Faced with myriad external insults, like temperature changes and osmolarity imbalances, cells must adjust their biochemical activities to meet ever-shifting demands. To counteract environmental challenges, or stresses, cells have evolved a collection of stress response pathways that work as corrective feedback loops to restore homeostasis when the cell is thrown out of equilibrium. Stress responses are ancient and the core pathways are conserved in all eukaryotes. Defects in these pathways - failures to restore homeostasis - can have deleterious effects, as in disease states like diabetes. Moreover, pathogens and cancers can selectively modulate and exploit stress response pathways to harness their cytoprotective functions. While decades of genetics, biochemistry and expression profiling have identified the pathways, worked out the basic activation mechanisms and revealed the target genes our current understanding of stress response pathways lacks both depth and breadth. It lacks depth in that we do not know the mechanisms that control the pathways in real-time to ensure sufficient activation upon stress and efficient deactivation once homeostasis is restored. Our understanding lacks breadth in that the pathways have generally been studied independently, neglecting potential interconnections. A quantitative and mechanistic understanding of how these pathways are regulated to restore homeostasis and knowledge of how the different stress responses operate as an interconnected network are prerequisites to effectively modulating these pathways for therapeutic purposes. In this context, I propose three specific aims to increase the depth of our understanding of the quantitative regulatory mechanisms that control stress response pathways and the breadth of our understanding of the interconnections between these responses. In the first two aims I will focus on the heat shock response, the elemental and and prototypical stress response, to reveal how phosphorylation and chaperone protein binding dynamics quantitatively regulate the activity of the transcription factor, Hsf1. In the third aim, I will focus on the interconnections between stres response pathways by building a panel of stress reporter strains that will allow simultaneous measurement of all stress responses following any genetic or environmental perturbation. The proposed research is significant because it will provide depth and breadth to our understanding of stress responses. Such understanding is a prerequisite to effectively harnessing these vital pathways for therapeutic benefit. Finally, I expect that the mechanistic systems biology approach described here will serve as a model for the quantitative investigation of pathways and networks in increasingly complex systems.

Public Health Relevance

The proposed research is relevant to the public health mission of the NIH because it addresses the fundamental mechanisms that regulate stress responses, vital pathways required to maintain homeostasis in protein folding. Breakdown of these pathways can lead to neurodegenerative diseases and other disease states like diabetes, while activation of these pathways is required to support highly malignant cancers. Deeper understanding of the molecular interactions that activate, tune and deactivate stress responses will lead to the development of therapeutic interventions to effectively target these pathways for the betterment of human health.

Agency
National Institute of Health (NIH)
Institute
Office of The Director, National Institutes of Health (OD)
Type
Early Independence Award (DP5)
Project #
4DP5OD017941-04
Application #
9135555
Study Section
Special Emphasis Panel (ZRG1-BBBP-E (53)R)
Program Officer
Basavappa, Ravi
Project Start
2013-09-19
Project End
2018-08-31
Budget Start
2016-09-01
Budget End
2017-08-31
Support Year
4
Fiscal Year
2016
Total Cost
$487,500
Indirect Cost
$237,500
Name
Whitehead Institute for Biomedical Research
Department
Type
DUNS #
120989983
City
Cambridge
State
MA
Country
United States
Zip Code
02142
Fanning, Saranna; Haque, Aftabul; Imberdis, Thibaut et al. (2018) Lipidomic Analysis of ?-Synuclein Neurotoxicity Identifies Stearoyl CoA Desaturase as a Target for Parkinson Treatment. Mol Cell :
Krakowiak, Joanna; Zheng, Xu; Patel, Nikit et al. (2018) Hsf1 and Hsp70 constitute a two-component feedback loop that regulates the yeast heat shock response. Elife 7:
Creixell, Pau; Pandey, Jai P; Palmeri, Antonio et al. (2018) Hierarchical Organization Endows the Kinase Domain with Regulatory Plasticity. Cell Syst 7:371-383.e4
Solís, Eric J; Pandey, Jai P; Zheng, Xu et al. (2018) Defining the Essential Function of Yeast Hsf1 Reveals a Compact Transcriptional Program for Maintaining Eukaryotic Proteostasis. Mol Cell 69:534
Kayatekin, Can; Amasino, Audra; Gaglia, Giorgio et al. (2018) Translocon Declogger Ste24 Protects against IAPP Oligomer-Induced Proteotoxicity. Cell 173:62-73.e9
Zheng, Xu; Beyzavi, Ali; Krakowiak, Joanna et al. (2018) Hsf1 Phosphorylation Generates Cell-to-Cell Variation in Hsp90 Levels and Promotes Phenotypic Plasticity. Cell Rep 22:3099-3106
Truttmann, Matthias C; Pincus, David; Ploegh, Hidde L (2018) Chaperone AMPylation modulates aggregation and toxicity of neurodegenerative disease-associated polypeptides. Proc Natl Acad Sci U S A 115:E5008-E5017
Pincus, David; Anandhakumar, Jayamani; Thiru, Prathapan et al. (2018) Genetic and epigenetic determinants establish a continuum of Hsf1 occupancy and activity across the yeast genome. Mol Biol Cell 29:3168-3182
Pincus, David; Pandey, Jai P; Feder, Zoë A et al. (2018) Engineering allosteric regulation in protein kinases. Sci Signal 11:
Pincus, David; Resnekov, Orna; Reynolds, Kimberly A (2017) An evolution-based strategy for engineering allosteric regulation. Phys Biol 14:025002

Showing the most recent 10 out of 19 publications