Dear Biology Students, Postdocs, and Faculty,
Next week for our Faculty Seminar Series at 1:00 p.m. on Monday, December 8th, we will have a talk by Dr. Amir Sapir of the Department of Biology and the Environment, The University of Haifa- Oranim Campus, Haifa, Israel. Dr. Sapir will present a talk titled “Why do mosquitoes bite? cholesterol is a metabolic driver of blood feeding in mosquitoes”.
Talk Abstract:
Mosquitoes experience a biphasic ecological, dietary, and metabolic life cycle, yet the
biochemical principles guiding these transitions remain poorly understood. Through dietary
engineering to establish sterol-defined larval and adult systems, we studied the possible role of
sterol and steroid metabolism in the Asian tiger mosquito Aedes albopictus (A. albopictus). Here
we show that larval development, successful metamorphosis, and adult emergence critically rely
on the conversion of environmental plant and fungal sterols into cholesterol. In adults, we
engineered an artificial blood system that allowed controlled manipulation of dietary sterols and
revealed that cholesterol is an essential metabolic driver of egg production. We further show that
females transfer substantial amounts of cholesterol to their eggs, supporting early larval
development until the dietary conversion mechanism becomes transcriptionally activated. This
activation includes the expression of the dietary sterol-to-cholesterol conversion enzyme DHCR-
24, which emerges as a key component of the regulatory transition from maternal sterols to
environmental sterols. Together, these findings reveal a biphasic strategy in which larvae depend
on conversion of plant and fungal sterols, whereas adult females acquire cholesterol from blood
for reproduction and for supplying eggs with cholesterol essential for early development, a
strategy tightly linked to mosquito ecology. Our findings highlight the central and stage-
regulated role of sterol metabolism in mosquito development, reproduction, and pathogenicity.
Some details about his research and publications can be found at:
Looking forward to seeing you!
Maya
