Molecular mechanisms and physiological importance of circadian rhythms

Nature Reviews Molecular Cell Biology, Journal Year: 2019, Volume and Issue: 21(2), P. 67 - 84

Published: Nov. 25, 2019

Language: Английский

---

Circadian Rhythms and Sleep in Drosophila melanogaster

Genetics, Journal Year: 2017, Volume and Issue: 205(4), P. 1373 - 1397

Published: March 30, 2017

The advantages of the model organism Drosophila melanogaster, including low genetic redundancy, functional simplicity, and ability to conduct large-scale screens, have been essential for understanding molecular nature circadian (∼24 hr) rhythms, continue be valuable in discovering novel regulators rhythms sleep. In this review, we discuss current these interrelated biological processes wider implications research. Clock genes period timeless were first discovered screens developed 1970s. Feedback on their own transcription forms core clock, accurately timed expression, localization, post-transcriptional modification, function is thought critical maintaining cycle. Regulators, several phosphatases kinases, act different steps feedback loop ensure strong rhythms. Approximately 150 neurons fly brain that contain components clock together translate intracellular cycling into rhythmic behavior. We how groups serve functions allowing clocks entrain environmental cues, driving behavioral outputs at times day, flexible responses conditions. neuropeptide PDF provides an important signal synchronize neurons, although details accomplishes are still being explored. Secreted signals from also influence other tissues. SLEEP is, part, regulated by which ensures appropriate timing sleep, but amount quality sleep determined mechanisms a homeostatic balance between wake. Flies useful identifying large set genes, molecules, neuroanatomic loci regulating amount. Conserved aspects regulation flies mammals include wake-promoting roles catecholamine neurotransmitters involvement hypothalamus-like regions, regions implicated less clear parallels. Sleep subject factors such as food availability, stress, social environment. beginning understand identified molecules interact with each other, environment, regulate researchers can take advantage increasing mechanistic behaviors, learning memory, courtship, aggression, loss impacts behaviors. thus remain tool both discovery deep

Language: Английский

---

The Ionotropic Receptors IR21a and IR25a mediate cool sensing in Drosophila

eLife, Journal Year: 2016, Volume and Issue: 5

Published: April 28, 2016

Animals rely on highly sensitive thermoreceptors to seek out optimal temperatures, but the molecular mechanisms of thermosensing are not well understood. The Dorsal Organ Cool Cells (DOCCs) Drosophila larva a set exceptionally thermosensitive neurons critical for larval cool avoidance. Here, we show that DOCC cool-sensing is mediated by Ionotropic Receptors (IRs), family sensory receptors widely studied in invertebrate chemical sensing. We find two IRs, IR21a and IR25a, required mediate responses cooling avoidance behavior. Furthermore, ectopic expression can confer cool-responsiveness an Ir25a-dependent manner, suggesting instructive role thermosensing. Together, these data IR function together thermosensation exquisite sensitivity.

Language: Английский

---

Aedes aegypti Mosquitoes Detect Acidic Volatiles Found in Human Odor Using the IR8a Pathway

Current Biology, Journal Year: 2019, Volume and Issue: 29(8), P. 1253 - 1262.e7

Published: March 28, 2019

Language: Английский

---

Two sides of a coin: ecological and chronobiological perspectives of timing in the wild

Philosophical Transactions of the Royal Society B Biological Sciences, Journal Year: 2017, Volume and Issue: 372(1734), P. 20160246 - 20160246

Published: Oct. 9, 2017

Most processes within organisms, and most interactions between organisms their environment, have distinct time profiles. The temporal coordination of such is crucial across levels biological organization, but disciplines differ widely in approaches to study timing. Such differences are accentuated ecologists, who centrally concerned with a holistic view an organism relation its external chronobiologists, emphasize internal timekeeping the mechanisms adjustment environment. We argue that ecological chronobiological perspectives complementary, studies at intersection will enable both fields jointly overcome obstacles currently hinder progress. However, achieve this integration, we first cross some conceptual barriers, clarifying prohibitively inaccessible terminologies. critically assess main assumptions concepts either field, as well common interests. Both intersect need understand extent regulation plasticity, concept 'chronotype', i.e. characteristic properties individuals which targets natural sexual selection. then highlight promising developments, point out open questions, acknowledge difficulties propose directions for further integration through Wild Clock research.This article part themed issue 'Wild Clocks: integrating chronobiology ecology free-living animals'.

Language: Английский

---

Chemoreceptor co-expression in Drosophila melanogaster olfactory neurons

eLife, Journal Year: 2022, Volume and Issue: 11

Published: April 20, 2022

olfactory neurons have long been thought to express only one chemosensory receptor gene family. There are two main families in

Language: Английский

---

Cross-modal sensory compensation increases mosquito attraction to humans

Science Advances, Journal Year: 2025, Volume and Issue: 11(1)

Published: Jan. 1, 2025

Sensory compensation occurs when loss of one sense leads to enhanced perception by another sense. We have identified a previously undescribed mechanism sensory in female Aedes aegypti mosquitoes. Odorant receptor co-receptor ( Orco ) mutants show attraction human skin temperature and increased heat-evoked neuronal activity foreleg neurons. Ir140 , foreleg-enriched member the ionotropic (IR) superfamily receptors, is up-regulated mutant legs. double do not heat seeking seen single mutants, suggesting that up-regulation key underlying mutants. Because expression sparse legs, this requires an indirect, long-range mechanism. Our findings highlight how mosquitoes, despite suffering olfactory loss, maintain overall effectiveness their host-seeking behavior up-regulating temperature, further enhancing status as most dangerous predator humans.

Language: Английский

---

Ionotropic Receptor-dependent moist and dry cells control hygrosensation in Drosophila

eLife, Journal Year: 2017, Volume and Issue: 6

Published: June 16, 2017

Insects use hygrosensation (humidity sensing) to avoid desiccation and, in vectors such as mosquitoes, locate vertebrate hosts. Sensory neurons activated by either dry or moist air (‘dry cells’ and ‘moist cells’) have been described many insects, but their behavioral roles the molecular basis of hygrosensitivity remain unclear. We recently reported that Drosophila relies on three Ionotropic Receptors (IRs) required for cell function: IR25a, IR93a IR40a (Knecht et al., 2016). Here, we discover cells show they require IR25a together with IR68a, a conserved, orphan IR. Both IR68a- IR40a-dependent pathways drive hygrosensory behavior: each is important dry-seeking hydrated flies underlie moist-seeking dehydrated flies. These studies reveal humidity sensing Drosophila, likely other involves combined activity two molecularly related neuronally distinct hygrosensing systems.

Language: Английский

---

The genomic and functional landscapes of developmental plasticity in the American cockroach

Nature Communications, Journal Year: 2018, Volume and Issue: 9(1)

Published: March 2, 2018

Abstract Many cockroach species have adapted to urban environments, and some been serious pests of public health in the tropics subtropics. Here, we present 3.38-Gb genome a consensus gene set American cockroach, Periplaneta americana . We report insights from both genomic functional investigations into underlying basis its adaptation environments developmental plasticity. In comparison with other insects, expansions families P. exist for most core likely associated environmental adaptation, such as chemoreception detoxification. Multiple pathways regulating metamorphic development are well conserved, RNAi experiments inform on key roles 20-hydroxyecdysone, juvenile hormone, insulin, decapentaplegic signals Our analyses reveal high level sequence identity genes between two termite species, advancing it valuable model study evolutionary relationships cockroaches termites.

Language: Английский

---

A molecular and neuronal basis for amino acid sensing in the Drosophila larva

Scientific Reports, Journal Year: 2016, Volume and Issue: 6(1)

Published: Dec. 16, 2016

Abstract Amino acids are important nutrients for animals, reflected in conserved internal pathways vertebrates and invertebrates monitoring cellular levels of these compounds. In mammals, sensory cells metabotropic glutamate receptor-related taste receptors that detect environmental sources amino food also well-characterised. By contrast, it is unclear how insects perceive this class molecules through peripheral chemosensory mechanisms. Here we investigate acid sensing Drosophila melanogaster larvae, which feed ravenously to support their rapid growth. We show larvae display diverse behaviours (attraction, aversion, neutral) towards different acids, depend upon stimulus concentration. Some require IR76b, a member the variant ionotropic receptor repertoire invertebrate chemoreceptors. IR76b broadly expressed larval neurons, suggesting role as co-receptor. identify subpopulation neurons displays physiological activation by some, but not all, mediate suppression feeding high concentrations at least subset Our data reveal first elements sophisticated neuronal molecular substrate animals behave external acids.

Language: Английский

---