Yehuda Ben-Shahar | Washington University in St. Louis (original) (raw)

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Papers by Yehuda Ben-Shahar

Proceedings of the National Academy of Sciences of the United States of America, Jan 17, 2014

When not satiated prior to training, there were no dierences between foragers and nurse honey bee... more When not satiated prior to training, there were no dierences between foragers and nurse honey bees in the acquisition of an appetitively based conditioned response in an olfactory associative learning assay, but when satiated foragers showed faster acquisition than did nurses. Satiation-related dierences between foragers and nurses were more a function of behavioral state than age, because satiated precocious foragers also showed faster acquisition rates than did satiated nurse bees, despite their similar ages. Tests of sucrose responsiveness and retention of conditioned responses indicate that the observed performance dierences between nurses and foragers were more likely due to dierential sensitivity of sensory and motor processes related to satiation rather than dierences in cognitive ability.

G3 (Bethesda, Md.), 2013

Degenerin/epithelial sodium channels (DEG/ENaC) represent a large family of animal-specific membr... more Degenerin/epithelial sodium channels (DEG/ENaC) represent a large family of animal-specific membrane proteins. Although the physiological functions of most family members are not known, some have been shown to act as nonvoltage gated, amiloride-sensitive sodium channels. The DEG/ENaC family is exceptionally large in genomes of Drosophila species relative to vertebrates and other insects. To elucidate the evolutionary history of the DEG/ENaC family in Drosophila, we took advantage of the genomic and genetic information available for 12 Drosophila species that represent all the major species groups in the Drosophila clade. We have identified 31 family members (termed pickpocket genes) in Drosophila melanogaster, which can be divided into six subfamilies, which are represented in all 12 species. Structure prediction analyses suggested that some subunits evolved unique structural features in the large extracellular domain, possibly supporting mechanosensory functions. This finding is fu...

Biology open, 2014

The response of individual animals to mating signals depends on the sexual identity of the indivi... more The response of individual animals to mating signals depends on the sexual identity of the individual and the genetics of the mating targets, which represent the mating social context (social environment). However, how social signals are sensed and integrated during mating decisions remains a mystery. One of the models for understanding mating behaviors in molecular and cellular terms is the male courtship ritual in the fruit fly (Drosophila melanogaster). We have recently shown that a subset of gustatory receptor neurons (GRNs) that are enriched in the male appendages and express the ion channel ppk23 play a major role in the initiation and maintenance of male courtship via the perception of cuticular contact pheromones, and are likely to represent the main chemosensory pathway that influences mating decisions by males. Here we show that genetic feminization of ppk23-expressing GRNs in male flies resulted in a significant increase in male-male sexual attraction without an apparent ...

eLife, 2014

Neurons regulate ionic fluxes across their plasma membrane to maintain their excitable properties... more Neurons regulate ionic fluxes across their plasma membrane to maintain their excitable properties under varying environmental conditions. However, the mechanisms that regulate ion channels abundance remain poorly understood. Here we show that pickpocket 29 (ppk29), a gene that encodes a Drosophila degenerin/epithelial sodium channel (DEG/ENaC), regulates neuronal excitability via a protein-independent mechanism. We demonstrate that the mRNA 3′UTR of ppk29 affects neuronal firing rates and associated heat-induced seizures by acting as a natural antisense transcript (NAT) that regulates the neuronal mRNA levels of seizure (sei), the Drosophila homolog of the human Ether-à-go-go Related Gene (hERG) potassium channel. We find that the regulatory impact of ppk29 mRNA on sei is independent of the sodium channel it encodes. Thus, our studies reveal a novel mRNA dependent mechanism for the regulation of neuronal excitability that is independent of protein-coding capacity.

Animal Cognition, 2000

We studied the association between honey bee (Apis mellifera) division of labor and performance o... more We studied the association between honey bee (Apis mellifera) division of labor and performance on an olfactory reversal-learning test. Manipulations of colony age structure and flight experience were used to test whether differences in performance are associated with age, current behavioral state, or flight experience. Nurse bees showed significantly faster rates of extinction to a learned odor than did foragers.

Trends in Ecology and Evolution, 2005

Frontiers in Behavioral Neuroscience, 2012

Manganese (Mn2+) is an essential transition metal involved in growth, development, cellular respi... more Manganese (Mn2+) is an essential transition metal involved in growth, development, cellular respiration and energy homeostasis, acting as a cofactor for various enzymes. Maintaining homeostatic balance of divalent metal ions like Mn2+ is critical for physiology. Mn2+ transporter proteins have been found to be involved in taste behavior in insects. Thus developing a proper understanding of the role of Mn2+ in modulating sensory systems (e.g., taste) will help in elucidating its role in modulating behavior. The fruit fly Drosophila melanogaster was used as a model to study the effect of Mn2+ on the nervous system. Preliminary results showed that flies raised from egg to adult in food that contains Mn2+ have higher levels of the biogenic amines Dopamine (DA) and Octopamine (OA) but not Serotonin (5-HT) in their brains, as compared to control flies. Since both DA and OA are known to be involved in regulating various behaviors, we hypothesized that the effects of disruptions in Mn2+ homeostasis on behavior are mediated by a direct impact on aminergic signaling in the insect brain. We followed up on these results by raising flies in different concentrations of Mn2+, followed by determination of brain amine levels, aminergic neuroanatomy, gene transcription, and behavioral outcomes. Evidence was found suggesting that Mn2+ may affect biogenic amine levels by impacting transcription levels of genes involved in biogenic amine synthesis pathways, and it was also found that Mn2+ treatment can affect gustatory behavior, whereas aminergic neuroanatomy remains unaffected on exposure to Mn2+ levels that change behavior and aminergic gene expression.

PLOS One, 2010

Degenerin/epithelial Na+ channels (DEG/ENaC) represent a diverse family of voltage-insensitive ca... more Degenerin/epithelial Na+ channels (DEG/ENaC) represent a diverse family of voltage-insensitive cation channels whose functions include Na+ transport across epithelia, mechanosensation, nociception, salt sensing, modification of neurotransmission, and detecting the neurotransmitter FMRFamide. We previously showed that the Drosophila melanogaster Deg/ENaC gene lounge lizard (llz) is co-transcribed in an operon-like locus with another gene of unknown function, CheB42a. Because operons often encode

Methods in Molecular Biology, 2013

Olfactory receptors (OR) represent one of the largest gene families in the human genome. In spite... more Olfactory receptors (OR) represent one of the largest gene families in the human genome. In spite of a signi fi cant progress in deciphering the physiological functions of olfactory receptors, how the majority of these G-protein-coupled receptors are activated is still mostly a mystery. Consequently, for the majority of OR genes there are currently no assigned physiological or behavioral functions. Deciphering ligand speci fi cities and physiological signi fi cance of human ORs is important for understanding how the human olfactory genome encodes odors, and how such odors drive human behavior in health and disease. Although OR genes were originally thought to be restricted to the olfactory epithelium, several recent studies indicated that some members of the OR family might be acting outside the canonical chemosensory system. In a recent study, we have shown that the human airway epithelial cells can also act as chemosensory cells by directly sensing the inhalation of noxious bitter compounds, which can lead to increased mucociliary clearance, and hence may serve as a protective mechanism against inhaled toxins and microorganisms. Whether the airway epithelium can detect chemicals via other sensory pathways has not been reported to date. As a step in this direction, we describe methods for studying the cellular and subcellular localization of olfactory receptor proteins and mRNAs in human airways in both primary in vitro cultures and tissue sections.

Advances in Genetics, 2011

Journal of Experimental Biology, 2004

is facilitated by dissecting it into simpler behavioral components. Using this approach, we prese... more is facilitated by dissecting it into simpler behavioral components. Using this approach, we present evidence implicating increased manganese transport by the malvolio (mvl) gene into brain cells as one factor that influences age-related division of labor in honey bee colonies. We studied mvl because manganese affects sucrose responsiveness in Drosophila melanogaster, and sucrose responsiveness is related to division of labor in honey bee colonies. Honey bee foragers are more responsive to sucrose in the laboratory than are younger nurse bees, and pollen foragers are more responsive to sucrose than nectar foragers. Levels of mvl mRNA in the brain and manganese in the head were higher in pollen foragers compared with nurses, with nectar foragers intermediate. Manganese treatment increased honey bee sucrose responsiveness and caused precocious foraging. Manganese levels showed a similar pattern to mvl mRNA but manganese treatment did not increase pollen foraging. These results suggest that, while there are molecular pathways common to sucrose responsiveness and division of labor, linkages between a complex behavior and some of its simpler behavioral components are not obligatory. Together with previous findings, these results support the idea that some feeding-related genes in Drosophila have been used in social evolution to regulate division of labor.

Journal of Experimental Biology, 2003