Characterization of muscle growth and sarcomere branching in the striated musculature of .

Striated muscles are essential for locomotion and survival. Their function and structure are highly conserved across taxa. Muscles are highly plastic.

Muscular expression of differentially contributes to swimming and crawling production in the nematode .

Mechanosensitive PIEZO ion channels are evolutionarily conserved proteins that are widely expressed in neuronal and muscular tissues. This study explores the role of the mechanoreceptor PEZO-1 in the body wall muscles of , focusing on its influence on two locomotor behaviors, swimming and crawling. Using confocal imaging, we reveal that PEZO-1 localizes to the sarcolemma and plays a crucial role in modulating calcium dynamics that are important for muscle contraction.

The mechanoreceptor is required for normal crawling locomotion in the nematode .

The discovery in 2010 of the PIEZO family of mechanoreceptors revolutionized our understanding of the role of proprioceptive feedback in mammalian physiology. Much remains to be elucidated. This study looks at the role this receptor plays in normal locomotion.

Thermal acclimation and habitat-dependent differences in temperature robustness of a crustacean motor circuit.

Introduction: At the cellular level, acute temperature changes alter ionic conductances, ion channel kinetics, and the activity of entire neuronal circuits. This can result in severe consequences for neural function, animal behavior and survival. In poikilothermic animals, and particularly in aquatic species whose core temperature equals the surrounding water temperature, neurons experience rather rapid and wide-ranging temperature fluctuations.

Quantitative description of neuronal calcium dynamics in C. elegans' thermoreception.

The dynamical mechanisms underlying thermoreception in the nematode C. elegans are studied with a mathematical model for the amphid finger-like ciliated (AFD) neurons. The equations, equipped with Arrhenius temperature factors, account for the worm's thermotaxis when seeking environments at its cultivation temperature, and for the AFD's calcium dynamics when exposed to both linearly ramping and oscillatory temperature stimuli.

Combining Old and New Tricks: The Study of Genes, Neurons, and Behavior in Crayfish.

For over a century the nervous system of decapod crustaceans has been a workhorse for the neurobiology community. Many fundamental discoveries including the identification of electrical and inhibitory synapses, lateral and pre-synaptic inhibition, and the Na/K-pump were made using lobsters, crabs, or crayfish. Key among many advantages of crustaceans for neurobiological research is the unique access to large, accessible, and identifiable neurons, and the many distinct and complex behaviors that can be observed in lab settings.

Methods for Modulating and Measuring Neuromuscular Exertion in C. elegans.

The nematode C. elegans has been used widely to study the genetic and cellular basis of behavior. Yet the laboratory conditions under which it is typically studied offer only a narrow glimpse into the richness of natural behaviors this remarkable animal evolved over 500 million years of evolution.

The dynamic range of voltage-dependent gap junction signaling is maintained by -induced membrane potential depolarization.

Like their chemical counterparts, electrical synapses show complex dynamics such as rectification and voltage dependence that interact with other electrical processes in neurons. The consequences arising from these interactions for the electrical behavior of the synapse, and the dynamics they create, remain largely unexplored. Using a voltage-dependent electrical synapse between a descending modulatory projection neuron (MCN1) and a motor neuron (LG) in the crustacean stomatogastric ganglion, we find that the influence of the hyperpolarization-activated inward current () is critical to the function of the electrical synapse.

Distinct mechanoreceptor pezo-1 isoforms modulate food intake in the nematode Caenorhabditis elegans.

Two PIEZO mechanosensitive cation channels, PIEZO1 and PIEZO2, have been identified in mammals, where they are involved in numerous sensory processes. While structurally similar, PIEZO channels are expressed in distinct tissues and exhibit unique properties. How different PIEZOs transduce force, how their transduction mechanism varies, and how their unique properties match the functional needs of the tissues they are expressed in remain all-important unanswered questions.

Neuronal membrane glycoprotein (nmgp-1) gene deficiency affects chemosensation-related behaviors, dauer exit and egg-laying in Caenorhabditis elegans.

The nervous system monitors the environment to maintain homeostasis, which can be affected by stressful conditions. Using mammalian models of chronic stress, we previously observed altered brain levels of GPM6A, a protein involved in neuronal morphology. However, GPM6A's role in systemic stress responses remains unresolved.

Physiologists turned Geneticists: Identifying transcripts and genes for neuronal function in the Marbled Crayfish, .

The number of undergraduate researchers interested in pursuing neurophysiological research exceeds the research laboratory positions and hands-on course experiences available because these types of experiments often require extensive experience or expensive equipment. In contrast, genetic and molecular tools can more easily incorporate undergraduates with less time or training. With the explosion of newly sequenced genomes and transcriptomes, there is a large pool of untapped molecular and genetic information which would greatly inform neurophysiological processes.

Affordable tracking system for classroom use.

For decades the nematode has served as an outstanding research organism owing to its unsurpassed experimental amenability. This advantage has also made this tiny worm an attractive vehicle for science instruction across higher learning institutions. However, the prohibitive cost associated with the automated behavioral assessment of these animals remains an obstacle preventing their full adoption in undergraduate and high school settings.

Factors that influence magnetic orientation in Caenorhabditis elegans.

Magnetoreceptive animals orient to the earth's magnetic field at angles that change depending on temporal, spatial, and environmental factors such as season, climate, and position within the geomagnetic field. How magnetic migratory preference changes in response to internal or external stimuli is not understood. We previously found that Caenorhabditis elegans orients to magnetic fields favoring migrations in one of two opposite directions.

Physical exertion exacerbates decline in the musculature of an animal model of Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a genetic disorder caused by loss of the protein dystrophin. In humans, DMD has early onset, causes developmental delays, muscle necrosis, loss of ambulation, and death. Current animal models have been challenged by their inability to model the early onset and severity of the disease.

Response to comment on "Magnetosensitive neurons mediate geomagnetic orientation in .

Many animals can orient using the earth's magnetic field. In a recent study, we performed three distinct behavioral assays providing evidence that the nematode orients to earth-strength magnetic fields (Vidal-Gadea et al., 2015).

Magnetic orientation in C. elegans relies on the integrity of the villi of the AFD magnetosensory neurons.

The magnetic field of the earth provides many organisms with sufficient information to successfully navigate through their environments. While evidence suggests the widespread use of this sensory modality across many taxa, it remains an understudied sensory modality. We have recently showed that the nematode C.

Method for the assessment of neuromuscular integrity and burrowing choice in vermiform animals.

Background: The study of locomotion in vermiform animals has largely been restricted to animals crawling on agar surfaces. While this has been fruitful in the study of neuronal basis of disease and behavior, the reduced physical challenge posed by these environments has prevented these organisms from being equally successful in the study of neuromuscular diseases. Our burrowing assay allowed us to study the effects of muscular exertion on locomotion and muscle degeneration during disease (Beron et al.

Magnetosensitive neurons mediate geomagnetic orientation in Caenorhabditis elegans.

Many organisms spanning from bacteria to mammals orient to the earth's magnetic field. For a few animals, central neurons responsive to earth-strength magnetic fields have been identified; however, magnetosensory neurons have yet to be identified in any animal. We show that the nematode Caenorhabditis elegans orients to the earth's magnetic field during vertical burrowing migrations.

The burrowing behavior of the nematode Caenorhabditis elegans: a new assay for the study of neuromuscular disorders.

The nematode Caenorhabditis elegans has been a powerful model system for the study of key muscle genes relevant to human neuromuscular function and disorders. The behavioral robustness of C. elegans, however, has hindered its use in the study of certain neuromuscular disorders because many worm models of human disease show only subtle phenotypes while crawling.

Humidity sensation requires both mechanosensory and thermosensory pathways in Caenorhabditis elegans.

All terrestrial animals must find a proper level of moisture to ensure their health and survival. The cellular-molecular basis for sensing humidity is unknown in most animals, however. We used the model nematode Caenorhabditis elegans to uncover a mechanism for sensing humidity.

The evolutionary transition to sideways-walking gaits in brachyurans was accompanied by a reduction in the number of motor neurons innervating proximal leg musculature.

The forwards-walking portly crab, Libinia emarginata is an ancient brachyuran. Its phylogenetic position and behavioral repertoire make it an excellent candidate to reveal the adaptations, which were required for brachyuran crabs to complete their transition to sideways-walking from their forwards-walking ancestors. Previously we showed that in common with other forwards-walking (but distantly related) crustaceans, L.

Conserved role of dopamine in the modulation of behavior.

Dopamine is an ancient signaling molecule. It is responsible for maintaining the adaptability of behavioral outputs and is found across taxa. The following is a summary of the role of dopamine and the mechanisms of its function and dysfunction.

Coordination of behavioral hierarchies during environmental transitions in .

For animals inhabiting multiple environments, the ability to select appropriate behaviors is crucial as their adaptability is often context dependent. uses distinct gaits to move on land and in water. Gait transitions can potentially coordinate behaviors associated with distinct environments.

Caenorhabditis elegans selects distinct crawling and swimming gaits via dopamine and serotonin.

Many animals, including humans, select alternate forms of motion (gaits) to move efficiently in different environments. However, it is unclear whether primitive animals, such as nematodes, also use this strategy. We used a multifaceted approach to study how the nematode Caenorhabditis elegans freely moves into and out of water.

Coding characteristics of spiking local interneurons during imposed limb movements in the locust.

The performance of adaptive behavior relies on continuous sensory feedback to produce relevant modifications to central motor patterns. The femoral chordotonal organ (FeCO) of the legs of the desert locust monitors the movements of the tibia about the femoro-tibial joint. A ventral midline population of spiking local interneurons in the metathoracic ganglia integrates inputs from the FeCO.