NSF Postdoctoral Fellowship in Biology FY 2020

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2020, Research Using Biological Collections. The fellowship supports research and training of the Fellow that will utilize biological collections in innovative ways. Wild amphibians have experienced die-offs partly due to the fungal pathogen, Batrachochytrium dendrobatidis (Bd).

Bd exhibits a wide range of effects, with some amphibians showing high vulnerability to Bd infections while others appearing to be resistant. Why this is the case remains unknown and hampers efforts to protect amphibians from such die-offs. Previous research suggests a genetic basis for this variation and that wild amphibian populations could be genetically screened for susceptibility to the fungus, and then later selectively introduced from captivity as Bd-resistant amphibians into vulnerable populations.

Previous studies have attempted to understand this vulnerability by comparing laboratory-based infection patterns with Differential Gene Expression (DGE). However, these have had two major shortcomings: (1) they do not distinguish between general pathogen responses and Bd-specific responses and (2) they have not isolated Bd-response genes while also demonstrating that Bd affects the evolution of those genes.

Without this information, amphibian genetics cannot be confidently linked to vulnerability or resistance to this fungal pathogen. The Fellow will create educational outreach and research opportunities to the public and students on these topics; these will specifically pertain to disease ecology and bioinformatics as disseminated both online and in zoological settings within the USA and/or Brazil.

To evaluate the ability of DGE to identify Bd-resistance genes in amphibians, an infection experiment will be performed on Brazilian frogs from a population that rebounded following a Bd decline in the 1980s. This experiment will include three treatments: (1) control, (2) Bd infection, and (3) bacterial infection (Mycobacterium marinum). Comparing frog performance in the Bd vs. control treatments will reveal whether the population is Bd resistant.

Comparing DGE results across Bd and bacteria treatments will identify Bd-specific genes. These genes will then be sequenced from ethanol-preserved museum specimens collected prior to the 1980s outbreak. Gene sequences before and after the outbreak will be compared to assess whether an evolutionary response to Bd has taken place.

In the process, the Fellow will receive training in experimental work, DNA sequencing, and other professional training from sponsoring scientists. The Fellow will also mentor students at Cornell and in Brazil, produce bilingual (English and Portuguese) disease ecology resources, and engage in educational outreach at the Smithsonian National Zoo.

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.