A Marriage of Mosquito Researchers

The Mechanisms of Love: A Marriage of Mosquito Researchers Written by Tiffany Trent

CHLOÉ LAHONDÈRE AND CLÉMENT VINAUGER

are no strangers to the vicissitudes of mosquito research. They thrive upon it. They’ve built a research partnership and a marriage upon it, in fact. Meeting in graduate school in France, they’ve traveled around the world trying to understand how mosquitoes and other blood-feeding insects such as tsetse flies and kissing bugs target humans and, thus, how they transport pathogens and parasites to their human victims. This, in fact, was what brought them after a sojourn at the University of Washington to the Department of Biochemistry and BIOTRANS program at Virginia Tech.

“We like being faculty members of the BIOTRANS program because it gives us an opportunity to meet new collaborators and talented interdisciplinary researchers,” said Lahondère, a research assistant professor in the Department of Biochemistry in the College of Agriculture and Life Sciences. They could not have chosen a better place. With collaborators in every aspect of engineering and biology, Lahondère and Vinauger have been able to develop some projects with some truly groundbreaking possibilities.

BIOTRANS faculty members are located in ten different departments and programs across three different colleges at Virginia Tech. Their research, which sits at the interface of biology and engineering, loosely falls into three categories: transport at the cellular scale, transport at the organismal scale, and transport at the environmental scale.

Lahondère and Vinauger’s interdisciplinary research combines methods from biochemistry, neuroscience, bioengineering, and chemical ecology, and spans across these different scales. They identify epidemiologically relevant behaviors and investigate the chemical, neural, and mechanical processes that underlie these behaviors.

A recent proposal, for example, promises understanding of the mechanisms behind mosquitoborne infection, especially with regards to how mosquitoes feed.

They have also been working very intensely on “understanding how mosquitoes navigate space and time,” according to Vinauger, an assistant professor in the Department of Biochemistry in the College of Agriculture and Life Sciences.

While much has been studied about the mosquito’s sense of smell and how it targets CO 2 exhalations to find victims, very little is understood about how the mosquito uses vision.

In a recent publication in Current Biology, Vinauger has gained insight into how the visual and olfactory centers of the mosquito brain interact to help mosquitoes better track their prey. When mosquitoes encounter CO 2 , they become attracted to dark, visual objects like their hosts, and the presence of CO 2 enhances their accuracy in hunting us down.

Vinauger and his research team were able to determine this by fitting the mosquitoes with tiny helmets and tethering them in a LED flight simulator, exposing the mosquitoes to puffs of CO 2 . “We monitored the mosquitoes’ responses to visual and olfactory cues by tracking wingbeat frequency, acceleration, and turning behavior,” said Vinauger.

Using calcium imaging experiments, the research team found CO 2 modulates mosquito neural responses to discrete visual stimuli.

It has become obvious to Lahondère and Vinauger that interaction between the olfactory and visual processing centers of the mosquito brain helps the insects target their victims very accurately. It’s been found that mosquitoes are changing hunting routines in response to host cues; they now recognize when people emerge from bednets in Africa and have begun hunting more often during the day than at night. Understanding how mosquitoes process information and learn, therefore, is crucial to figuring out how to create better baits and traps. Projects like this have naturally brought Lahondère and Vinauger closer together. What many people may not realize is that their partnership also relies heavily on their individual specialties and how they bring these to bear on project development after forays at the bench and in the field. Vinauger and Lahondère are eager to take on new graduate students from the BIOTRANS program; they have a multitude of projects that would fit within the theme of biological transport. Lahondère currently has two graduate students, an undergraduate student, and

a post-bac student in her lab, while Vinauger has two graduate students, a postdoc fellow and four undergraduate students in his lab. Lahondère has many projects on her docket. She’s currently trying to understand how mosquitoes who specialize in cold-blooded animals, especially frogs and snakes, are attracted to them. What are the mechanisms of attraction? She is also working on a project analyzing how local plants can be used to keep mosquitoes away, and whether or not ornamental plants attract them. “This is definitely a project that will interest all residents of Virginia,” Lahondère said. This potentially dovetails with another field project of Lahondère’s, in which she’s trapping populations throughout Virginia to see how global change will affect their populations at various elevations. For instance, Aedes japonicus, an invasive mosquito that is a vector for West

Image: Vinauger and Lahondère use a 3D printer to create helmets which they fit onto mosquitoes to study their brain activity. Photo courtesy of Vinauger and Lahondère labs.

Nile virus among other diseases, is now found at Mountain Lake Biological Station in Pembroke, Virginia. Lahondère, who is affiliated with the Global Change Center, and Vinauger have teamed up with the Philosophy department and with the department of Fish and Wildlife Conservation to understand how Virginians perceive mosquitoes and what their expectations regarding mosquitoes will be as the climate continues to change. “Currently, we’ve been amazed

to discover that only 49% of Virginians believe that climate change will have any effect. “We’re hoping to use the spread of mosquitoes as disease vectors to help people understand the effects of climate change,” Lahondère noted. Vinauger prefers to work in the lab, and with his collaborators, he is working on several projects to understand fluid mechanics as

they pertain to mosquito feeding and the extent to which the neurophysiology of mosquitoes fluctuates with time-of-day. Whether they work separately or alone, one lovely thing has come of this partnership – a son, Timotey, now almost two years old. Born at the end of their postdoctoral phase, their son has made them realize the importance of work-life balance.

“It’s hard to turn work off,” Vinauger said, “but having a child makes you realize you need to be home and spend time with him.” Despite the frenetic nature of their professional lives, the family still finds time to maintain its center. Negotiating that balance has become one of the most important mechanisms of their professional careers and their love.