Biological Background of ARX

The Aristaless-Related Homeobox (ARX) gene encodes a paired-type homeodomain transcription factor that plays an indispensable role in the development of the central nervous system and pancreas. ARX is located on the X chromosome (Xp22.13) and is expressed predominantly in GABAergic interneurons, where it governs neuronal migration, differentiation, and axonal guidance during embryogenesis.

Mutations in ARX are associated with a broad spectrum of X-linked neurodevelopmental disorders, ranging from X-linked infantile spasms (Ohtahara syndrome, West syndrome) and Partington syndrome to non-syndromic X-linked intellectual disability (XLID). The ARX protein contains multiple conserved functional domains, including a homeodomain responsible for DNA binding, an aristaless domain, and polyalanine tracts whose expansion underlies several disease phenotypes.

Beyond the nervous system, ARX is expressed in the developing pancreas, where it is required for the specification of alpha cells and plays a role in glucagon-producing cell identity. This dual role makes ARX a compelling target for research in both neurology and metabolic disease.

Protein Expression, Purification & Quality Attributes

Recombinant Human ARX Protein (rp377590) is produced using recombinant expression systems designed to yield a biologically relevant form of the protein suitable for in vitro research applications. Recombinant expression ensures batch-to-batch consistency and eliminates variability associated with native tissue-derived preparations.

Typical quality control assessments for recombinant transcription factor proteins of this class include SDS-PAGE analysis to confirm molecular weight and purity, Western blotting to verify identity, and where applicable, functional assays such as DNA-binding activity assays to confirm biological activity. Researchers should consult the product datasheet for lot-specific certificate of analysis (CoA) data, including purity percentage, endotoxin levels, and host expression system details.

As ARX is a nuclear transcription factor with intrinsically disordered regions and polyalanine stretches, solubility and handling conditions are important practical considerations. Centrifuge briefly upon thawing and avoid repeated freeze-thaw cycles to maintain protein integrity.

Research Applications

Recombinant Human ARX Protein is a versatile reagent supporting a range of biochemical and cell-biological research applications:

• Protein–DNA Interaction Studies: As a homeodomain transcription factor, ARX can be used in electrophoretic mobility shift assays (EMSA) and chromatin immunoprecipitation (ChIP)-related in vitro binding assays to characterize its target DNA sequences and transcriptional regulatory mechanisms.
• Protein–Protein Interaction Assays: ARX interacts with co-regulators and other transcription factors. Pull-down assays and co-immunoprecipitation experiments using recombinant ARX can map interaction interfaces and identify novel binding partners.
• Antibody Development and Validation: Recombinant ARX protein serves as an antigen standard for generating and validating anti-ARX antibodies for use in immunohistochemistry (IHC), immunofluorescence (IF), and Western blotting.
• Structural and Biophysical Studies: Recombinant protein preparations support circular dichroism (CD), size-exclusion chromatography (SEC), and other biophysical characterization methods to study domain folding and effects of disease-associated mutations.
• Drug Discovery and Screening: ARX is a candidate target in epilepsy and intellectual disability research; recombinant protein can be employed in biochemical screens to identify small-molecule modulators.

Storage, Handling & Reconstitution Guidelines

Proper storage and handling of Recombinant Human ARX Protein are essential to preserve biological activity and experimental reproducibility. The following general guidelines apply to recombinant transcription factor proteins; always refer to the product-specific datasheet for confirmed conditions:

• Storage Temperature: Store at −80 °C for long-term preservation. Avoid storage at −20 °C for extended periods, as this may lead to protein degradation over time.
• Reconstitution: If supplied lyophilized, reconstitute in sterile, ultrapure water or the buffer specified in the datasheet. Allow the vial to equilibrate at room temperature for a few minutes before adding diluent. Mix gently; do not vortex.
• Aliquoting: Upon first thaw, prepare single-use aliquots to avoid repeated freeze-thaw cycles, which can reduce activity and promote aggregation.
• Working Concentration: Determine optimal working concentration empirically for each application. Pilot experiments with titration are recommended before committing to large-scale assays.
• Carrier Protein: If the formulation does not include a stabilizing carrier protein (e.g., BSA), consider adding one at 0.1–0.5% for dilute working stocks to prevent adsorption to tube surfaces.

Note: Specific buffer composition, pH, excipients, and guaranteed stability data are provided in the lot-specific Certificate of Analysis (CoA). Consult the CoA before use.

Ordering Information & Technical Support

Recombinant Human ARX Protein is available exclusively from Aladdin Scientific under SKU rp377590. This product is intended for research use only (RUO) and is not approved for diagnostic or therapeutic applications in humans.

For procurement inquiries, volume pricing, or custom formulation requests, please contact the Aladdin Scientific sales team. Technical questions regarding experimental design, recommended assay conditions, or troubleshooting can be directed to our scientific support team.

Please provide the product SKU (rp377590) and lot number when contacting support to ensure accurate and efficient assistance. The lot-specific Certificate of Analysis (CoA) can be downloaded from the Aladdin Scientific website using the lot number printed on the product label.