Name: Video: Large-Scale Extraction of Crude Sex Pheromones from 6-Day-Old Virgin C. elegans Hermaphrodites
Uploaded: 2024-08-09T14:35:00
Description: 292 Views. Large-Scale Extraction of Crude Sex Pheromones from 6-Day-Old Virgin C. elegans Hermaphrodites

large-scale extraction of crude sex pheromones from 6-day-old virgin c. elegans hermaphrodites

Extraction and Quantification of Volatile Sex Pheromone Responses in C. elegans

The interplay between chemical communication and reproductive success is a fundamental principle across the animal kingdom1,2,3,4,5,6,7,8,9,10. Sex pheromones trigger a wide array of sexually dimorphic behaviors essential for locating mates, coordinating the steps involved in finding and attracting a partner, and ultimately promoting the propagation of a species11,12,13,14,15,16,17. Significant progress has been made in understanding pheromone signaling, but the molecular mechanisms, neural circuits, and computational processes governing these interactions often remain incompletely defined18,19,20,21,22,23,24,25,26.
The nematode Caenorhabditis elegans provides a powerful model for dissecting these questions. Notably, C. elegans exhibits an unusual reproductive strategy-hermaphrodites can self-fertilize but also outcross with males27,28,29,30,31,32,33. This flexibility requires a robust communication system to signal reproductive status. C. elegans is known for its well-characterized water-soluble pheromones, the ascarosides, which play varied roles in development, behavior, and social interactions. Recent discoveries have unveiled a distinct class of volatile sex pheromones employed by nematodes. These pheromones are specifically produced by sexually mature C. elegans and C. remanei virgin females and sperm-depleted hermaphrodites, serving as an attractant for adult males29,34,35. This attractant exhibits remarkable sexual dimorphism in its production and perception. The female somatic gonad governs the synthesis of this volatile sex pheromone, and production dynamically reflects reproductive status, ceasing upon mating and resuming several hours later29,34.
Understanding nematode sex pheromone communication provides insights into the evolution of chemical communication systems, the interplay between reproductive state and behavior, and the mechanisms underlying sexually dimorphic neural processing24,26,36,37,38,39. Studies implicate the amphid neuron AWA in males as critical for pheromone detection, with the G-protein-coupled receptor SRD-1 playing a key role in pheromone detection in males24. C. elegans is well-suited for studying animal chemical communication, especially sex pheromone signaling, due to its reliance on the olfactory system for mate-searching. While much is known about ascaroside signaling, the volatile sex pheromone system offers unique opportunities for comparison25,26,36,40,41,42,43,44,45,46,47,48,49,50, 
51,52,53,54,55,56,57. Moreover, C. elegans is a powerful genetic model organism due to its fully sequenced genome, clearly defined cellular lineage, and well-characterized olfactory mutants.
However, the complete neural circuitry involved in processing this pheromone, the computations that translate its perception into targeted mate-searching behaviors, and its biosynthesis regulation remain to be fully elucidated. Further investigations into these processes are crucial for understanding the diverse mechanisms governing animal communication and reproductive behaviors. The identification of key genes involved in pheromone synthesis, secretion, and perception promises to unveil novel molecular players in animal communication.&#160;The assays&#160;described here provide a basis to address these&#160;questions.

Author Spotlight: Examining Volatile Sex Pheromone Influence on Male C. elegans Behavior

Volatile Sex Pheromone Extraction and Chemoattraction Assay in Caenorhabditis elegans

Large-Scale Extraction of Crude Sex Pheromones from 6-Day-Old Virgin C. elegans Hermaphrodites

large-scale-extraction-crude-sex-pheromones-from-6-day-old-virgin-c

Research

JoVE Journal

Behavior

292 Views. Large-Scale Extraction of Crude Sex Pheromones from 6-Day-Old Virgin C. elegans Hermaphrodites

Video: Large-Scale Extraction of Crude Sex Pheromones from 6-Day-Old Virgin C. elegans  Hermaphrodites

Chemical communication is vital in organismal health, reproduction, and overall well-being. Understanding the molecular pathways, neural processes, and computations governing these signals remains an active area of research. The nematode Caenorhabditis elegans provides a powerful model for studying these processes as it produces a volatile sex pheromone. This pheromone is synthesized by virgin females or sperm-depleted hermaphrodites and serves as an attractant for males.
This protocol describes a detailed method for isolating the volatile sex pheromone from several C. elegans strains (WT strain N2, daf-22, and fog-2) and C. remanei. We also provide a protocol for quantifying the male chemotaxis response to the volatile sex pheromone. Our analysis utilizes measurements such as chemotaxis index (C.I.), arrival time (A.T.), and a trajectory plot to compare male responses under various conditions accurately. This method allows for robust comparisons between males of different genetic backgrounds or developmental stages. Furthermore, the experimental setup outlined here is adaptable to investigating other chemoattraction chemicals.

This protocol establishes methods for extracting and quantifying responses to the volatile sex pheromone in C. elegans, providing tools to study chemical communication and navigation trajectory.

Chemical communication is vital in organismal health, reproduction, and overall well-being. Understanding the molecular pathways, neural processes, and ...