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Abstract Pathogens with persistent environmental stages can have devastating effects on wildlife communities. White-nose syndrome (WNS), caused by the fungusPseudogymnoascus destructans,has caused widespread declines in bat populations of North America. In 2009, during the early stages of the WNS investigation and before molecular techniques had been developed to readily detectP. destructansin environmental samples, we initiated this study to assess whetherP. destructanscan persist in the hibernaculum environment in the absence of its conclusive bat host and cause infections in naive bats. We transferred little brown bats (Myotis lucifugus) from an unaffected winter colony in northwest Wisconsin to twoP. destructanscontaminated hibernacula in Vermont where native bats had been excluded.Infection withP. destructanswas apparent on some bats within 8 weeks following the introduction of unexposed bats to these environments, and mortality from WNS was confirmed by histopathology at both sites 14 weeks following introduction. These results indicate that environmental exposure toP. destructansis sufficient to cause the infection and mortality associated with WNS in naive bats, which increases the probability of winter colony extirpation and complicates conservation efforts.
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Pathogenic strategies of Pseudogymnoascus destructans during torpor and arousal of hibernating bats
Millions of hibernating bats across North America have died from white-nose syndrome (WNS), an emerging disease caused by a psychrophilic (cold-loving) fungus,Pseudogymnoascus destructans, that invades their skin. Mechanisms ofP. destructansinvasion of bat epidermis remain obscure. Guided by our in vivo observations, we modeled hibernation with a newly generated little brown bat (Myotis lucifugus) keratinocyte cell line. We uncovered the stealth intracellular lifestyle ofP. destructans, which inhibits apoptosis of keratinocytes and spreads through the cells by two epidermal growth factor receptor (EGFR)–dependent mechanisms: active penetration during torpor and induced endocytosis during arousal. Melanin of endocytosedP. destructansblocks endolysosomal maturation, facilitatingP. destructanssurvival and germination after return to torpor. Blockade of EGFR abortsP. destructansentry into keratinocytes.
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- Award ID(s):
- 2301729
- PAR ID:
- 10567824
- Publisher / Repository:
- AAAS
- Date Published:
- Journal Name:
- Science
- Volume:
- 385
- Issue:
- 6705
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 194 to 200
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Pathogens with persistent environmental stages can have devastating effects on wildlife communities. White-nose syndrome (WNS), caused by the fungus Pseudogymnoascus destructans, has caused widespread declines in bat populations of North America. In 2009, during the early stages of the WNS investigation and before molecular techniques had been developed to readily detect P. destructans in environmental samples, we initiated this study to assess whether P. destructans can persist in the hibernaculum environment in the absence of its conclusive bat host and cause infections in naive bats. We transferred little brown bats (Myotis lucifugus) from an unaffected winter colony in northwest Wisconsin to two P. destructans contaminated hibernacula in Vermont where native bats had been excluded. Infection with P. destructans was apparent on some bats within 8 weeks following the introduction of unexposed bats to these environments, and mortality from WNS was confirmed by histopathology at both sites 14 weeks following introduction. These results indicate that environmental exposure to P. destructans is sufficient to cause the infection and mortality associated with WNS in naive bats, which increases the probability of winter colony extirpation and complicates conservation efforts.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/science.adn5606
