# Control of actin filament networks by Arp2/3 complex and its regulators

> **NIH NIH R35** · UNIVERSITY OF OREGON · 2020 · $250,000

## Abstract

Project abstract
 Here we request funding to purchase of a Leica TIRF microscope with an iLas2 circular TIRF laser
launch. This instrument will be a critical piece of equipment in my laboratory, and will be the primary data
generator for at least half of the projects ongoing in my lab. In R35GM136319, the parent grant for this
supplement, my laboratory proposes to determine how WASP and WDS family proteins activate Arp2/3
complex to nucleate actin filaments. Determining the mechanism of these important regulatory proteins
and how they work together to assemble functional actin networks in cell depends on our ability to visualize
their activities using single molecule total internal reflection fluorescence microscopy (smTIRF). While our
lab is currently equipped with a TIRF microscope, our ability to carry out multi-wavelength smTIRF
experiments has been limited by our ability to select the optimal TIRF angle for each fluorophore during
data collection. This has prevented us from carrying out three color smTIRF experiments in which actin
and two actin regulatory proteins are labeled, each with a different fluorophore. It has also complicated our
efforts to visualize with single molecule sensitivity proteins labeled with fluorescent proteins (e.g.
mNeonGreen), limiting the kinds of experiments that we can do. Our current TIRF microscope also suffers
from uneven illumination issues that prevent us from using the entire field of view of TIRF images and
make automated data processing more challenging. Therefore, we request funds to purchase a new TIRF
microscope that will eliminate these issues, thereby greatly enhancing our ability to carry out
multiwavelength smTIRF experiments. We believe this instrument, a Leica TIRF microscope with a iLas2
circular TIRF illuminator, will greatly enhance our ability to accomplish the specific goals in the parent grant
and will increase the impact of our research on the field.

## Key facts

- **NIH application ID:** 10163397
- **Project number:** 3R35GM136319-01S1
- **Recipient organization:** UNIVERSITY OF OREGON
- **Principal Investigator:** Bradley J Nolen
- **Activity code:** R35 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $250,000
- **Award type:** 3
- **Project period:** 2020-05-01 → 2025-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10163397

## Citation

> US National Institutes of Health, RePORTER application 10163397, Control of actin filament networks by Arp2/3 complex and its regulators (3R35GM136319-01S1). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10163397. Licensed CC0.

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