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Yeast prions are self-perpetuating misfolded proteins that are infectious. In yeast, [PSI+] is the prion form of the Sup35 protein. While the study of [PSI+] has revealed important cellular mechanisms that contribute to prion propagation, the underlying cellular factors that influence prion formation are not well understood. Prion formation has been described as a multi-step process involving both the initial nucleation and growth of aggregates, followed by the subsequent transmission of prion particles to daughter cells. Prior evidence suggests that actin plays a role in this multi-step process, but actin’s precise role is unclear. Here, we investigate how actin influences the cell’s ability to manage newly formed visible aggregates and how actin influences the transmission of newly formed aggregates to future generations. At early steps, using 3D time-lapse microscopy, several actin mutants, and Markov modeling, we find that the movement of newly formed aggregates is random and actin independent. At later steps, our prion induction studies provide evidence that the transmission of newly formed prion particles to daughter cells is limited by the actin cytoskeletal network. We suspect that this limitation is because actin is used to possibly retain prion particles in the mother cell.
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This content will become publicly available on January 1, 2026
Prion Gene Sequencing in Florida Panthers (Puma concolor coryi) Suggests No Differential Susceptibility to Transmissible Spongiform Encephalopathy
Transmissible spongiform encephalopathy, or prion disease, poses a serious threat to wildlife; however, the susceptibility of apex predators is still being assessed. We investigated variation in the prion protein gene in Florida panthers (Puma concolor coryi) and found that admixture from Central American pumas probably introduced a novel, albeit benign, prion allele.
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- Award ID(s):
- 2149866
- PAR ID:
- 10609865
- Publisher / Repository:
- Allen Press
- Date Published:
- Journal Name:
- Journal of Wildlife Diseases
- Volume:
- 61
- Issue:
- 1
- ISSN:
- 0090-3558
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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