Recombinant Rat BRAK protein (Cxcl14) is produced using an E.Coli expression system and contains the complete mature protein sequence from amino acids 23 to 99. The protein appears to maintain high purity—greater than 95% based on SDS-PAGE analysis—and comes without any purification tags. Biological activity has been confirmed through chemotaxis bioassays with human monocytes, showing responsiveness at concentrations between 1.0 and 10 ng/ml. Endotoxin levels stay below 1.0 EU/µg, as determined by LAL method testing.
BRAK protein, which goes by the alternative name Cxcl14, functions as a chemokine within immune system pathways. Its primary role seems to involve chemotaxis—essentially guiding the directional movement of monocytes, those crucial white blood cells that help orchestrate immune responses. Being part of the CXC chemokine family, Cxcl14 has drawn considerable attention from researchers studying how immune cells migrate and how inflammation develops.
Potential Applications
Note: The applications listed below are based on what we know about this protein's biological functions, published research, and experience from experts in the field. However, we haven't fully tested all of these applications ourselves yet. We'd recommend running some preliminary tests first to make sure they work for your specific research goals.
1. Human Monocyte Chemotaxis Assays
This recombinant rat BRAK protein shows reliable biological activity in human monocyte chemotaxis assays within the 1.0-10 ng/ml range, which makes it particularly useful as a positive control or reference standard. Researchers often need dependable controls to validate their chemotaxis protocols, and this protein could help establish those critical dose-response curves while providing a benchmark for comparing other chemokine preparations. What's interesting is the cross-species activity—rat BRAK attracting human monocytes suggests some evolutionary conservation in chemokine signaling that researchers are eager to explore further. The combination of high purity (>95%) and minimal endotoxin contamination should translate to consistent, reproducible results in cell-based experiments.
2. Comparative Chemokine Function Studies
Having access to biologically active rat BRAK opens up opportunities for direct comparison studies with human BRAK/CXCL14 and related chemokines. This could reveal species-specific differences in how potently these proteins attract cells and how they bind to receptors. Scientists can run parallel chemotaxis assays using different immune cell types, potentially mapping out where BRAK function stays conserved across species and where it diverges. Such studies may provide insights into how chemokine networks evolved and their varying roles in immune cell movement. The established activity range gives researchers a quantitative starting point for measuring relative potency between different chemokines.
3. Antibody Development and Validation
This pure, tag-free rat BRAK protein could work well as an immunogen for creating species-specific antibodies, or serve as a standard when testing existing anti-BRAK antibodies. Since it represents the mature protein sequence (aa 23-99)—essentially the naturally processed form—it's likely to be valuable for developing antibodies that recognize the protein in its biologically relevant state. Researchers might find it useful for ELISA development, Western blot validation, and specificity testing. The confirmed biological activity means any antibodies generated can be tested against a protein that actually functions as it should.
4. Protein-Protein Interaction Studies
Biologically active rat BRAK protein can be used in biochemical assays designed to identify and characterize its binding partners—things like receptors, proteoglycans, and other components found in the extracellular matrix. Surface plasmon resonance, bio-layer interferometry, or pull-down assays could help determine binding kinetics and affinities. The absence of purification tags eliminates one potential source of interference in binding studies, which is often a concern. Low endotoxin content makes it suitable for sensitive cell-based interaction assays where bacterial contamination might skew results.
5. Structure-Function Relationship Analysis
This recombinant protein provides a solid reference point for investigating how BRAK's structure relates to its chemotactic activity, particularly through mutagenesis and functional analysis approaches. When researchers test mutant variants or chemically modified versions, they'll need a reliable wild-type standard for comparison. The established concentration range for biological activity (1.0-10 ng/ml) gives clear benchmarks for evaluating how structural changes might affect protein function. High purity should allow for accurate protein quantification, which becomes important when conducting dose-response studies or investigating structure-activity relationships.
