Sitting outside on warm summer evenings is often accompanied by the sound of hands slapping flesh as we respond to the unwelcome embrace of mosquitoes. Mosquitoes dine on nectar for their bodily sustenance, but the females amongst them crave blood to enable them to produce eggs. When they stick their proboscis into your flesh, they inject saliva to prevent clotting. It incidentally has antimicrobial properties to inhibit bacterial growth in their nectar meals.
The body temperature of our active mosquitoes is around 70°F and that gives them a problem. When they chomp down on us, they are getting a hot meal at 98°F. Remember that they are not sipping but gulping, so they have a big spike in body temperature which is liable to mess up their body proteins. Denlinger et al of Ohio State U (1) have reported on how they handle this problem. They express a particular heat shock protein that protects their proteins from the stress caused by the sudden temperature rise in their gut.
Without this protection, their ability to digest their meal is significantly diminished, as is their ability to produce eggs. Should they decide to dine on cold-blooded amphibians, this protective protein isn’t produced. Bed bugs also use this strategy for tackling hot meals.
Being a mosquito is not such an easy life it seems. Sneaking past our defenses to get through our thick hide and get a bellyful is not the end of their problem.
