A High-Throughput Assay for Rho Guanine Nucleotide Exchange Factors Based on the Transcreener GDP Assay

Active Rho GTPases stimulate cell growth and migration, sometimes triggering tumorigenesis or invasion. Rho GEFs (guanine nucleotide exchange factors) positively regulate Rho GTPases by accelerating GDP dissociation and allowing the formation of the active GTPase-GTP complex.

By accelerating GDP dissociation, the rate limiting step of the GTPase catalytic cycle, GEFs enhance the steady state rates of GTP hydrolysis by GTPases. These changes can be detected using the Transcreener® GDP GEF Assay, which relies on a highly selective antibody and far-red fluorescent tracer to allow homogeneous detection of GDP with fluorescence readouts.

Applications for GDP GEF Assays Include:

  • Screen compound libraries for GEF inhibitors
  • Measure GTPase-GEF catalytic activity
  • Profile GEF Inhibitors

Transcreener GDP GEF Assay Principle

Sensitive Direct Detection of GDP

Direct detection of GDP allows increased sensitivity and lower interference compared to other detection methods. Unlike fluor-GTP binding assays, this method detects catalytic cycles of both GEFs and GTPases with unmodified GTP substrate, providing a more direct measure of functional GEF activity.

Universal GEF Assay Technique

Because the Transcreener GDP GEF Assay directly measures GDP production, it can be used for a variety of diverse GTPase/GEF pairs.

Flexible Assay Format

Use 96, 384, or 1536 well plates depending on your desired format.

Mix-and-Read Simplicity

The Transcreener® GDP GEF Assay is an easy to use homogeneous mix-and-read assay. This leads to easier programing and faster reads when performing high-throughput screens.

Stable Reagents and Assay Signal

The Transcreener® GDP GEF Assays are stable for a minimum of 8 hours at room temperature allowing you the flexibility to perform large automated screens.

Far Red FP, FI & TR-FRET Readouts Validated on Major Multimode Readers

Transcreener GDP GEF Assay Kits

* For custom or bulk orders (over 100,000 wells) please contact us (info@bellbrooklabs.com) for a quote.

In addition to our GDP Assays, Bellbrook Labs also offers the following products and services to aid in the drug discovery process: