Title:
Interactions of the chaperones and components of UB system in the formation and propagation of the yeast prion [PSI+]

dc.contributor.advisor Chernoff, Yury O.
dc.contributor.author Tennant, Esther Paula en_US
dc.contributor.committeeMember Choi, Jung H.
dc.contributor.committeeMember Lobachev, Kirill
dc.contributor.department Biology en_US
dc.date.accessioned 2005-09-16T15:04:36Z
dc.date.available 2005-09-16T15:04:36Z
dc.date.issued 2005-06-28 en_US
dc.description.abstract Three of the best-characterized prions of Saccharomyces cerevisiae are [PSI+], [URE3], and [PIN+]. This study focuses on the prions [PSI+] and [PIN+]. [PSI+] is the prion isoforms of the protein Sup35 that functions as a eRF3 translational termination factor. The presence of [PSI+] is detected by the partial loss of function of Sup35. The prion [PIN+] is the isoform of the protein Rnq1, and this proteins function is unknown. The presence of the prion [PIN+] is necessary for the de novo formation of the prion [PSI+] (Derkatch et al., 1997). The chaperone, Hsp104, belongs to an evolutionary conserved Hsp100 family of proteins that participate in a various number of cellular processes (Schirmer et al., 1996). Hsp104, in particular, is responsible for the cells adaptation to heat shock, it controls spore viability and the long-term viability of starving vegetative cells. (Sanchez and Linquist, 1990; Sanchez et al.,1992) It is an ATPase that has been shown to promote solubilization of aggregated protein (Parsel et al., 1991). A unique relationship exists between Hsp104 levels within the cell and the maintenance of the prion [PSI+]. The over production of Hsp104 eliminates [PSI+] (Chernoff 1995). This seems logical considering Hsp104 is a disaggregase, and it is reasonable to assume that the over production provides sufficient resources to break the aggregates into portions that are accessible to either other chaperones which would facilitate the proper folding or perhaps the system responsible for the elimination of unusable proteins, such as the ubiquitin-proteasome system. This study examines the role of the ubiquitin-proteasome system in curing of [PSI+] by Hsp104. The role of alternate pathways, in which the prion isoform is refolded into it correct, functional conformation by the action of the chaperones Ssb1 and Ssb2 is examined. These results suggest that the combination of both the degradation pathway and the refolding of proteins are involved in curing of [PSI+] by Hsp104 over production. en_US
dc.description.degree M.S. en_US
dc.format.extent 1255424 bytes
dc.format.mimetype application/pdf
dc.identifier.uri http://hdl.handle.net/1853/7157
dc.language.iso en_US
dc.publisher Georgia Institute of Technology en_US
dc.subject Ubiquitin en_US
dc.subject Proteasome
dc.subject Chaperones
dc.title Interactions of the chaperones and components of UB system in the formation and propagation of the yeast prion [PSI+] en_US
dc.type Text
dc.type.genre Thesis
dspace.entity.type Publication
local.contributor.advisor Chernoff, Yury O.
local.contributor.corporatename College of Sciences
local.contributor.corporatename School of Biological Sciences
relation.isAdvisorOfPublication d9f3d192-f4c7-4db2-ace4-2baadbeb98b6
relation.isOrgUnitOfPublication 85042be6-2d68-4e07-b384-e1f908fae48a
relation.isOrgUnitOfPublication c8b3bd08-9989-40d3-afe3-e0ad8d5c72b5
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
esther_tennant_p_200505_mast.pdf
Size:
1.2 MB
Format:
Adobe Portable Document Format
Description: