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.

Neuromodulators: an essential part of survival.

The coordination between the animal's external environment and internal state requires constant modulation by chemicals known as neuromodulators. Neuromodulators, such as biogenic amines, neuropeptides and cytokines, promote organismal homeostasis. Over the past several decades, has grown into a powerful model organism that allows the elucidation of the mechanisms of action of neuromodulators that are conserved across species.

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.

NADPH oxidase-mediated redox signaling promotes oxidative stress resistance and longevity through in .

Transient increases in mitochondrially-derived reactive oxygen species (ROS) activate an adaptive stress response to promote longevity. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases produce ROS locally in response to various stimuli, and thereby regulate many cellular processes, but their role in aging remains unexplored. Here, we identified the orthologue of mammalian mediator of ErbB2-driven cell motility, MEMO-1, as a protein that inhibits BLI-3/NADPH oxidase.

Food-derived sensory cues modulate longevity via distinct neuroendocrine insulin-like peptides.

Environmental fluctuations influence organismal aging by affecting various regulatory systems. One such system involves sensory neurons, which affect life span in many species. However, how sensory neurons coordinate organismal aging in response to changes in environmental signals remains elusive.

Sensory systems: their impact on C. elegans survival.

An animal's survival strongly depends on a nervous system that can rapidly process and integrate the changing quality of its environment and promote the most appropriate physiological responses. This is amply demonstrated in the nematode worm Caenorhabditis elegans, where its sensory system has been shown to impact multiple physiological traits that range from behavior and developmental plasticity to longevity. Because of the accessibility of its nervous system and the number of tools available to study and manipulate its neural circuitry, C.

Positive and negative gustatory inputs affect Drosophila lifespan partly in parallel to dFOXO signaling.

In Caenorhabditis elegans, a subset of gustatory neurons, as well as olfactory neurons, shortens lifespan, whereas a different subset of gustatory neurons lengthens it. Recently, the lifespan-shortening effect of olfactory neurons has been reported to be conserved in Drosophila. Here we show that the Drosophila gustatory system also affects lifespan in a bidirectional manner.

Water sensor ppk28 modulates Drosophila lifespan and physiology through AKH signaling.

Sensory perception modulates lifespan across taxa, presumably due to alterations in physiological homeostasis after central nervous system integration. The coordinating circuitry of this control, however, remains unknown. Here, we used the Drosophila melanogaster gustatory system to dissect one component of sensory regulation of aging.

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.

Neuronal inputs and outputs of aging and longevity.

An animal's survival strongly depends on its ability to maintain homeostasis in response to the changing quality of its external and internal environment. This is achieved through intracellular and intercellular communication within and among different tissues. One of the organ systems that plays a major role in this communication and the maintenance of homeostasis is the nervous system.

Two insulin-like peptides antagonistically regulate aversive olfactory learning in C. elegans.

The insulin/insulin-like peptides (ILPs) regulate key events in physiology, including neural plasticity. However, the cellular and circuit mechanisms whereby ILPs regulate learning remain largely unknown. Here, we characterize two ILPs that play antagonistic roles in aversive olfactory learning of C.

Specific insulin-like peptides encode sensory information to regulate distinct developmental processes.

An insulin-like signaling pathway mediates the environmental influence on the switch between the C. elegans developmental programs of reproductive growth versus dauer arrest. However, the specific role of endogenous insulin-like peptide (ILP) ligands in mediating the switch between these programs remains unknown.

The thioredoxin TRX-1 modulates the function of the insulin-like neuropeptide DAF-28 during dauer formation in Caenorhabditis elegans.

Thioredoxins comprise a conserved family of redox regulators involved in many biological processes, including stress resistance and aging. We report that the C. elegans thioredoxin TRX-1 acts in ASJ head sensory neurons as a novel modulator of the insulin-like neuropeptide DAF-28 during dauer formation.

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.

A neuromedin U receptor acts with the sensory system to modulate food type-dependent effects on C. elegans lifespan.

The type of food source has previously been shown to be as important as the level of food intake in influencing lifespan. Here we report that different Escherichia coli food sources alter Caenorhabditis elegans lifespan. These effects are modulated by different subsets of sensory neurons, which act with nmur-1, a homolog of mammalian neuromedin U receptors.

The toposome, essential for sea urchin cell adhesion and development, is a modified iron-less calcium-binding transferrin.

We describe the structure and function of the toposome, a modified calcium-binding, iron-less transferrin, the first member of a new class of cell adhesion proteins. In addition to the amino acid sequence of the precursor, we determined by Edman degradation the N-terminal amino acid sequences of the mature hexameric glycoprotein present in the egg as well as that of its derived proteolytically modified fragments necessary for development beyond the blastula stage. The approximate C-termini of the fragments were determined by a combination of mass spectrometry and migration in reducing gels before and after deglycosylation.

Regulation of C. elegans longevity by specific gustatory and olfactory neurons.

The life span of C. elegans is extended by mutations that inhibit the function of sensory neurons. In this study, we show that specific subsets of sensory neurons influence longevity.