Quiescence Enhances Survival during Viral Infection in .

Infection causes reduced activity, anorexia, and sleep, which are components of the phylogenetically conserved but poorly understood sickness behavior. We developed a model to study quiescence during chronic infection, using infection with the Orsay virus. The Orsay virus infects intestinal cells yet strongly affects behavior, indicating gut-to-nervous system communication.

Structural neuroplasticity after sleep loss modifies behavior and requires neurexin and neuroligin.

Structural neuroplasticity (changes in the size, strength, number, and targets of synaptic connections) can be modified by sleep and sleep disruption. However, the causal relationships between genetic perturbations, sleep loss, neuroplasticity, and behavior remain unclear. The GABAergic DVB neuron undergoes structural plasticity in adult males in response to adolescent stress, which rewires synaptic connections, alters behavior, and is dependent on conserved autism-associated genes / and We find that four methods of sleep deprivation transiently induce DVB neurite extension in day 1 adults and increase the time to spicule protraction, which is the functional and behavioral output of the DVB neuron.

A robotic system for automated genetic manipulation and analysis of .

The nematode is one of the most widely studied organisms in biology due to its small size, rapid life cycle, and manipulable genetics. Research with depends on labor-intensive and time-consuming manual procedures, imposing a major bottleneck for many studies, especially for those involving large numbers of animals. Here, we describe a general-purpose tool, WormPicker, a robotic system capable of performing complex genetic manipulations and other tasks by imaging, phenotyping, and transferring on standard agar media.

Beyond the symptom: the biology of fatigue.

A workshop titled "Beyond the Symptom: The Biology of Fatigue" was held virtually September 27-28, 2021. It was jointly organized by the Sleep Research Society and the Neurobiology of Fatigue Working Group of the NIH Blueprint Neuroscience Research Program. For access to the presentations and video recordings, see: https://neuroscienceblueprint.

G protein-coupled receptor kinase-2 (GRK-2) controls exploration through neuropeptide signaling in Caenorhabditis elegans.

Animals alter their behavior in manners that depend on environmental conditions as well as their developmental and metabolic states. For example, C. elegans is quiescent during larval molts or during conditions of satiety.

Pharyngeal timing and particle transport defects in feeding mutants.

The nematode uses rhythmic muscle contractions (pumps) of the pharynx, a tubular feeding organ, to filter, transport, and crush food particles. A number of feeding mutants have been identified, including those with slow pharyngeal pumping rate, weak muscle contraction, defective muscle relaxation, and defective grinding of bacteria. Many aspects of these pharyngeal behavioral defects and how they affect pharyngeal function are not well understood.

Motivated displacement assay distinguishes ALA neuron mutants from RIS neuron mutants during recovery from heat stress in .

The interneurons ALA and RIS both regulate stress induced sleep in but their roles in awake animal movement has been reported to differ. We describe the development of a motivated mobility-based assay that distinguishes between animals mutant for ALA function and those mutant for RIS function.

Caenorhabditis elegans exhibits positive gravitaxis.

Background: Gravity plays an important role in most life forms on Earth. Yet, a complete molecular understanding of sensing and responding to gravity is lacking. While there are anatomical differences among animals, there is a remarkable conservation across phylogeny at the molecular level.

Sleep: AMPs Mediate Injury-Induced Lethargy.

Fatigue and sleepiness are widely observed but ill-understood responses to tissue injury. A new study in Caenorhabditis elegans illuminates how the innate immune system mediates injury-induced sleep, which may help in surviving the injury.

Dehydrated Stocks Are Resistant to Multiple Freeze-Thaw Cycles.

Ultracold preservation is widely used for storage of genetic stocks of Current cryopreservation protocols are vulnerable to refrigeration failures, which can result in the loss of stock viability due to damage during re-freezing. Here we present a method for preserving worms in a dehydrated and frozen form that retains viability after multiple freeze-thaw cycles. After dehydration in the presence of trehalose or glycerol, stocks can be frozen and thawed multiple times while maintaining viability.

Behavioral States.

' behavioral states, like those of other animals, are shaped by its immediate environment, its past experiences, and by internal factors. We here review the literature on behavioral states and their regulation. We discuss dwelling and roaming, local and global search, mate finding, sleep, and the interaction between internal metabolic states and behavior.

RPamide neuropeptides NLP-22 and NLP-2 act through GnRH-like receptors to promote sleep and wakefulness in C. elegans.

Sleep and wakefulness are fundamental behavioral states of which the underlying molecular principles are becoming slowly elucidated. Transitions between these states require the coordination of multiple neurochemical and modulatory systems. In Caenorhabditis elegans sleep occurs during a larval transition stage called lethargus and is induced by somnogenic neuropeptides.

Teething during sleep: Ultrastructural analysis of pharyngeal muscle and cuticular grinder during the molt in Caenorhabditis elegans.

Complex extracellular structures exist throughout phylogeny, but the dynamics of their formation and dissolution are often opaque. One example is the pharyngeal grinder of the nematode Caenorhabditis elegans, an extracellular structure that ruptures bacteria during feeding. During each larval transition stage, called lethargus, the grinder is replaced with one of a larger size.

A salt-induced kinase is required for the metabolic regulation of sleep.

Many lines of evidence point to links between sleep regulation and energy homeostasis, but mechanisms underlying these connections are unknown. During Caenorhabditis elegans sleep, energetic stores are allocated to nonneural tasks with a resultant drop in the overall fat stores and energy charge. Mutants lacking KIN-29, the C.

A quiescent state following mild sensory arousal in Caenorhabditis elegans is potentiated by stress.

An animal's behavioral and physiological response to stressors includes changes to its responses to stimuli. How such changes occur is not well understood. Here we describe a Caenorhabditis elegans quiescent behavior, post-response quiescence (PRQ), which is modulated by the C.

Quantitative imaging of sleep behavior in Caenorhabditis elegans and larval Drosophila melanogaster.

Sleep is nearly universal among animals, yet remains poorly understood. Recent work has leveraged simple model organisms, such as Caenorhabditis elegans and Drosophila melanogaster larvae, to investigate the genetic and neural bases of sleep. However, manual methods of recording sleep behavior in these systems are labor intensive and low in throughput.

Exploring phylogeny to find the function of sleep.

During sleep, animals do not eat, reproduce or forage. Sleeping animals are vulnerable to predation. Yet, the persistence of sleep despite evolutionary pressures, and the deleterious effects of sleep deprivation, indicate that sleep serves a function or functions that cannot easily be bypassed.

A sleep state in larvae required for neural stem cell proliferation.

Sleep during development is involved in refining brain circuitry, but a role for sleep in the earliest periods of nervous system elaboration, when neurons are first being born, has not been explored. Here we identify a sleep state in larvae that coincides with a major wave of neurogenesis. Mechanisms controlling larval sleep are partially distinct from adult sleep: octopamine, the analog of mammalian norepinephrine, is the major arousal neuromodulator in larvae, but dopamine is not required.

Factors associated with fatigue in prostate cancer (PC) patients undergoing external beam radiation therapy (EBRT).

Purpose: Fatigue is a common adverse effect among cancer patients undergoing external beam radiation therapy (EBRT), yet the underlying disease- and treatment-related factors influencing its development are poorly understood. We hypothesized that clinical, demographic, and treatment-related factors differentially affect fatigue and aimed to better characterize variables related to fatigue development in prostate cancer (PC) patients during EBRT.

Methods And Materials: We identified a cohort of 681 patients with nonmetastatic PC undergoing a 6- to 9-week EBRT course.

Stress-Induced Sleep After Exposure to Ultraviolet Light Is Promoted by p53 in .

Stress-induced sleep (SIS) in is important for restoration of cellular homeostasis and is a useful model to study the function and regulation of sleep. SIS is triggered when epidermal growth factor (EGF) activates the ALA neuron, which then releases neuropeptides to promote sleep. To further understand this behavior, we established a new model of SIS using irradiation by ultraviolet C (UVC) light.

Longitudinal imaging of in a microfabricated device reveals variation in behavioral decline during aging.

The roundworm is a mainstay of aging research due to its short lifespan and easily manipulable genetics. Current, widely used methods for long-term measurement of are limited by low throughput and the difficulty of performing longitudinal monitoring of aging phenotypes. Here we describe the WorMotel, a microfabricated device for long-term cultivation and automated longitudinal imaging of large numbers of confined to individual wells.

Quantitative Assessment of Fat Levels in Using Dark Field Microscopy.

The roundworm is widely used as a model for studying conserved pathways for fat storage, aging, and metabolism. The most broadly used methods for imaging fat in require fixing and staining the animal. Here, we show that dark field images acquired through an ordinary light microscope can be used to estimate fat levels in worms.