The Desthiobiotin-GTP Probe from MtoZ Biolabs is a covalent labeling chemoproteomics tool designed to specifically capture and analyze the active state and functional network of GTP-binding proteins.
Product Overview
In research areas involving GTP binding and hydrolysis - such as signal transduction, vesicular transport, and cytoskeletal dynamics - functional analysis of GTPases (including Ras, Rho, and Rab families) and other GTP-binding proteins presents several key challenges:
1. Limited State-Specific Detection
Conventional antibody-based or biochemical assays often fail to directly and specifically distinguish GTP-bound (active) proteins from GDP-bound (inactive) forms or total protein abundance.
2. Lack of Global Activity Profiling Tools
There is an unmet need for technologies that enable unbiased, proteome-wide capture of diverse GTP-binding proteins within complex samples to map their dynamic activity states.
3. Low-Throughput Inhibitor Characterization
Evaluating binding affinity and selectivity of small-molecule GTPase inhibitors - such as Ras-targeting compounds - typically requires low-throughput, target-by-target biochemical assays with limited scalability for off-target assessment.
4. Fragmented Downstream Workflows
Enrichment of active GTPases is often incompatible with downstream mass spectrometry or Western blot analysis, leading to sample losses, workflow complexity, and incomplete biological information.
Advantages
✅ Covalent Labeling at Active Nucleotide-Binding Sites
The MtoZ Biolabs Desthiobiotin-GTP Probe is a nucleotide analogue in which desthiobiotin (also known as dephospho-biotin) is linked through an unstable acyl-phosphate bond. Upon depletion of endogenous nucleotides, the probe reacts covalently with conserved lysine residues in the GTP-binding pockets of GTPases and other GTP-binding proteins - including Gα subunits - directly marking functional active sites.
✅ Captures Both Active and Nucleotide-Binding Competent States
The unique probe design enables selective labeling of proteins that retain nucleotide-binding capacity, regardless of transient catalytic turnover. This allows comprehensive functional profiling of GTPase regulatory states that cannot be captured by conventional biochemical tools.
✅ High-Throughput Competitive Binding Platform
Through competitive incubation with test small-molecule inhibitors, the Desthiobiotin-GTP Probe quantitatively measures inhibitor affinity and selectivity across dozens to hundreds of endogenous GTP-binding proteins directly in cell lysates or complex biological systems. This provides a powerful strategy for drug target validation and off-target profiling in early discovery programs.
✅ Fully Compatible Downstream Analysis
The Desthiobiotin-GTP Probe supports both targeted and global downstream strategies without workflow fragmentation or sample loss. Enriched probe-labeled proteins can be resolved by SDS-PAGE followed by antibody-based Western blotting for rapid validation of known targets, while proteolytically digested, probe-modified peptides are amenable to LC-MS/MS analysis for unbiased, proteome-wide identification and quantification of GTP-binding proteins. This unified workflow enables systematic discovery of regulatory networks, novel drug targets, and small-molecule off-targets within complex biological samples.
Technical Support
1. Protocol Downloads
MtoZ Biolabs provides comprehensive experimental protocols and product manuals to help ensure smooth and reproducible workflows. For access to specific documents or detailed instructions, please contact our support team.
2. Customized Service Support
Our experienced scientists offer tailored technical assistance and customized solutions based on your specific research goals, helping you achieve optimal experimental outcomes.
3. FAQ and Expert Assistance
We provide responsive and professional technical support to address your questions efficiently. Our experts are ready to help you identify and resolve experimental challenges quickly and accurately.
