Wednesday, January 15, 2025 1/15/2025

Computational and biochemical screening for the discovery of molecules that stabilize ITPA clinical variants

Award Number: R15GM112121
ORGANIZATION: NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES
OPDIV: NIH
AWARD CLASS: DISCRETIONARY
AWARD ACTIVITY TYPE: SCIENTIFIC/HEALTH RESEARCH (INCLUDES SURVEYS)

Group Awards By:

View Award Abstract

Project Summary/Abstract Human inosine triphosphate pyrophosphohydrolase (ITPA) is a protective enzyme that is essential for life. ITPA hydrolyzes inosine triphosphate (ITP) to the monophosphate form (IMP) to keep the nucleoside triphosphate from interfering with normal cellular processes and/or incorporation into nucleic acids. The P32T variant of the enzyme can modulate the results of certain treatments for life-threatening diseases, such as cancer, while the R178C variant can cause a fatal infantile encephalopathy (DEE 35). Our long-term goal is to develop a drug that can address this orphan disease (DEE 35) and provide better outcomes for P32T individuals. Experiments and computer simulations from our previous NIH R15 funding demonstrated that the stability of P32T and R178C proteins is reduced, catalysis is severely compromised for R178C, and that both mutations disrupted the structural dynamics of lower lobe helix 2 of the enzyme. These results suggest that a small drug-like molecule could bind to clinically relevant variants of ITPA to help stabilize the protein. Our specific aims are geared towards identifying molecules that can reverse these ITPA variants defects. In collaboration with the Molecular Screening Shared Resource (MSSR) lab at UCLA, we plan to perform molecular docking-based virtual screening of 300,000 small drug-like molecules of the MSSR library. Our hypothesis is that stabilization of the R178C ITPA by a library molecule will increase enzyme activity, indicating restored activity. Specific Aim 1 will include in silico and biochemical chemical library screens. The in silico screening will be performed at Eastern Washington University (EWU) and the compounds will be ranked based on the binding affinity estimation score. At UCLA, we will perform high throughput screening (HTS) experiments using a standard biochemical assay to test the enzymatic activity of R178C ITPA in presence of the top-ranked compounds obtained from the in silico virtual screening approaches. Data generated from reactions containing library molecules will be statistically evaluated and those that significantly increase ITPA activity will be considered a “hit” molecule and will be further studied at EWU using biochemical methods (Specific Aim 2) and molecular dynamic (MD) simulations (Specific Aim 3). The confirmatory biochemistry experiments will include an HPLC-based enzyme assay with wild-type, P32T and R178C ITPA enzymes. These experiments will provide kinetic parameters and EC50 values, which will help evaluate each hit molecule and gain insight into how the hit molecule affects enzyme activity. The MD simulations will confirm the stability of the binding and elucidate the dynamic of the interaction of the hit compounds with the variants binding site. Undergraduate researchers will take part in every step of the project and participate in computational and biochemical experiments at EWU and HTS experiments at UCLA. This proposal is innovative because it explores a new avenue for addressing health issues for patients with ITPA variation. The project is significant because it will provide a platform for drug discovery to address ITPA defects.


Issue Date FY	Funding FY	Legal Entity Name	Legal Entity Address	Legal Entity City	Legal Entity State	Legal Entity Zip Code	Legal Entity COUNTY	Legal Entity COUNTRY	Assistance Listing	Award Code	Budget Year	Action Date	Action Type	Action Amount

Issue Date FY: 2024 ( Subtotal = $354,861 )
2024	2024	EASTERN WASHINGTON UNIVERSITY	319 SHOWALTER HALL	CHENEY	WA	99004	SPOKANE	USA	Biomedical Research and Research Training	000	2	9/18/2024	COMPETING CONTINUATION	$354,861
														Subtotal = $354,861

Issue Date FY: 2019 ( Subtotal = -$1,957 )
2019	2015	EASTERN WASHINGTON UNIVERSITY	307 SHOWALTER HALL	CHENEY	WA	99004	SPOKANE	USA	Biomedical Research and Research Training	000	1	9/17/2019	NEW	-$1,957
														Subtotal = -$1,957

Issue Date FY: 2015 ( Subtotal = $297,967 )
2015	2015	EASTERN WASHINGTON UNIVERSITY	307 SHOWALTER HALL	CHENEY	WA	99004	SPOKANE	USA	Biomedical Research and Research Training	000	1	4/8/2015	NEW	$297,967
														Subtotal = $297,967

Grand Total All Awards = $650,871

Top

All Categories

About

Search

Reports

Data Submission

Award Information

Computational and biochemical screening for the discovery of molecules that stabilize ITPA clinical variants

Award Number: R15GM112121

ORGANIZATION: NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES

OPDIV: NIH

AWARD CLASS: DISCRETIONARY

AWARD ACTIVITY TYPE: SCIENTIFIC/HEALTH RESEARCH (INCLUDES SURVEYS)

Federal Websites

Department of Health & Human Services

HHS Operating Divisions

HHS Staff Divisions

Download A Document Viewer