# Rare-event simulation and analysis for elucidating mechanisms of development and disease

> **NIH NIH R35** · UNIVERSITY OF CHICAGO · 2020 · $375,065

## Abstract

PROJECT SUMMARY. Molecular simulations complement experiments by revealing the microscopic dynamics
underlying biological mechanisms and the forces promoting those dynamics. However, most biological processes
involve time scales much longer than the time step of numerical integration. While there are many methods for
bridging this separation of time scales to obtain equilibrium averages, further advances are needed to robustly
estimate dynamical statistics. The proposed research seeks to develop general methods that can meet this need
and to apply them to elucidating self-assembly mechanisms at both molecular and cellular length scales.
 Improving insulin therapies through rare-event analyses of short simulations. There is a pandemic in diabetes
mellitus, with tremendous cost worldwide. The main treatment is insulin therapy, but it has a narrow therapeutic
index, and its requirement for refrigerated transport and storage is prohibitively costly for much of the world.
Insulin analogs have been engineered to have speciﬁc pharmacokinetics based on knowledge of insulin self-
association, but an understanding of how insulin binds to the insulin receptor (IR) remains lacking. We seek to
develop computational methods that can enable simulation and analysis of coupled folding and binding reactions
and to combine these methods with recently obtained structures of IR bound to insulin and single-chain insulin
(SCI) analogs to elucidate the microscopic origins of observed therapeutic activities. The study can thus ultimately
lead to improved insulin therapies. We will also investigate the improved thermal properties of SCI analogs, in
particular, their reduced tendency to form amyloid ﬁbrils. The study thus also promises to yield insights into
amyloid formation, with broad implications beyond insulin to neurodegenerative disorders like Parkinson's and
Alzheimer's diseases.
 Modeling cytoskeletal processes leading to developmental patterning. Cytoskeletal dynamics underlie diverse
processes, including developmental patterning, neuronal synapse formation, immunological recognition, wound
healing, and tumor growth. These dynamics can be very hard to intuit because they involve balances of me-
chanical forces, mechanochemistry, network assembly and dissasembly, and feedback to and from cell signaling
molecules. Models thus play an important role in parsing contributing molecular processes and testing quanti-
tative hypotheses. We will adapt a recently parameterized cytoskeletal model that is quantitatively predictive in
vitro to elucidate mechanisms of developmental patterning in vivo. Namely, we will investigate how interactions
between the small GTPase RhoA and actin assembly/dissasembly control pulsatile contractility, a widespread
phenomenon that drives cortical ﬂow, cell shape change, and tissue deformation. Then we will compare models
for the localization of the evolutionarily-conserved RNA-binding protein Staufen during anterior-posterior speci-
ﬁcation. ...

## Key facts

- **NIH application ID:** 9931990
- **Project number:** 1R35GM136381-01
- **Recipient organization:** UNIVERSITY OF CHICAGO
- **Principal Investigator:** Aaron Dinner
- **Activity code:** R35 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $375,065
- **Award type:** 1
- **Project period:** 2020-05-01 → 2025-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9931990

## Citation

> US National Institutes of Health, RePORTER application 9931990, Rare-event simulation and analysis for elucidating mechanisms of development and disease (1R35GM136381-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9931990. Licensed CC0.

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