Computational Model of the Insect Pheromone Transduction Cascade
Figure 1
Moth pheromone-sensitive sensillum trichodeum in tip-recording conditions.
The sensillum is a small organ typically composed of 2 ORNs and 3 auxiliary cells (thecogen Th, trichogen Tr and Tormogen To), housed within a porous cuticular hair. The tight junctions between cells separate the ORN extracellular environment in two parts with different ionic compositions, the sensillar lymph bathing the outer dendritic segment (sensory) and the hemolymph bathing the inner dendrite and soma. In experimental conditions the pheromone is delivered close to the hair. The ORN electrical response is recorded extracellularly with an electrode slipped on the cut hair tip. Figures 2 and 3 give detailed views of the ORN membrane processes at the molecular level. Figure 6 gives an overview of the global electrical organization of the sensillum. Modified from [8].