Specific sensory neurons and insulin-like peptides modulate food type-dependent oogenesis and fertilization in .

An animal's responses to environmental cues are critical for its reproductive program. Thus, a mechanism that allows the animal to sense and adjust to its environment should make for a more efficient reproductive physiology. Here, we demonstrate that in specific sensory neurons influence onset of oogenesis through insulin signaling in response to food-derived cues.

3D Structure From 2D Microscopy Images Using Deep Learning.

Understanding the structure of a protein complex is crucial in determining its function. However, retrieving accurate 3D structures from microscopy images is highly challenging, particularly as many imaging modalities are two-dimensional. Recent advances in Artificial Intelligence have been applied to this problem, primarily using voxel based approaches to analyse sets of electron microscopy images.

A Multicellular Network Mechanism for Temperature-Robust Food Sensing.

Responsiveness to external cues is a hallmark of biological systems. In complex environments, it is crucial for organisms to remain responsive to specific inputs even as other internal or external factors fluctuate. Here, we show how the nematode Caenorhabditis elegans can discriminate between different food levels to modulate its lifespan despite temperature perturbations.

Pheromones Modulate Learning by Regulating the Balanced Signals of Two Insulin-like Peptides.

Social environment modulates learning through unknown mechanisms. Here, we report that a pheromone mixture that signals overcrowding inhibits C. elegans from learning to avoid pathogenic bacteria.

Genetic dissection of neuropeptide cell biology at high and low activity in a defined sensory neuron.

Neuropeptides are ubiquitous modulators of behavior and physiology. They are packaged in specialized secretory organelles called dense core vesicles (DCVs) that are released upon neural stimulation. Unlike synaptic vesicles, which can be recycled and refilled close to release sites, DCVs must be replenished by de novo synthesis in the cell body.

Quantification of Information Encoded by Gene Expression Levels During Lifespan Modulation Under Broad-range Dietary Restriction in C. elegans.

Sensory systems allow animals to detect, process, and respond to their environment. Food abundance is an environmental cue that has profound effects on animal physiology and behavior. Recently, we showed that modulation of longevity in the nematode Caenorhabditis elegans by food abundance is more complex than previously recognized.

Genetic control of encoding strategy in a food-sensing neural circuit.

Neuroendocrine circuits encode environmental information via changes in gene expression and other biochemical activities to regulate physiological responses. Previously, we showed that TGFβ and tryptophan hydroxylase expression in specific neurons encode food abundance to modulate lifespan in , and uncovered cross- and self-regulation among these genes (Entchev et al., 2015).

A gene-expression-based neural code for food abundance that modulates lifespan.

How the nervous system internally represents environmental food availability is poorly understood. Here, we show that quantitative information about food abundance is encoded by combinatorial neuron-specific gene-expression of conserved TGFβ and serotonin pathway components in Caenorhabditis elegans. Crosstalk and auto-regulation between these pathways alters the shape, dynamic range, and population variance of the gene-expression responses of daf-7 (TGFβ) and tph-1 (tryptophan hydroxylase) to food availability.

Automated Processing of Imaging Data through Multi-tiered Classification of Biological Structures Illustrated Using Caenorhabditis elegans.

Quantitative imaging has become a vital technique in biological discovery and clinical diagnostics; a plethora of tools have recently been developed to enable new and accelerated forms of biological investigation. Increasingly, the capacity for high-throughput experimentation provided by new imaging modalities, contrast techniques, microscopy tools, microfluidics and computer controlled systems shifts the experimental bottleneck from the level of physical manipulation and raw data collection to automated recognition and data processing. Yet, despite their broad importance, image analysis solutions to address these needs have been narrowly tailored.

An insulin-to-insulin regulatory network orchestrates phenotypic specificity in development and physiology.

Insulin-like peptides (ILPs) play highly conserved roles in development and physiology. Most animal genomes encode multiple ILPs. Here we identify mechanisms for how the forty Caenorhabditis elegans ILPs coordinate diverse processes, including development, reproduction, longevity and several specific stress responses.

Selecting synaptic partners: GRASPing the role of UNC-6/netrin.

Forming synaptic connections of the appropriate strength between specific neurons is crucial for constructing neural circuits to control behavior. A recent paper in Neural Development describes the use of a synapse-specific label in Caenorhabditis elegans to implicate local UNC-6/netrin signaling in this developmental process. Thus, as well as their well known roles in cell migration and axon guidance, UNC-6/netrin signals distinguish an appropriate synaptic partner from other potential targets.

Sensory influence on homeostasis and lifespan: molecules and circuits.

The animal's ability to maintain homeostasis in response to different environments can influence its survival. This chapter will discuss the mechanisms by which environmental cues act through sensory pathways to influence hormone secretion and homeostasis. Interestingly, recent studies also show that there is a sensory influence on lifespan that requires the modulation of hormonal signaling activities.

Profiling synaptic proteins identifies regulators of insulin secretion and lifespan.

Cells are organized into distinct compartments to perform specific tasks with spatial precision. In neurons, presynaptic specializations are biochemically complex subcellular structures dedicated to neurotransmitter secretion. Activity-dependent changes in the abundance of presynaptic proteins are thought to endow synapses with different functional states; however, relatively little is known about the rules that govern changes in the composition of presynaptic terminals.

An RNAi screen identifies genes that regulate GABA synapses.

GABA synapses play a critical role in many aspects of circuit development and function. For example, conditions that perturb GABA transmission have been implicated in epilepsy. To identify genes that regulate GABA transmission, we performed an RNAi screen for genes whose inactivation increases the activity of C.

Systematic analysis of genes required for synapse structure and function.

Chemical synapses are complex structures that mediate rapid intercellular signalling in the nervous system. Proteomic studies suggest that several hundred proteins will be found at synaptic specializations. Here we describe a systematic screen to identify genes required for the function or development of Caenorhabditis elegans neuromuscular junctions.

Identification of genes that regulate a left-right asymmetric neuronal migration in Caenorhabditis elegans.

In C. elegans, cells of the QL and QR neuroblast lineages migrate with left-right asymmetry; QL and its descendants migrate posteriorly whereas QR and its descendants migrate anteriorly. One key step in generating this asymmetry is the expression of the Hox gene mab-5 in the QL descendants but not in the QR descendants.