Influence of blood meal on the responsiveness of olfactory receptor neurons in antennal sensilla trichodea of the yellow fever mosquito, Aedes aegypti

Abstract

housed in grooved peg sensilla on the antennae of Ae. aegypti down-regulate their sensi-4 tivity to lactic acid, a key component driving host-seeking behavior, which correlates 5 with observed changes in the host-seeking behavior of this species. In the present study, 6we performed electrophysiological recordings from the most abundant antennal sensillum 7 type, sensilla trichodea. Our results indicate that the response spectra of ORNs contained 8 within most trichoid sensilla do not change in response to blood feeding. However, we 9 observe an increase in sensitivity to primarily indole and phenolic compounds in neurons 10 housed within four of the five functional types of short blunt tipped II trichoid sensilla, 11 both at 24 h and 72 h post blood feeding, which was more pronounced at 24 h than 72 h. 12 Furthermore, sensitivity to undecanone, acetic acid and propionic acid was observed to 13 increase 72 h post blood meal. Considering the timing of these changes, we believe that 14 these neurons may be involved in driving the orientation behavior of female mosquitoes 15 to oviposition sites, which are known to release these compounds. 16 17

Olfaction in vector-host interactions

“…gambiae (Kwon et al 2006), Ae. aegypti (Ghaninia et al 2007b, Siju et al 2010 and Cx. quinquefasciatus (Hill et al 2009, Syed and Historically, kairomone-responding ORNs have been considered, with a few exceptions, to be broadly tuned (e.g.…”

“…Comparisons among the three mosquito species' ORN response profiles reveal that these organisms, which have maintained a similar host choice during evolutionary separation, employ distinct patterns of odour tuning in the ORNs. Although many similar volatiles are recognised by all three species, there appears to be little conservation in the individual ORN tuning curves (Ghaninia et al 2007a, Hill et al 2009, Siju et al 2010.…”

Blood meal-induced changes to antennal transcriptome profiles reveal shifts in odor sensitivities in Anopheles gambiae

“…gambiae females are refractory to host odor stimulation for a prolonged period after a blood meal (9), which correlates with reduced electrophysiological responses to some odors during the same period (10). Post-blood meal reductions in olfactory responses have also been shown in the yellow fever mosquito, Aedes aegypti, indicating that modulation of odor sensitivity may be a general characteristic of anautogenous mosquitoes (11).…”

Neural mechanisms of context-dependent processing of CO2 avoidance behavior in fruit flies

“…Previous research suggested that modulation in the sensory neuron changes olfactory sensitivity of mosquitoes before and after a blood meal. 33 Thus, it is possible that similar pathway modifications as we have described for Drosophila melanogaster apply to mosquitoes.…”