# Biochemical reconstitution of Wnt signaling complexes

> **NIH NIH F32** · STANFORD UNIVERSITY · 2020 · $67,446

## Abstract

Project Summary/Abstract
The Wnt/β-catenin signaling pathway regulates cell growth and proliferation during organism development and
in adulthood. Dysregulation of this pathway contributes to the progression of multiple diseases, including bone
and vascular disorders, diabetes, and several types of cancer. Secreted Wnt proteins act via the transmembrane
receptors of the Frizzled (Fzd) family and the co-receptor lipoprotein receptor-related protein 5 or 6 (LRP5/6) to
recruit the cytoplasmic protein Dishevelled (Dvl) and ultimately stabilize the transcriptional co-activator β-catenin
to promote gene transcription. Although Wnt/β-catenin signaling has been well studied in model organisms and
cell culture, molecular-level understanding of signal transduction in this therapeutically relevant pathway remains
incomplete. Dvl is known to polymerize at the plasma membrane and to interact directly with specific membrane
lipids, but the mechanisms by which these interactions contribute to β-catenin stabilization are not completely
understood. Here, we propose to investigate the initial steps of Wnt/β-catenin signaling by completing the
following aims:
Aim 1. Determine the individual contributions of Wnt, Fzd, and Dvl to LRP6 phosphorylation
Dvl-promoted phosphorylation of the Wnt co-receptor LRP5/6 is a key step leading to β-catenin-mediated
transcription. Using purified proteins reconstituted into lipid bilayer nanodiscs, we will test the model that Dvl
plays a crucial role in promoting LRP5/6 phosphorylation by concentrating receptors together with the scaffolding
protein Axin on the plasma membrane.
Aim 2. Examine the influence of membrane composition on Fzd and Dvl function
The presence of specific lipids or cholesterol in cell membranes is known to affect the function of membrane
proteins, and specific domains of Dvl have been reported to interact with membrane lipids. We will reconstitute
signaling complexes in nanodiscs of defined lipid composition to test the hypothesis that local membrane
environment alters multiple key interactions in Wnt/β-catenin signaling.
Successful completion of these aims will provide molecular-level insights into the initiating steps of Wnt/β-catenin
signaling. A full understanding of Wnt/β-catenin signaling is crucial for the development of safe, effective
therapeutics targeting this pathway, therefore the knowledge provided by this work will aid in the development
of novel targeted agents for treatment of multiple diseases.

## Key facts

- **NIH application ID:** 9823886
- **Project number:** 5F32GM126642-03
- **Recipient organization:** STANFORD UNIVERSITY
- **Principal Investigator:** Jacob P Mahoney
- **Activity code:** F32 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $67,446
- **Award type:** 5
- **Project period:** 2017-12-01 → 2020-11-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9823886

## Citation

> US National Institutes of Health, RePORTER application 9823886, Biochemical reconstitution of Wnt signaling complexes (5F32GM126642-03). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/9823886. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*