Data from: Deafness due to loss of a TRPV channel eliminates mating behavior in Aedes aegypti males

Attraction and mating between male and female animals depend on effective
communication between conspecifics. However, in mosquitoes, we have only a
rudimentary understanding of the sensory cues and receptors critical for
the communication that is essential for reproductive behavior. While it is
known that male Aedes aegypti use sound to help them identify females, it
is not unclear whether sound detection is absolutely required, since other
cues such as vision may also participate in mating behavior. To determine
the effect of eliminating hearing on mating success, we knocked out the
Ae. aegypti TRPVa channel, which is a protein expressed in chordotonal
neurons in the Johnston’s organ (JO) that respond to sound-induced
movements in the antenna. Loss of trpVa eradicated sound-induced responses
from the JO, thereby abolishing hearing. Strikingly, mutation of trpVa
eliminated mating behavior in males. In contrast, trpVa-null females
mated, although this behavior was slightly delayed relative to wild-type
females. Males and females produce sounds as they beat their wings at
distinct frequencies during flight. Sound mimicking the female wingbeat
induced flight, attraction, and copulatory-like behavior in wild-type
males without females present, but not in trpVa-null males. Males are
known to modulate their wingbeat frequencies before mating in the air,
which is a phenomenon referred to as rapid frequency modulation (RFM). We
found that RFM was absent in mosquitoes lacking TRPVa. We conclude that
the requirement for trpVa and hearing for male reproductive behavior in
Aedes is absolute, as mating in the deaf males is eliminated.

雌雄动物间的吸引与交配依赖于同种个体间的有效通信。然而，对于蚊子而言，我们对生殖行为所必需的通信过程中关键的感官线索与受体的了解仍极为粗浅。尽管已知埃及伊蚊(Aedes aegypti)雄性会利用声音识别雌性，但目前尚不清楚声音探测是否为交配所绝对必需，因为视觉等其他线索也可能参与交配行为。为明确消除听觉对交配成功率的影响，我们敲除了埃及伊蚊的TRPVa通道——该蛋白表达于约氏器官(Johnston’s organ, JO)的弦音神经元中，可响应声音诱导的触角运动。trpVa基因的缺失完全消除了约氏器官对声音诱导刺激的反应，进而导致听觉丧失。令人意外的是，trpVa突变完全消除了雄性的交配行为。与之形成对比的是，trpVa敲除雌性仍可交配，尽管其交配行为相较于野生型雌性略有延迟。雌雄个体在飞行时会以不同频率振翅并产生声音。模拟雌性振翅频率的声音可在无雌性存在的情况下，诱导野生型雄性产生飞行、趋声定位及类似交配的行为，但对trpVa敲除雄性无此效果。已知雄性在空中交配前会调节其振翅频率，这一现象被称为快速频率调制(rapid frequency modulation, RFM)。我们发现，缺失TRPVa的蚊子完全丧失了快速频率调制能力。我们据此得出结论：埃及伊蚊雄性生殖行为对trpVa基因及听觉的需求是绝对的，因为听觉丧失的雄性完全无法完成交配。