Integr Comp Biol
July 2025
Primarily Undergraduate Institutions (PUIs) are significant academic employers of Ph.D. recipients.
View Article and Find Full Text PDFBackground: With their charismatic nighttime flashes, fireflies are a classic organismal system for studying the evolution of visual mating signals. However, across their diversity, fireflies employ a variety of mating strategies that include both chemical and visual signals. While phylogenetic evidence points to a common ancestor that relied on long-range pheromones, behavioral evidence suggests that light-dependent flashing fireflies do not use smell for mating.
View Article and Find Full Text PDFFirefly flashes are well-known visual signals used by these insects to find, identify, and choose mates. However, many firefly species have lost the ability to produce light as adults. These "unlighted" species generally lack developed adult light organs, are diurnal rather than nocturnal, and are believed to use volatile pheromones acting over a distance to locate mates.
View Article and Find Full Text PDFAnts and other eusocial insects emit and receive chemical signals to communicate important information within the colony. In ants, nestmate recognition, task allocation, and reproductive distribution of labor are largely mediated through the detection of cuticular hydrocarbons (CHCs) that cover the exoskeleton. With their large size and limited volatility, these CHCs are believed to be primarily detected through direct contact with the antennae during behavioral interactions.
View Article and Find Full Text PDFA great deal of understanding can be gleaned from direct observation of organismal growth, development, and behavior. However, direct observation can be time consuming and influence the organism through unintentional stimuli. Additionally, video capturing equipment can often be prohibitively expensive, difficult to modify to one's specific needs, and may come with unnecessary features.
View Article and Find Full Text PDFEusocial insects use cuticular hydrocarbons as components of pheromones that mediate social behaviours, such as caste and nestmate recognition, and regulation of reproduction. In ants such as Harpegnathos saltator, the queen produces a pheromone which suppresses the development of workers' ovaries and if she is removed, workers can transition to a reproductive state known as gamergate. Here we functionally characterize a subfamily of odorant receptors (Ors) with a nine-exon gene structure that have undergone a massive expansion in ants and other eusocial insects.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2017
Animals use a variety of sensory modalities-including visual, acoustic, and chemical-to sense their environment and interact with both conspecifics and other species. Such communication is especially critical in eusocial insects such as honey bees and ants, where cooperation is critical for survival and reproductive success. Various classes of chemoreceptors have been hypothesized to play essential roles in the origin and evolution of eusociality in ants, through their functional roles in pheromone detection that characterizes reproductive status and colony membership.
View Article and Find Full Text PDFInsect odorant receptors function as heteromeric odorant-gated cation channels comprising a conventional odorant-sensitive tuning receptor, and a conserved co-receptor (Orco). An Orco agonist, VUAA1, is able to activate both heteromeric and homomeric Orco-containing channels. Very little is known about specific residues in Orco that contribute to cation permeability and gating.
View Article and Find Full Text PDFInsect odorant receptors (ORs) function as heteromeric odorant-gated ion channels consisting of a conserved coreceptor, Orco, and an odorant-sensitive tuning subunit. Although some OR modulators have been identified, an extended library of pharmacological tools is currently lacking and would aid in furthering our understanding of insect OR complexes. We now demonstrate that amiloride and several derivatives, which have been extensively used as blockers for various ion channels and transporters, also block odorant-gated currents from 2 OR complexes from the malaria vector mosquito Anopheles gambiae.
View Article and Find Full Text PDFIn an environment filled with a complex spectrum of chemical stimuli, insects rely on the specificity of odorant receptors (ORs) to discern odorants of ecological importance. In nature, cyclic esters, or lactones, represent a common class of semiochemicals that exhibit a range of diversity through ring size and substituents, as well as stereochemistry. We have used heterologous expression to explore the lactone sensitivity of AgOr48, an odorant-sensitive OR from the principal malaria vector mosquito, Anopheles gambiae.
View Article and Find Full Text PDFBackground: At a molecular level, insects utilize members of several highly divergent and unrelated families of cell-surface chemosensory receptors for detection of volatile odorants. Most odors are detected via a family of odorant receptors (ORs), which form heteromeric complexes consisting of a well-conserved OR co-receptor (Orco) ion channel and a non-conserved tuning OR that provides coding specificity to each complex. Orco functions as a non-selective cation channel and is expressed in the majority of olfactory receptor neurons (ORNs).
View Article and Find Full Text PDFBackground: Insect odorant receptors (ORs) function as odorant-gated ion channels consisting of a conventional, odorant-binding OR and the Orco coreceptor. While Orco can function as a homomeric ion channel, the role(s) of the conventional OR in heteromeric OR complexes has largely focused only on odorant recognition.
Results: To investigate other roles of odorant-binding ORs, we have employed patch clamp electrophysiology to investigate the properties of the channel pore of several OR complexes formed by a range of different odorant-specific Anopheles gambiae ORs (AgOrs) each paired with AgOrco.
In insects, odor cues are discriminated through a divergent family of odorant receptors (ORs). A functional OR complex consists of both a conventional odorant-binding OR and a nonconventional coreceptor (Orco) that is highly conserved across insect taxa. Recent reports have characterized insect ORs as ion channels, but the precise mechanism of signaling remains unclear.
View Article and Find Full Text PDFAedes aegypti and Anopheles gambiae are among the best-characterized mosquito species within the Culicinae and Anophelinae mosquito clades which diverged ∼150 million years ago. Despite this evolutionary distance, the olfactory systems of these mosquitoes exhibit similar morphological and physiological adaptations. Paradoxically, mosquito odorant receptors, which lie at the heart of chemosensory signal transduction pathways, belong to a large and highly divergent gene family.
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