Differences in Gene Expression Responses to Heat Shock Between Warm- and Cool-Adapted Isolates of Batrachochytrium dendrobatidis

Batrachochytrium dendrobatidis (Bd) is one of the most destructive emerging infectious diseases to impact wildlife populations in modern history. Bd displays drastically different patterns of infection, both between distinct amphibian species and between different climates; this has resulted in inconsistent data on its virulence and pathogenicity. In regions within Bd’s known thermal optimum, amphibian declines are extensive and have resulted in entire species going extinct. Yet, in regions that are suboptimal and/or variable in terms of temperature, Bd persists enzootically in local populations with little to no infection and declines associated with the presence of Bd. In this study, we heat shocked six Bd isolates, and their gene expression profiles were compared to a control treatment within the accepted thermal optimum. Two cool-adapted and four warm-adapted isolates were used to compare expression levels between groups to examine differences in their reactions to heat shock. Our results showed that in response to heat shock, cool-adapted isolates upregulated the expression of genes associated with cellular and transmembrane transport activities. Cool-adapted isolates also downregulated the expression of genes relating to peptidase production, a known virulence factor of Bd. This variation in gene expression broadly supports the hypothesis that Bd’s persistence in warm climates comes at the cost of its pathogenicity as it prioritizes on maintaining metabolic homeostasis over infectivity. These findings provide more context surrounding species extinctions by investigating the adaptive potential of Bd and its ability to spread across varying environments.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Biology

Grantor

Texas State University

Year dc:date.issued

2023

Author dc:creator

• Troupe, Chloe

Advisor dc:contributor.advisor

• Rodriguez, David

Committee members dc:contributor.committeemember

• Carlos-Shanley, Camila
• Fuess, Lauren E.

• chytridiomycosis
• fungal pathogen
• RNA sequencing

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10877/20087

OAI identifier oai:identifier

oai:digital.library.txst.edu:10877/20087