Ribonucleotides are small molecules that are fundamentally important to almost all cellular processes. They are the building blocks of DNA and RNA, are important precursors and intermediates in cellular metabolism, provide energy to drive cellular processes, and play important roles in regulating cellular activity. Because of thei central importance the production of new ribonucleotides is very tightly controlled in cells. One way the cell controls both the number of ribonucleotides and the balance between different types of nucleotides is to modulate the activity of two critically important enzymes, CTPS and IMPDH. Because of their critical roles in regulating ribonucleotide abundance and balance, CTPS and IMPDH are important drug targets for both chemotherapy and anti-parasitic applications, and IMPDH is implicated in human diseases that lead to blindness. While CTPS and IMPDH have been studied in detail for decades we only very recently learned that the enzymes co-assemble into large-scale structures that are important in maintaining metabolic balance in the cell. This discovery has created new areas of research that are changing the way we think about the regulation of metabolic enzymes and has opened up new possibilities for targeted drug design. This proposal aims to understand at the molecular level how CTPS and IMPDH assemble into large-scale structures, how these structures influence the activity of the enzymes, and how the celll manipulates these structures to maintain optimal ribonucleotide levels.

Public Health Relevance

Maintaining metabolic balance inside cells in critically important for human health, and imbalances can lead to disease. This proposal aims to uncover the molecular basis for maintaining healthy metabolic balance by examining a newly discovered class of cellular structures that regulate metabolism. This work will inform our understanding of how healthy cells function, how imbalance leads to disease, and provide novel targets for both chemotherapy and anti-parasitic drugs.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM118396-04
Application #
9668162
Study Section
Macromolecular Structure and Function C Study Section (MSFC)
Program Officer
Ainsztein, Alexandra M
Project Start
2016-04-01
Project End
2021-03-31
Budget Start
2019-04-01
Budget End
2020-03-31
Support Year
4
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of Washington
Department
Biochemistry
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Duong-Ly, Krisna C; Kuo, Yin-Ming; Johnson, Matthew C et al. (2018) T cell activation triggers reversible inosine-5'-monophosphate dehydrogenase assembly. J Cell Sci 131:
Lynch, Eric M; Hicks, Derrick R; Shepherd, Matthew et al. (2017) Human CTP synthase filament structure reveals the active enzyme conformation. Nat Struct Mol Biol 24:507-514
Decarreau, Justin; Wagenbach, Michael; Lynch, Eric et al. (2017) The tetrameric kinesin Kif25 suppresses pre-mitotic centrosome separation to establish proper spindle orientation. Nat Cell Biol 19:384-390
Snijder, Joost; Borst, Andrew J; Dosey, Annie et al. (2017) Vitrification after multiple rounds of sample application and blotting improves particle density on cryo-electron microscopy grids. J Struct Biol 198:38-42
Anthony, Sajitha A; Burrell, Anika L; Johnson, Matthew C et al. (2017) Reconstituted IMPDH polymers accommodate both catalytically active and inactive conformations. Mol Biol Cell :
Webb, Bradley A; Dosey, Anne M; Wittmann, Torsten et al. (2017) The glycolytic enzyme phosphofructokinase-1 assembles into filaments. J Cell Biol 216:2305-2313