How Do Insects Cope with Heat Stress?
Younghwan Kwak to Present Oct. 21st Seminar
Postdoctoral scholar Younghwan Kwak of the lab of Professor Gordon Bennett University of California, Merced, will speak on "Evolution and Stability of Interdependence in Insect–Microbe Symbioses" at the Oct 21st seminar hosted by the UC Davis Department of Entomology and Nematology.
Her seminar begins at 12:10 in 122 Briggs Hall. It also will be remote. The Zoom link: https://ucdavis.zoom.us/j/95882849672
"How do insects cope with heat stress?" she asks in her abstract. "More specifically, do their microbial partners help them withstand heat or contribute to their vulnerability? Many insects depend on bacterial symbionts to supply essential nutrients missing from their diets. Over evolutionary time, these symbionts have undergone extensive genome reduction, creating intimate dependencies between hosts and microbes. Yet whether hosts and symbionts respond similarly to heat or exhibit distinct physiological responses remains poorly understood."
"We examine these questions using the aster leafhopper and its two obligate bacterial symbionts. Using a multi-omics framework, we found contrasting molecular responses to acute heat stress that caused high host mortality within 24 hours. The host increased chaperone expression at both transcript and protein levels. In contrast, symbionts exhibited transcriptional shifts without a heat-shock response, detectable changes in protein abundance, or apparent alterations in cell ultrastructure. These findings challenge the assumption that symbionts are the more thermally vulnerable partner. Our findings also suggest that close metabolic dependence does not necessarily imply shared physiological responses to stress. Our study sheds light on the physiological complexity underlying thermal stress responses in insect–microbe partnerships, with broader implications for understanding insect vulnerability in a warming world."
Kwak describes herself as "an entomologist and evolutionary biologist studying the molecular and evolutionary mechanisms that shape and maintain tightly integrated insect–microbe symbioses."
Kwak received her master's degree in entomology from Chungnam National University, South Korea, and her doctorate in entomology from UC Riverside, under the guidance of Allison Hansen.
"My current research investigates how highly interdependent host–microbe partnerships respond to environmental change using systems biology approaches. As a woman in science and an international scholar who has trained in South Korea and the United States, I value learning from people with different experiences and perspectives, and I bring that openness to my mentorship and collaborations."
For any technical issues, contact seminar coordinator Lisa Baik, assistant professor of insect biology, at [email protected]. Her lab website is https://fightthebite.org.