The SHOX2 antibody is a critical reagent in molecular biology, cardiac physiology, oncology, and regenerative medicine. The antibody targets the Short Stature Homeobox 2 (SHOX2) protein, a transcription factor essential in embryonic patterning, sinus node morphogenesis, and left-right asymmetry determination.
Encoded by the SHOX2 gene on chromosome 3q25-q26.1, this nuclear transcription regulator is evolutionarily conserved in vertebrates and shares homology with other homeodomain-containing proteins (NCBI Gene Database). SHOX2 antibody detection is commonly validated through Western blot, immunofluorescence, ELISA, and immunohistochemistry (IHC) techniques (NIH ImageJ).
Gene and Protein Structure of SHOX2
The SHOX2 gene comprises multiple exons, alternative splicing variants, and an evolutionarily conserved homeobox DNA-binding domain. Structural protein analysis via X-ray crystallography and homology modeling is available through the Protein Data Bank (PDB), detailing the α-helical DNA-binding domain essential for SHOX2’s transcriptional control.
The protein has a molecular weight of ~40 kDa and exhibits nuclear localization, confirmed in model organisms including Xenopus, mouse, and human embryonic stem cells (UCSF Developmental Biology).
Biological Functions of SHOX2
SHOX2 is indispensable for:
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Sinoatrial node formation
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Mesenchymal cell differentiation
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Left-right patterning in vertebrate embryos
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Pulmonary and craniofacial morphogenesis
Animal models generated at Jackson Laboratory exhibit bradycardia and conduction system defects when Shox2 is knocked out. Transcriptomics studies from NCBI GEO support high expression of SHOX2 in cardiac pacemaker cells and developing lung buds.
SHOX2 Antibody Validation and Specificity
Per NIH reproducibility guidelines, the SHOX2 antibody must be validated via:
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Genetic KO (e.g., CRISPR-Cas9 editing)
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Orthogonal detection (mass spectrometry or RNA-seq)
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Recombinant tagging (GFP, Myc, HA)
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Independent antibody comparison
Validated antibodies are documented in resources like the Antibody Registry, RRID initiative, and publications in PubMed Central.
Applications in Immunoassays
4.1 Western Blotting
SHOX2 protein bands are detected at ~40 kDa. Cell lines such as HeLa, SH-SY5Y, and iPSC-derived cardiomyocytes (from ATCC) are commonly used.
4.2 Immunohistochemistry
Human fetal lung, brainstem, and heart tissues stained with anti-SHOX2 show nuclear expression in SA node cells (NIH 3D Tissue Atlas).
4.3 Immunofluorescence
Using SHOX2 antibodies conjugated with Alexa Fluor dyes enables spatial imaging in embryonic zebrafish hearts (ZFIN.org) and organoid models (NIH BRAIN Initiative).
SHOX2 in Cancer Diagnostics
The SHOX2 gene is increasingly used as an epigenetic biomarker in cancer, especially:
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Lung cancer: SHOX2 methylation detection in bronchoalveolar lavage (BAL) and plasma is part of the Epi proLung® assay.
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Breast cancer: Upregulated SHOX2 correlates with triple-negative breast cancer (TNBC).
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Prostate cancer: SHOX2 modulates androgen-receptor activity via chromatin remodeling (NCBI Bookshelf).
Datasets from The Cancer Genome Atlas (TCGA) and GTEx validate SHOX2 overexpression across tumor types.
SHOX2 and Stem Cell Differentiation
SHOX2 is upregulated during differentiation of:
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iPSCs into pacemaker cardiomyocytes
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hESCs into pulmonary epithelial lineages
Protocols from Harvard Stem Cell Institute, NIH Stem Cell Information, and Stanford Institute for Stem Cell Biology guide SHOX2-based cardiac induction methods.
SHOX2 Antibody in Regenerative Medicine
In tissue engineering, SHOX2 is used to mark:
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Pacemaker cell differentiation
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SA node reconstitution in 3D-bioprinted hearts
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Neural crest-derived progenitor tracking
Grants from the National Heart, Lung, and Blood Institute (NHLBI) have funded regenerative protocols using SHOX2-overexpressing cells for bioelectronic implants.
Clinical Research and SHOX2 Biomarkers
Ongoing clinical trials registered at ClinicalTrials.gov are investigating:
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SHOX2 methylation as a non-invasive lung cancer biomarker
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SHOX2 expression in heart rhythm disorders
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SHOX2 in circulating tumor DNA (ctDNA) panels
Furthermore, diagnostic CPT codes for SHOX2 testing are listed in the Centers for Medicare & Medicaid Services (CMS) catalog.
Cross-Species Conservation and Model Organisms
Comparative studies on SHOX2 orthologs are available in:
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Mouse: via Mouse Genome Informatics (MGI)
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Zebrafish: via ZFIN
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Frog (Xenopus laevis): via Xenbase
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Chicken: used for embryonic node patterning studies
Evolutionary alignment shows >80% identity in the homeodomain across vertebrates, confirming its conserved regulatory roles in node formation, sympathetic innervation, and somitogenesis.
Data Portals and Genomic Resources
Researchers analyzing SHOX2 expression and methylation can utilize:
These tools support transcript mapping, differential expression, ChIP-seq enrichment zones, and CRISPR guide RNA design.
Conclusion
The SHOX2 antibody is a validated, versatile tool for exploring developmental biology, cardiac differentiation, and methylation-based diagnostics. Its wide application in basic science, cancer research, and regenerative medicine is backed by strong molecular evidence, abundant cross-species data, and ongoing clinical research initiatives funded by NIH, FDA, and CDC.
Researchers are encouraged to validate antibodies using government-supported protocols and leverage resources across .edu and .gov domains to ensure reproducibility, data integrity, and clinical relevance.