Show simple item record

dc.contributor.advisorMurray, Andrewen_US
dc.contributor.authorSolis, Eric Johnen_US
dc.date.accessioned2017-07-25T13:49:58Z
dash.embargo.terms2016-11-01en_US
dc.date.created2016-05en_US
dc.date.issued2016-05-14en_US
dc.date.submitted2016en_US
dc.identifier.citationSolis, Eric John. 2016. Defining the Essential Function of Yeast Hsf1 Reveals a Compact Transcriptional Program for Maintaining Eukaryotic Proteostasis. Doctoral dissertation, Harvard University, Graduate School of Arts & Sciences.en_US
dc.identifier.urihttp://nrs.harvard.edu/urn-3:HUL.InstRepos:33493256
dc.description.abstractDespite its eponymous association with proteotoxic stress, heat shock factor 1 (Hsf1 in yeast and HSF1 in mammals) is required for viability of yeast and many human cancer cells, yet its essential role remains undefined. Here we show that rapid nuclear export of Hsf1 achieved in a matter of minutes by a chemical genetics approach results in cell growth arrest in a matter of hours, which was associated with massive protein aggregation and eventual cell death. Genome-wide analyses of immediate gene expression changes induced by Hsf1 nuclear export revealed a basal transcriptional program comprising 18 genes, predominately encoding chaperones and other proteostasis factors. During heat shock, Hsf1 increases the magnitude of its transcriptional program without expanding its breadth. Strikingly, engineered Hsf1-independent co-expression of just Hsp70 and Hsp90 chaperones enabled robust cell growth in the complete absence of Hsf1. A comparative genomic analysis of mammalian fibroblasts and embryonic stem cells revealed that HSF1 lacks a basal transcriptional program but still regulates a similar set of chaperone genes during heat shock. Our work demonstrates that basal chaperone gene expression is a housekeeping mechanism controlled by Hsf1 in yeast and serves as a roadmap for defining the housekeeping function of HSF1 in many cancers. Finally, we investigate the mechanism causing age-associated inactivation of Hsf1 during replicative aging in budding yeast. Using classic and chemical-genetic tools, we demonstrate that inactivation is due to constitutive activation of the distinct General Stress Response. These experiments reveal that stress pathway crosstalk inhibits Hsf1 activation during replicative aging and under physiological stress in young cells.en_US
dc.description.sponsorshipSystems Biologyen_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoenen_US
dash.licenseLAAen_US
dc.subjectBiology, Cellen_US
dc.subjectBiology, Microbiologyen_US
dc.subjectBiology, Molecularen_US
dc.titleDefining the Essential Function of Yeast Hsf1 Reveals a Compact Transcriptional Program for Maintaining Eukaryotic Proteostasisen_US
dc.typeThesis or Dissertationen_US
dash.depositing.authorSolis, Eric Johnen_US
dc.date.available2017-07-26T07:31:02Z
thesis.degree.date2016en_US
thesis.degree.grantorGraduate School of Arts & Sciencesen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophyen_US
dc.contributor.committeeMemberDesai, Michaelen_US
dc.contributor.committeeMemberPincus, Daviden_US
dc.contributor.committeeMemberLevine, Erelen_US
dc.type.materialtexten_US
thesis.degree.departmentSystems Biologyen_US
dash.identifier.vireohttp://etds.lib.harvard.edu/gsas/admin/view/1004en_US
dc.description.keywordsHeat shock response; Hsf1; chaperones; protein folding; aggregation; stress response; cancer; aging; Msn2; Msn4en_US
dash.author.emailericjsolis@gmail.comen_US
dash.identifier.orcid0000-0001-7417-3869en_US
dash.contributor.affiliatedSolis, Eric
dc.identifier.orcid0000-0001-7417-3869


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record