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Biology Seminar - Carlos Taboada - Tuesday, April 11, 2023 - 4pm

Tuesday, April 11, 2023
4:00pm to 5:00pm
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Biology Seminar

Tuesday, April 11, 2023

Reception - 3:30 pm

Seminar - 4 pm

Location - Chen 100

Carlos Taboada, Principal Investigator

Vanderbilt University

Title: ‘Hidden in the canopy: novel biochemical and vascular adaptations for camouflage and transparency in leaf-dwelling neotropical frogs'

Abstract: Hundreds of neotropical frogs evolved biochemical tricks for signaling and camouflage involving strong fluorescence, novel colored proteins, and remarkable cardiovascular mechanisms that maintain the transparency of their tissues. In particular, green treefrogs co-opted a group of serpin proteins –with ancient immunological and blood coagulation functions– that bind biliverdin and make the animals leaf-like green, matching the reflectance of the canopy to the tiniest details. These serpins (Biliverdin-binding serpins, or BBSs) constitute a novel group of near-infrared (NIR) absorbing proteins that arose more than 40 times along the evolutionary history of frogs and are responsible for one of the most striking examples of convergence in nature. Among treefrogs expressing BBSs, dozens of species -known as glassfrogs- are the only examples of transparent terrestrial vertebrates. Their optical clarity parallels that of the most transparent zebrafish models and has puzzled scientists for over a century. In this talk, I will show how glassfrogs maintain their transparency and green camouflage by balancing the concentration and distribution of their BBSs in their lymph and plasma while at the same time redirecting their red blood cells to regions of the body where they are hidden from view. By using a combination of multiple imaging techniques, including photoacoustic microscopy and tomography, ultrasound, and fluorescence imaging, I will show that glassfrogs can aggregate more than 90% of their red blood cells inside their livers while they sleep -and need to be camouflaged using BBSs- while they release them to the systemic circulation while awake and active. Last, I will discuss how the study of biodiversity can offer a seemingly limitless source of structural, biochemical, and physiological novelties and how treefrogs can inspire ideas with the potential to address a wide range of present and future issues in blood-clot research, metabolism, and in the development of novel molecular probes for multiple imaging applications.