EDGE: Developing techniques for linking genotype to phenotype in amphibians

Stanford University, Stanford CA

Investigators

Abstract

Amphibians have been an important model system in scientific research for centuries. Frogs and salamanders have easily accessible physiology, life cycles, and behavior that can be used to study general questions in biology. There are over 5,000 species of frogs that show a great deal of natural diversity, where each species has adapted in unique ways to its environment. Many of these species are at risk of extinction, mainly due to habitat degradation and spread of a lethal fungus throughout the world that can kill entire frog populations. The investigators of this project, together with a network of amphibian researchers, develop gene-editing tools for frogs and salamanders. The purpose of this genetic toolkit is to enable researchers to test predictions of how genes or proteins influence behavior and development, both in the pristine laboratory as well as the muddy rainforest. This project also involves training of undergraduate and graduate students, and researchers from around the world through hands-on training courses and the development of online community resources. One training course is held at Stanford University to support the training of researchers in the United States. Another, international workshop is held in South America, which holds much of the world's amphibian biodiversity. In addition, the project expands a successful regional program called the Frogger School Program to a nationwide resource with education materials for K-12 classrooms in rural and inner-city public schools. Amphibians are a diverse group of vertebrates with unique evolutionary innovations in morphology, behavior, and physiology. Most of these striking phenotypes are not represented in the few amphibian species with functional genomics tools, severely hindering progress on understanding how genetic variation influences the incredible phenotypic variation observed within this speciose group. South American poison frogs have evolved warning coloration, chemical defenses, and complex parental behaviors, where each of these traits varies both within and between species. Moreover, this suite of traits has evolved independently in some African frog species, allowing built-in replication for addressing links between genotype and phenotype. This research proposal focuses on the development of functional genomics tools in poison frogs, with plans to expand and disseminate these technologies to the broader amphibian community. Specifically, the goals of the project are to develop a general amphibian genetic toolkit to (1) enable gene disruption using CRISPR/Cas9 and morpholino technologies, (2) express transgenic materials using expression vector insertions, and (3) develop electroporation techniques to manipulate genes in specific cell types or tissues. Another goal is rapid dissemination of this toolkit through the online distribution of protocols and hands-on workshops to train the next generation of amphibian biologists to integrate newly developed, cutting-edge technologies into their research programs. Finally, an existing regional K-12 outreach program is expanded into a nationwide resource for educators and local amphibian researchers to connect with one another and bring amphibian biology, conservation, and evolution into public school classrooms. This project is co-funded by the Behavioral Systems Cluster in the Division of Integrative Organismal Systems of the Directorate for Biological Sciences. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.