf-2 mutants. First, we found surprising differences between wild-type L4 larval neurons and young adult neurons in chemoreceptor expression, synaptic genes, and learning and memory genes. These Day 1 adult neuron transcriptomes allowed us to identify adult AWC-specific regulators of chemosensory function and to predict neuron-to-neuron peptide/receptor pairs. We then identified gene expression changes that correlate with daf-2s improved cognitive functions, particularly in the AWC sensory neuron that controls learning and associative memory4, and used behavioral assays to test their roles in cognitive function. Combining deep single-neuron transcriptomics, genetic manipulation, and behavioral analyses enabled us to identify genes that may function in a single adult neuron to control behavior, including conserved genes that function in learning and memory. One-Sentence SummarySingle-nucleus sequencing of adult wild-type and daf-2 C. elegans neurons reveals functionally relevant transcriptional changes, including regulators of chemosensation, learning, and memory.

neuroscience↗

A small RNA from a natural bacterial pathogen of C. elegans induces transgenerational inheritance of learned avoidance

Previously, we discovered that a small RNA from a clinical isolate of Pseudomonas aeruginosa, PA14, induces learned avoidance and its transgenerational inheritance in C. elegans. Pseudomonas aeruginosa is an important human pathogen, and there are other Pseudomonads in C. elegans natural habitat, but it is unclear whether C. elegans ever encounters PA14-like bacteria in the wild. Thus, it is not known if small RNAs from bacteria found in C. elegans natural habitat can also regulate host behavior and produce heritable behavioral effects. Here we found that a pathogenic Pseudomonas vranovensis strain isolated from the C. elegans microbiota, GRb0427, like PA14, regulates worm behavior: worms learn to avoid this pathogenic bacterium following exposure to GRb0427, and this learned avoidance is inherited for four generations. The learned response is entirely mediated by bacterially-produced small RNAs, which induce avoidance and transgenerational inheritance, providing further support that such mechanisms of learning and inheritance exist in the wild. Using bacterial small RNA sequencing, we identified Pv1, a small RNA from GRb0427, that matches the sequence of C. elegans maco-1. We find that Pv1 is both necessary and sufficient to induce learned avoidance of Grb0427. However, Pv1 also results in avoidance of a beneficial microbiome strain, P. mendocina; this potentially maladaptive response may favor reversal of the transgenerational memory after a few generations. Our findings suggest that bacterial small RNA-mediated regulation of host behavior and its transgenerational inheritance are functional in C. elegans natural environment, and that different bacterial small RNA-mediated regulation systems evolved independently but define shared molecular features of bacterial small RNAs that produce transgenerationally-inherited effects.

genetics↗

Sleep and memory consolidation are linked by RNA processing genes in the Drosophila mushroom body

Memory consolidation in Drosophila can be sleep-dependent or sleep-independent, depending on the availability of food. The anterior posterior (ap) alpha'/beta' ('/{beta}') neurons of the mushroom body (MB) are required for sleep-dependent memory consolidation in flies fed after training. These neurons are also involved in the increase of sleep after training, suggesting a coupling of sleep and memory. To better understand the mechanisms underlying sleep and memory consolidation initiation, we analyzed the transcriptome of ap '/{beta}' neurons one hour after appetitive memory conditioning. A small number of genes, enriched in RNA processing functions, were differentially expressed in flies fed after training relative to trained and starved flies or untrained flies. Knockdown of each of these differentially expressed genes in the ap '/{beta}' neurons revealed notable sleep phenotypes for Polr1F and Regnase-1, both of which decrease in expression after conditioning. Knockdown of Polr1F, a regulator of ribosome RNA transcription, in adult flies promotes sleep and increases pre-ribosome RNA expression as well as overall translation, supporting a function for Polr1F downregulation in sleep-dependent memory. Conversely, while constitutive knockdown of Regnase-1, an mRNA decay protein localized to the ribosome, reduces sleep, adult specific knockdown suggests that effects of Regnase-1 on sleep are developmental in nature. We further tested the role of each gene in memory consolidation. Knockdown of Polr1F does not affect memory, which may be expected from its downregulation during memory consolidation. Regnase-1 knockdown in ap '/{beta}' neurons impairs all memory, including short-term, implicating Regnase-1 in memory, but leaving open the question of why it is downregulated during sleep-dependent memory. Overall, our findings demonstrate that the expression of RNA processing genes is modulated during sleep-dependent memory and, in the case of Polr1F, this modulation likely contributes to increased sleep.

neuroscience↗

CeAid: A smartphone application for logging and plotting C. elegans assays

C. elegans is used as a model organism to study a wide range of topics in molecular and cellular biology. Conventional C. elegans assays often require a large sample size with frequent manipulations, rendering them labor-intensive. Automated high-throughput workflows may not be always the best solution to reduce benchwork labor, as they may introduce more complexity. Thus, most assays are carried out manually, where logging and digitizing experimental data can be as time-consuming as picking and scoring worms. Here we report the development of CeAid, C. elegans Application for inputting data, which significantly expedites the data entry process, utilizing swiping gestures and a voice recognition algorithm for logging data using a standard smartphone or Android device. This modular platform can also be adapted for a wide range of assays where recording data is laborious, even beyond worm research.

genetics↗

Horizontal and vertical transmission of transgenerational memories via the Cer1 transposon

Animals face both external and internal dangers: pathogens threaten from the environment, and unstable genomic elements threaten from within. Previously, we discovered that C. elegans protects itself from pathogens by "reading" bacterial small RNAs and using this information to both induce avoidance and transmit memories for several generations. Here we found that these memories can be transferred to naive animals via Cer1 retrotransposon-encoded capsids. Cer1 functions at the step of transmission of information from the germline to neurons, and is required for C. elegans learned avoidance ability and for mothers to pass this information on to progeny. The presence of the Cer1 retrotransposon in wild C. elegans strains correlates with the ability to learn and inherit small RNA-induced pathogen avoidance. Together, these results suggest that C. elegans has co-opted a potentially dangerous retrotransposon to instead protect itself and its progeny from a common pathogen through its inter-tissue signaling ability, hijacking this genomic element for its own adaptive immunity benefit.

genetics↗

C. elegans reads bacterial non-coding RNAs to learn pathogenic avoidance

C. elegans is exposed to many different bacteria in its environment, and must distinguish pathogenic from nutritious bacterial food sources. Here, we show that a single exposure to purified small RNAs isolated from pathogenic Pseudomonas aeruginosa (PA14) is sufficient to induce pathogen avoidance, both in the treated animals and in four subsequent generations of progeny. The RNA interference and piRNA pathways, the germline, and the ASI neuron are required for bacterial small RNA-induced avoidance behavior and transgenerational inheritance. A single non-coding RNA, P11, is both necessary and sufficient to convey learned avoidance of PA14, and its C. elegans target, maco-1, is required for avoidance. A natural microbiome Pseudomonas isolate, GRb0427, can induce avoidance via its small RNAs, and the wild C. elegans strain JU1580 responds similarly to bacterial sRNA. Our results suggest that this ncRNA-dependent mechanism evolved to survey the worms microbial environment, use this information to make appropriate behavioral decisions, and pass this information on to its progeny.

genetics↗

Cross-kingdom recognition of bacterial small RNAs induces transgenerational pathogenic avoidance

We recently discovered that C. elegans can pass on a learned avoidance of pathogenic Pseudomonas aeruginosa (PA14) to four generations of its progeny. This transgenerational inheritance is bacterial species-specific, but how C. elegans recognizes and distinguishes different bacteria and transmits this information to future generations is not apparent. Here we show that small RNAs purified from pathogenic PA14 are sufficient not only to induce avoidance of pathogens in mothers, but also to confer transgenerational inheritance of this species-specific behavior for four generations, all without direct contact with pathogenic bacteria. This behavior requires the small RNA transporters SID-1 and SID-2, RNA interference pathway components, the piRNA Piwi/Argonaute pathway, a functioning germline, and TGF-{beta} ligand daf-7 expression in the ASI sensory neuron. Our results suggest that C. elegans \"reads\" small RNAs expressed by pathogenic bacteria, and uses this information to induce an escape behavior that lasts for four additional generations. C. elegans may have evolved this trans-kingdom signaling system to avoid pathogens in abundant classes of bacteria in its environment and its microbiome.

genetics↗

A Drosophila metainflammation-blood tumor model links aspirin-triggered eicosanoid-like mediators to immune signaling

Accumulating data from epidemiologic studies are linking aspirins use to a decline in chronic and metabolic inflammation that underlies many human diseases including some cancers. Aspirin reduces cyclooxygenase-mediated pro-inflammatory prostaglandins and promotes the production of pro-resolution molecules. Aspirin also triggers the production of anti-inflammatory electrophilic mono-oxygenated lipid mediators implicated in human pathologies. With the goal of developing a model system for studying the mechanisms of aspirin in reducing inflammation, we investigated aspirins effects in fruit fly models of chronic inflammation. Ectopic Toll/NF-{kappa}B and JAK/STAT signaling in D. melanogaster results in an overproliferation of hematopoietic blood progenitors coupled with metabolic inflammation in adipocytes. We report that, like mammals, flies are sensitive to aspirin treatment and it modulates the Toll-NF-{kappa}B axis. Aspirin-treated mutants simultaneously experience reduction in metabolic inflammation, mitosis, ectopic immune signaling, and macrophage infiltration. Moreover, flies synthesize 13-HODE, and aspirin triggers 13-EFOX-L2 production in mutants. In such flies with ectopic immune signaling, providing 13-HODEs precursor linoleic acid or performing targeted knockdown of transcription factor STAT in inflammatory blood cells boosts 13-EFOX-L2 levels while decreasing metabolic inflammation. Thus, hematopoietic cells regulate metabolic inflammation in flies, and their effects can be reversed by pharmaceutical or dietary intervention, suggesting deep phylogenetic conservation in animals ability to resolve systemic inflammation and repair tissue damage. This model system brings the power of Drosophila genetics to bear on immuno-metabolic mechanisms that boost systemic health and healing, with the potential to identify new targets for the treatment of chronic diseases in humans.

immunology↗

C. elegans pathogenic learning confers multigenerational pathogen avoidance

The ability to pass on learned information to progeny could present an evolutionary advantage for many generations. While apparently evolutionarily conserved1-12, transgenerational epigenetic inheritance (TEI) is not well understood at the molecular or behavioral levels. Here we describe our discovery that C. elegans can pass on a learned pathogenic avoidance behavior to their progeny for several generations through epigenetic mechanisms. Although worms are initially attracted to the gram-negative bacteria P. aeruginosa (PA14)13, they can learn to avoid this pathogen13. We found that prolonged PA14 exposure results in transmission of avoidance behavior to progeny that have themselves never been exposed to PA14, and this behavior persists through the fourth generation. This form of transgenerational inheritance of bacterial avoidance is specific to pathogenic P. aeruginosa, requires physical contact and infection, and is distinct from CREB-dependent long-term associative memory and larval imprinting. The TGF-{beta} ligand daf-7, whose expression increases in the ASJ upon initial exposure to PA1414, is highly expressed in the ASI neurons of progeny of trained mothers until the fourth generation, correlating with transgenerational avoidance behavior. Mutants of histone modifiers and small RNA mediators display defects in naive PA14 attraction and aversive learning. By contrast, the germline-expressed PRG-1/Piwi homolog15 is specifically required for transgenerational inheritance of avoidance behavior. Our results demonstrate a novel and natural paradigm of TEI that may optimize progeny decisions and subsequent survival in the face of changing environmental conditions.

genetics↗

Investigation of lanthanide-dependent methylotrophy uncovers complementary roles for alcohol dehydrogenase enzymes

The discovery that methylotrophic bacteria can utilize lanthanides as catalysts for methanol metabolism has opened new areas of biology and biochemistry. Recent studies of lanthanide-dependent enzymes have focused on biochemical and kinetic properties or the regulation of encoding genes. Kinetic analysis of a pyrroloquinoline quinone methanol dehydrogenase, XoxF1 (MexAM1_1746), from the model methylotroph Methylobacterium extorquens AM1 confirms the use of different lanthanides as cofactors and formaldehyde as a product of methanol oxidation, showing that not all XoxF MDH produce formate as the only end product in vivo. The dephosphotetrahydromethanopterin pathway for formaldehyde oxidation is still required for lanthanide-methylotrophic growth, as a fae mutant does not grow with methanol in the presence of exogenous lanthanides. Increases of 15-22% in growth rate and 10-12.5% in growth yield are observed when M. extorquens AM1 is grown in the presence of lanthanides with methanol. RNA-sequencing transcriptomics indicates remodeling of methanol, formaldehyde and formate oxidation gene expression, and targeted metabolomics shows increased accumulation of intracellular formate and decreased pools of several assimilatory intermediates. Methanol sensitivity growth assays show that the lanthanide-dependent pyrroloquinoline quinone alcohol dehydrogenase ExaF (MexAM1_1139), but not XoxF1, can reduce formaldehyde toxicity when lanthanides are present, providing evidence of a role for ExaF during lanthanide-dependent methylotrophy. We conclude from these results that lanthanide-dependent methylotrophy is more efficient than calcium-dependent methylotrophy in M. extorquens AM1, and that this change is due, at least in part, to the lanthanide-dependent enzymes XoxF1 and ExaF.\n\nIMPORTANCELanthanides serve as cofactors for pyrroloquinoline quinone containing alcohol dehydrogenase enzymes in methylotrophic bacteria. The present study addresses a fundamental gap in our understanding of how lanthanides impact metabolism, including a detailed assessment of the metabolic modifications to accommodate enhanced efficiency during methylotrophy. Kinetic characterization of XoxF1 provides a detailed description of the impact of diverse lanthanides on catalytic function for a lanthanide-dependent methanol dehydrogenase. We further show that the lanthanide-dependent ethanol dehydrogenase ExaF can oxidize formaldehyde in vivo, revealing complementary roles for these enzymes. This study provides novel insight into the effects of lanthanides on bacterial metabolism, highlighting the implementation of multiple, redundant and complementary oxidation systems.

microbiology↗