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Yeast prions [URE3] and [PSI+] are diseases.

ABSTRACT: Viruses, plasmids, and prions can spread in nature despite being a burden to their hosts. Because a prion arises de novo in more than one in 10(6) yeast cells and spreads to all offspring in meiosis, its absence in wild strains would imply that it has a net deleterious effect on its host. Among 70 wild Saccharomyces strains, we found the [PIN+] prion in 11 strains, but the [URE3] and [PSI+] prions were uniformly absent. In contrast, the "selfish" 2mu DNA was in 38 wild strains and the selfish RNA replicons L-BC, 20S, and 23S were found in 8, 14, and 1 strains, respectively. The absence of [URE3] and [PSI+] in wild strains indicates that each prion has a net deleterious effect on its host.

SUBMITTER: Nakayashiki T

PROVIDER: S-EPMC1180808 | biostudies-other | 2005 Jul

REPOSITORIES: biostudies-other

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Yeast prions [URE3] and [PSI+] are diseases.

Nakayashiki Toru T Kurtzman Cletus P CP Edskes Herman K HK Wickner Reed B RB

Proceedings of the National Academy of Sciences of the United States of America 20050715 30

Viruses, plasmids, and prions can spread in nature despite being a burden to their hosts. Because a prion arises de novo in more than one in 10(6) yeast cells and spreads to all offspring in meiosis, its absence in wild strains would imply that it has a net deleterious effect on its host. Among 70 wild Saccharomyces strains, we found the [PIN+] prion in 11 strains, but the [URE3] and [PSI+] prions were uniformly absent. In contrast, the "selfish" 2mu DNA was in 38 wild strains and the selfish RN ...[more]

PMID: 16024723

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