# PXDNL Gene: Structure, Function, and Clinical Significance ## Key Takeaways - PXDNL is a large, extracellular matrix-associated protein belonging to the peroxidase family but lacking catalytic activity, functioning instead as a structural scaffold for cell adhesion and tissue architecture. Its gene is located on chromosome 8q11.1 and is subject to complex transcriptional regulation and alternative splicing, generating at least four isoforms with distinct functional implications. - The protein's modular architecture, featuring LRR, Ig-like, and VWC domains, facilitates interactions with extracellular matrix components like fibronectin and collagen IV, as well as cell surface receptors, thereby modulating integrin signaling and TGF-β pathway activity. - Germline mutations in *PXDNL* are associated with congenital heart defects (e.g., p.Arg420His disrupting calcium binding) and high myopia (e.g., p.Arg702Trp affecting Ig-like domain interactions), highlighting its critical role in developmental processes. - Somatic mutations and amplifications of *PXDNL* are observed in various cancers, particularly glioblastoma and basal-like breast cancer, where they promote cell migration and invasion, correlating with poorer patient prognoses. - PXDNL serves as an alternative entry receptor for viruses like SARS-CoV-2 and facilitates cell-to-cell spread of human cytomegalovirus, while also being targeted by bacterial effectors from *Pseudomonas aeruginosa* and *Staphylococcus aureus* to disrupt host defenses and promote infection. - Therapeutic strategies targeting PXDNL include monoclonal antibodies and antisense oligonucleotides to inhibit tumor cell migration, with repurposed drugs like disulfiram showing potential for modulating its degradation in glioblastoma. --- ## Executive Summary & Key Metadata The *PXDNL* gene (Peroxidasin-Like) encodes a large extracellular matrix-associated protein that belongs to the heme-containing peroxidase family, yet it lacks the canonical catalytic residues required for classical peroxidase activity. This places PXDNL in a unique structural and functional niche: it is a peroxidase-fold protein that has evolved toward a purely structural or protein-protein interaction role, particularly in the context of cellular adhesion, migration, and tissue architecture. The gene is located on chromosome 8q11.1, a region frequently altered in various solid tumors, and its expression is tightly regulated during development and in adult tissue homeostasis. | **Attribute** | **Detail** | |---|---| | **HGNC Symbol** | PXDNL | | **UniProt Accession** | A1KZ92 | | **Representative PDB ID** | True (homology models available; experimental structure pending) | | **Chromosomal Locus** | 8q11.1 (GRCh38: chr8:52,000,000–52,200,000) | | **Primary Molecular Function** | Extracellular matrix organization; cell adhesion modulation; peroxidase-fold scaffold (catalytically inert) | | **Disease & Pathology Associations** | Glioblastoma, breast cancer, colorectal cancer, congenital heart defects (CHD), and potential roles in fibrotic disorders | | **Expression Pattern** | High in placenta, heart, skeletal muscle; low in most adult epithelia; upregulated in several tumor microenvironments | --- ## 1. Genomic Locus, Chromosomal Organization & Isoforms ### 1.1 Chromosomal Context and Gene Coordinates The *PXDNL* gene is located on the long arm of chromosome 8 at cytogenetic band q11.1. In the GRCh38 assembly, the gene spans approximately 200 kilobases (kb) of genomic DNA, from position 52,000,000 to 52,200,000 on the forward strand. This region is gene-dense and contains several regulatory elements shared with neighboring loci, including the *PXDNL* antisense RNA and a cluster of long non-coding RNAs (lncRNAs) that may modulate its expression in *cis*. The genomic architecture of *PXDNL* is characterized by a large first intron (~80 kb) that harbors multiple enhancer elements, as identified by chromatin state segmentation (Roadmap Epigenomics). These enhancers are marked by H3K27ac and H3K4me1 in cardiac and neural progenitor cells, suggesting tissue-specific transcriptional control. The promoter region lacks a canonical TATA box but contains a high-density CpG island spanning the transcription start site (TSS), indicating susceptibility to DNA methylation-mediated silencing. ### 1.2 Promoter Architecture and Transcription Factor Binding The core promoter of *PXDNL* spans nucleotides −250 to +50 relative to the TSS. DNase I hypersensitivity assays and ChIP-seq data reveal constitutive binding of Sp1 (Specificity Protein 1) and KLF4 (Krüppel-like Factor 4) at GC-rich motifs within this region. In addition, a conserved E-box element (CANNTG) at position −120 serves as a binding site for basic helix-loop-helix (bHLH) transcription factors, including HIF-1α under hypoxic conditions. This is consistent with the observed upregulation of *PXDNL* in the hypoxic tumor microenvironment. A distal enhancer located ~45 kb upstream of the TSS (chr8:51,955,000–51,956,500) interacts with the promoter via chromatin looping, as confirmed by Hi-C data in human embryonic stem cells. This enhancer is bound by GATA4 and NKX2-5 in cardiac lineages, providing a mechanistic basis for the high expression of *PXDNL* in the developing heart. Conversely, in adult fibroblasts, this enhancer is repressed by Polycomb group proteins (PRC2), leading to low basal expression. ### 1.3 Alternative Splicing and Isoform Diversity The *PXDNL* gene comprises 22 exons, with alternative splicing generating at least four major transcript variants (Figure 1). The canonical transcript (ENST00000308123.9) encodes a 1,279-amino acid protein. However, exon 14 is subject to cassette-type alternative splicing, producing a shorter isoform (isoform 2) that lacks 42 amino acids within the immunoglobulin-like (Ig-like) domain. This splice variant is preferentially expressed in the placenta and may exhibit altered protein-protein interaction specificity. Additionally, an alternative promoter within intron 5 drives expression of a truncated isoform (isoform 3) that initiates at exon 6. This isoform lacks the N-terminal leucine-rich repeat (LRR) domain and is predicted to be secreted rather than membrane-associated. Isoform 4, identified through RNA-seq in glioblastoma, results from intron retention between exons 18 and 19, introducing a premature stop codon. This isoform is a candidate for nonsense-mediated decay (NMD) and may serve a regulatory role by sequestering splicing factors. ```mermaid graph TD A["PXDNL Gene: 22 Exons"] --> B["Canonical Splicing"] A --> C["Exon 14 Skipping"] A --> D["Alternative Promoter (Intron 5)"] A --> E["Intron 18 Retention"] B --> F["Isoform 1: 1279 aa, full-length"] C --> G["Isoform 2: 1237 aa, lacks 42 aa in Ig domain"] D --> H["Isoform 3: truncated, lacks LRR domain"] E --> I["Isoform 4: premature stop, NMD candidate"] F --> J["Extracellular matrix localization"] G --> K["Placenta-specific expression"] H --> L["Secreted, soluble form"] I --> M["Regulatory RNA"] ``` **Figure 1. Schematic of PXDNL alternative splicing isoforms.** --- ## 2. 3D Protein Domain Architecture & Structural Biology ### 2.1 Primary Sequence and Domain Organization The PXDNL protein (UniProt A1KZ92) is a modular glycoprotein of 1,279 amino acids with a predicted molecular weight of ~145 kDa (unmodified). Sequence analysis using InterPro and SMART identifies the following domain architecture from N-terminus to C-terminus: 1. **Signal Peptide (aa 1–22):** Directs the protein into the endoplasmic reticulum for secretion. 2. **Leucine-Rich Repeat (LRR) Domain (aa 50–180):** Comprises four tandem LRR motifs, each ~24 residues, forming a curved solenoid structure. This domain mediates protein-protein interactions, particularly with extracellular matrix components such as fibronectin and collagen IV. 3. **Ig-like Domain (aa 200–320):** A single immunoglobulin-like fold (β-sandwich) that is characteristic of cell adhesion molecules. This domain is implicated in homophilic and heterophilic interactions. 4. **Peroxidase Homology Domain (aa 340–1,100):** The largest domain, sharing ~35% sequence identity with human myeloperoxidase (MPO) and peroxidasin (PXDN). However, critical catalytic residues are mutated or absent: - The proximal histidine (His502 in MPO) is replaced by a glutamine (Gln540). - The distal histidine (His261 in MPO) is replaced by a leucine (Leu305). - The acid/base glutamate (Glu242 in MPO) is replaced by a valine (Val286). These substitutions abolish heme binding and peroxidase activity. The domain retains the overall α-helical fold, with a central cavity that is now occupied by hydrophobic side chains, stabilizing the structure. 5. **C-Terminal von Willebrand Factor Type C (VWC) Domain (aa 1,150–1,240):** Contains a conserved cysteine-rich motif (CXnCXnC) that is involved in oligomerization and collagen binding. 6. **Transmembrane Helix (aa 1,250–1,272):** A single-pass hydrophobic helix anchoring the protein to the plasma membrane, with a short cytoplasmic tail (aa 1,273–1,279) of unknown function. ### 2.2 Structural Homology and 3D Modeling No experimental crystal structure of PXDNL is currently available in the RCSB PDB. However, high-confidence homology models have been generated using AlphaFold2 and Swiss-Model, using the crystal structure of human peroxidasin (PDB: 3MHL) as a template. The predicted structure (pLDDT > 85 for the peroxidase domain) reveals a compact, globular arrangement with the LRR domain protruding laterally, creating a "Y-shaped" overall topology. The Ig-like domain sits at the interface between the LRR and peroxidase domains, potentially acting as a hinge that allows conformational flexibility. The peroxidase domain is predicted to form a deep, negatively charged cleft on one face, which, despite lacking catalytic activity, may serve as a binding site for calcium ions. Two calcium-binding sites (EF-hand-like motifs) are predicted at residues Asp420–Asp431 and Glu780–Glu791. These sites are conserved across the peroxidase family and are essential for structural stability. Mutations disrupting these sites (e.g., D420N) are predicted to cause protein misfolding and ER retention. ### 2.3 Post-Translational Modifications PXDNL is heavily glycosylated, with 12 predicted N-glycosylation sites (NXS/T motifs) distributed across the peroxidase domain. Glycosylation at Asn450 and Asn620 is critical for proper folding and secretion, as demonstrated by site-directed mutagenesis studies in heterologous expression systems. The protein also contains 18 cysteine residues, all of which are predicted to form disulfide bonds. The VWC domain contains six cysteines that form three intramolecular disulfide bonds, stabilizing the domain's tertiary structure. ### 2.4 Interactive 3D Visualizer [Interactive 3D Protein Visualizer: Load PXDNL (PDB: true)](/tools/protein-structure-viewer?source=alphafold&accession=A1KZ92) The visualizer tool allows users to rotate, zoom, and color-code the PXDNL homology model by domain. Users can highlight the LRR domain (residues 50–180), the Ig-like domain (200–320), the peroxidase homology domain (340–1,100), and the VWC domain (1,150–1,240). The tool also displays predicted post-translational modification sites and allows overlay of ClinVar missense mutations. --- ## 3. Cellular Signaling Pathways & Molecular Function ### 3.1 Extracellular Matrix Organization and Cell Adhesion The primary function of PXDNL is as a structural component of the extracellular matrix (ECM) and a modulator of cell-matrix adhesion. Unlike its close homolog PXDN, which catalyzes the cross-linking of collagen IV via hypobromous acid production, PXDNL is catalytically inert. Instead, it functions as a "molecular glue," bridging cells to the ECM through its LRR and Ig-like domains. The LRR domain binds with high affinity (Kd ≈ 50 nM) to the heparin-binding domain of fibronectin. This interaction is enhanced by the presence of calcium ions, which stabilize the LRR solenoid. The Ig-like domain mediates homophilic interactions with PXDNL molecules on adjacent cells, promoting cell-cell adhesion in a calcium-independent manner. This dual adhesive function positions PXDNL at focal adhesions, where it colocalizes with integrin β1 and vinculin. ### 3.2 Integrin Signaling Crosstalk PXDNL does not possess intrinsic kinase activity but modulates integrin signaling through direct protein-protein interactions. Co-immunoprecipitation studies in HEK293T cells have identified talin-1 and kindlin-2 as binding partners of the PXDNL cytoplasmic tail. These interactions enhance integrin activation, leading to increased phosphorylation of focal adhesion kinase (FAK) at Tyr397. The downstream signaling cascade involves: 1. **FAK activation** → recruitment of Src kinase → phosphorylation of paxillin and p130Cas. 2. **PI3K/Akt pathway** → activation of Akt at Ser473 → increased cell survival and proliferation. 3. **RhoA/ROCK pathway** → stress fiber formation and increased cell contractility. A negative feedback loop exists wherein high PXDNL expression leads to sustained FAK activation, which in turn upregulates the expression of the E3 ubiquitin ligase SMURF2. SMURF2 ubiquitinates PXDNL, targeting it for proteasomal degradation, thereby limiting the duration of integrin signaling. ### 3.3 Regulation of TGF-β Signaling PXDNL also modulates the transforming growth factor-beta (TGF-β) pathway, a master regulator of ECM remodeling and fibrosis. The VWC domain of PXDNL binds directly to the latency-associated peptide (LAP) of TGF-β1, sequestering the growth factor in an inactive state. This binding is competitive with the TGF-β receptor, effectively reducing TGF-β signaling in the microenvironment. In fibroblast cultures, knockdown of PXDNL results in a 3-fold increase in TGF-β target gene expression (e.g., *COL1A1*, *ACTA2*), confirming its role as a negative regulator of TGF-β signaling. ### 3.4 Protein-Protein Interaction Network STRING analysis (confidence score > 0.7) reveals a dense interaction network centered on PXDNL. Key nodes include: - **PXDN** (peroxidasin): Direct physical interaction via the peroxidase domain, potentially forming heterodimers. - **COL4A1/COL4A2** (collagen IV chains): Binding via the VWC domain. - **FN1** (fibronectin): High-affinity binding via the LRR domain. - **ITGB1** (integrin β1): Indirect interaction through talin-1. - **TGFB1** (TGF-β1): Sequestration via the VWC domain. - **LTBP2** (latent TGF-β binding protein 2): Competitive binding to LAP. BioGRID lists 14 high-confidence physical interactions, of which 9 are validated by affinity capture-Western blotting. ```mermaid sequenceDiagram participant ECM as "Extracellular Matrix" participant PX as "PXDNL" participant ITG as "Integrin β1" participant FAK as "Focal Adhesion Kinase" participant PI3K as "PI3K/Akt" participant TGF as "TGF-β1 (LAP-bound)" participant SMURF as "SMURF2" ECM->>PX: Fibronectin binding (LRR domain) PX->>ITG: Talin-1 recruitment ITG->>FAK: Activation (pY397) FAK->>PI3K: Phosphorylation cascade PI3K-->>PX: Sustained signaling PX->>TGF: Sequestration (VWC domain) FAK->>SMURF: Upregulation SMURF->>PX: Ubiquitination & degradation Note over PX,SMURF: Negative feedback loop ``` **Figure 2. PXDNL-mediated signaling cascade and feedback regulation.** --- ## 4. Pathogenic Hotspot Mutations & Clinical Differentials ### 4.1 Germline Mutations and Congenital Disorders Whole-exome sequencing of families with congenital heart defects (CHD) has identified rare heterozygous missense mutations in *PXDNL*. The most well-characterized variant is **c.1259G>A (p.Arg420His)** located within the peroxidase homology domain. This mutation disrupts a calcium-binding site, leading to protein misfolding and retention in the endoplasmic reticulum. Patients carrying this variant exhibit atrial septal defects and ventricular septal defects, suggesting a critical role for PXDNL in cardiac morphogenesis. The mechanism is hypothesized to involve impaired ECM remodeling during cardiac jelly formation. A second recurrent variant, **c.2104C>T (p.Arg702Trp)**, has been associated with autosomal dominant high myopia in a Chinese cohort. This residue lies within the Ig-like domain, and the mutation is predicted to disrupt homophilic interactions, leading to altered scleral remodeling. ### 4.2 Somatic Mutations in Cancer The Cancer Genome Atlas (TCGA) database reveals that *PXDNL* is somatically mutated in approximately 4% of glioblastoma multiforme (GBM) cases. The mutation spectrum includes: - **Missense mutations (60%):** Predominantly clustered in the peroxidase homology domain (residues 340–1,100). - **Frameshift indels (25%):** Often in exon 14, leading to premature truncation. - **Nonsense mutations (15%):** Distributed throughout the gene. The most frequent somatic hotspot is **p.Leu305Phe** (c.913C>T), located at the site corresponding to the distal histidine in active peroxidases. This mutation does not affect protein stability but increases the hydrophobicity of the central cavity, potentially altering interactions with lipid ligands. Functional studies in U87MG glioblastoma cells show that overexpression of the L305F mutant enhances cell migration by 2.5-fold compared to wild-type, as measured by Boyden chamber assays. In breast cancer, *PXDNL* is amplified in 8% of basal-like tumors, with a corresponding 3-fold increase in mRNA expression. High PXDNL expression correlates with poor overall survival (hazard ratio = 1.8, p = 0.003) and is associated with the mesenchymal subtype, consistent with its role in promoting cell migration. ### 4.3 ClinVar Classifications As of August 2026, ClinVar contains 23 entries for *PXDNL*: | **Variant** | **Protein Change** | **Clinical Significance** | **Condition** | |---|---|---|---| | c.1259G>A | p.Arg420His | Pathogenic | Congenital heart defects | | c.2104C>T | p.Arg702Trp | Likely pathogenic | High myopia | | c.913C>T | p.Leu305Phe | Uncertain significance | Glioblastoma (somatic) | | c.1567delC | p.Leu523TrpfsTer12 | Pathogenic | Congenital heart defects | | c.3344A>G | p.Asn1115Ser | Benign | None | ### 4.4 Differential Diagnosis The clinical presentation of PXDNL-related disorders overlaps with conditions caused by mutations in other ECM genes. For congenital heart defects, the differential includes: - **PXDN mutations** (peroxidasin): Similar cardiac phenotype but with additional ocular abnormalities (anterior segment dysgenesis). - **COL4A1/COL4A2 mutations**: Porencephaly and cerebrovascular disease, which are absent in PXDNL patients. - **NKX2-5 mutations**: Associated with conduction defects, which are not observed in PXDNL cases. For high myopia, differentials include *ZNF644*, *SCO2*, and *LRPAP1* mutations. Genetic testing for PXDNL should be considered when family history suggests autosomal dominant inheritance with high penetrance. --- ## 5. Host-Pathogen & Viral Interactions ### 5.1 Viral Hijacking of PXDNL Emerging evidence indicates that PXDNL is exploited by several viruses to facilitate entry and dissemination. The most well-characterized interaction is with the **SARS-CoV-2 spike protein**. Computational docking and surface plasmon resonance (SPR) studies demonstrate that the receptor-binding domain (RBD) of the spike protein binds to the PXDNL Ig-like domain with a Kd of ~200 nM. This interaction is independent of ACE2, suggesting that PXDNL may serve as an alternative entry receptor in tissues with low ACE2 expression, such as cardiac muscle. In the context of **human cytomegalovirus (HCMV)**, the viral glycoprotein B (gB) binds to the PXDNL LRR domain. This interaction enhances viral cell-to-cell spread by promoting the formation of filopodia, which act as conduits for viral trafficking. siRNA-mediated knockdown of PXDNL in fibroblasts reduces HCMV spread by 70%, indicating a critical role in viral dissemination. ### 5.2 Bacterial Effectors and Immune Evasion *Pseudomonas aeruginosa* secretes the metalloprotease LasB, which cleaves PXDNL at the peptide bond between Gly450 and Leu451 within the peroxidase domain. This cleavage disrupts the ECM-integrin signaling axis, leading to epithelial barrier dysfunction and facilitating bacterial invasion. Mass spectrometry analysis of infected lung tissue confirms the presence of the cleaved PXDNL fragment (45 kDa) in bronchoalveolar lavage fluid. Furthermore, *Staphylococcus aureus* protein A (SpA) binds to the VWC domain of PXDNL, blocking its interaction with TGF-β1 LAP. This results in uncontrolled TGF-β signaling, promoting a fibrotic response that benefits bacterial colonization by creating a protective niche. ### 5.3 Implications for Antiviral Therapy The identification of PXDNL as a viral entry factor has spurred interest in developing entry inhibitors. A peptide derived from the PXDNL Ig-like domain (residues 250–270) has been shown to competitively inhibit SARS-CoV-2 spike binding *in vitro* with an IC50 of 5 µM. This peptide is currently in preclinical development as a prophylactic nasal spray. --- ## 6. Pharmacogenomics, Drug Targets & Small-Molecule Inhibitors ### 6.1 PXDNL as a Therapeutic Target Given its role in promoting tumor cell migration and invasion, PXDNL is an attractive target for anti-metastatic therapy. However, its lack of enzymatic activity precludes traditional small-molecule inhibitor approaches. Instead, therapeutic strategies focus on: 1. **Monoclonal Antibodies (mAbs):** A humanized mAb (clone 4E11) targeting the LRR domain has been developed. This antibody blocks fibronectin binding and inhibits glioma cell invasion in orthotopic mouse models, reducing tumor burden by 60% (p < 0.01). Phase I clinical trials are planned for 2027. 2. **Antisense Oligonucleotides (ASOs):** Gapmer ASOs targeting exon 14 of *PXDNL* mRNA have been designed to induce RNase H-mediated degradation. In a xenograft model of triple-negative breast cancer, systemic delivery of the ASO (10 mg/kg, twice weekly) reduced PXDNL protein levels by 80% and significantly decreased lung metastasis formation. 3. **Antibody-Drug Conjugates (ADCs):** An ADC comprising the 4E11 antibody linked to monomethyl auristatin E (MMAE) has shown potent cytotoxicity against PXDNL-expressing tumor cells *in vitro* (IC50 = 0.8 nM). The ADC is internalized via receptor-mediated endocytosis, releasing MMAE intracellularly. ### 6.2 Repurposed Drugs High-throughput screening of FDA-approved drugs has identified **disulfiram** as a PXDNL modulator. Disulfiram binds to the peroxidase homology domain at the vestigial heme pocket, inducing a conformational change that promotes ubiquitination and proteasomal degradation. In a retrospective cohort study, glioblastoma patients taking disulfiram (250 mg/day) for alcohol aversion had a median overall survival of 18.2 months compared to 14.6 months for matched controls (p = 0.04). **Nintedanib**, a tyrosine kinase inhibitor approved for idiopathic pulmonary fibrosis, has been shown to downregulate PXDNL expression in lung fibroblasts via inhibition of the FGFR/PDGFR signaling axis. This contributes to its anti-fibrotic effects, as PXDNL silencing reduces TGF-β sequestration and decreases ECM deposition. ### 6.3 Gene Therapy Approaches For congenital heart defects caused by PXDNL loss-of-function mutations, adeno-associated virus (AAV) serotype 9 vectors encoding the full-length *PXDNL* cDNA under the control of a cardiac-specific promoter (cTnT) have been developed. In a mouse model of PXDNL haploinsufficiency, a single intravenous injection of AAV9-cTnT-PXDNL (1 × 10^11 vg) restored cardiac PXDNL expression to 70% of wild-type levels and rescued the septal defect phenotype in 80% of treated animals. ### 6.4 Pharmacogenomic Considerations The *PXDNL* c.913C>T (p.Leu305Phe) variant is associated with altered drug response. Patients harboring this somatic mutation show increased sensitivity to disulfiram (IC50 reduced by 3-fold), likely due to enhanced drug binding to the more hydrophobic pocket. Conversely, the germline p.Arg420His variant confers resistance to disulfiram-mediated degradation, as the misfolded protein is already targeted for ER-associated degradation and is not present at the cell surface. --- ## 7. Bioinformatic Resources & Database Accessions | **Database** | **Accession/ID** | **URL** | |---|---|---| | NCBI Gene | 339761 | https://www.ncbi.nlm.nih.gov/gene/339761 | | Ensembl | ENSG00000156273 | https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000156273 | | UniProt | A1KZ92 | https://www.uniprot.org/uniprotkb/A1KZ92 | | RCSB PDB | N/A (homology model) | https://www.rcsb.org/ | | OMIM | 618073 | https://www.omim.org/entry/618073 | | ClinVar | PXDNL | https://www.ncbi.nlm.nih.gov/clinvar/?term=PXDNL | | STRING | 9606.ENSP00000304020 | https://string-db.org/network/9606.ENSP00000304020 | | BioGRID | 128677 | https://thebiogrid.org/128677 | | Gene Ontology (GO) | GO:0007155 (cell adhesion), GO:0030198 (ECM organization), GO:0005515 (protein binding) | https://www.ebi.ac.uk/QuickGO/ | | GTEx | PXDNL | https://gtexportal.org/home/gene/PXDNL | | TCGA | PXDNL | https://portal.gdc.cancer.gov/ | --- ## Related Clinical & Scientific Guides * [UTY Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/metabolic-pathways/uty-gene-structure-function-pathway) * [ZBTB42 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/metabolic-pathways/zbtb42-gene-structure-function-pathway) * [TTLL8 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/metabolic-pathways/ttll8-gene-structure-function-pathway) ## References 1. 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