DEFB121: Defensin Beta 121
A beta-defensin gene involved in antimicrobial host defense and potential roles in mucosal immunity.
Gene Information Card
| Symbol | DEFB121 |
|---|---|
| Full Name | Defensin Beta 121 |
| Gene Type | protein-coding |
| Chromosomal Location | 20q11.21 |
| NCBI Gene ID | 245931 ncbi.nlm.nih.gov/gene/245931 |
| Ensembl ID | ENSG00000188312 |
| UniProt ID | Q8N688 |
| OMIM ID | 614156 |
| HGNC ID | 18102 |
| Aliases | DEFB-21, DEFB121, beta-defensin 121 |
Description
DEFB121 (Defensin Beta 121) is a protein-coding gene belonging to the beta-defensin family. Beta-defensins are antimicrobial peptides involved in the innate immune response, particularly at mucosal surfaces. They exhibit broad-spectrum antimicrobial activity against bacteria, fungi, and viruses. DEFB121 is expressed in various epithelial tissues and may play a role in host defense and inflammation.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Chronic Obstructive Pulmonary Disease (COPD) | Altered defensin expression may contribute to airway inflammation and susceptibility to infection. | PMID: 21814540 |
| Cystic Fibrosis | Defensin dysregulation in airway epithelium may affect bacterial clearance. | PMID: 16950829 |
| Inflammatory Bowel Disease | Beta-defensin copy number variation and expression changes are associated with mucosal inflammation. | PMID: 19865100 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 0.6 | Low |
| Skin | 0.3 | Low |
| Lung | 0.2 | Low |
| Prostate | 0.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| A549 (lung carcinoma) | 0.1 | Low expression |
| HaCaT (keratinocyte) | 0.2 | Low expression |
| Caco-2 (colorectal adenocarcinoma) | 0.1 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| rs11362 | SNP | 0.05 (global) | May alter peptide structure; functional impact unknown |
| rs1800972 | SNP | 0.02 (global) | Associated with altered defensin expression in some studies |
Mutation functional classification
Loss of Function (LOF)
No well-characterized loss-of-function mutations reported for DEFB121.
Gain of Function (GOF)
No gain-of-function mutations described.
Dominant Negative (DN)
Not applicable.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Antimicrobial peptides (Reactome: R-HSA-6803157)
• Innate Immune System (Reactome: R-HSA-168249)
Protein Summary
Defensin beta 121 is a small, cationic antimicrobial peptide characterized by a conserved beta-defensin motif containing six cysteine residues that form three disulfide bonds. The mature peptide is secreted and exhibits antimicrobial activity against a range of pathogens. Its expression is primarily in epithelial tissues, suggesting a role in mucosal immunity.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| DEFB121 Knockout HEK293 Cell Line | EDJ-KQ11514 | Human | 245934 | Details Get a Quote |
| DEFB121 Knockout HeLa Cell Line | EDJ-KQ59219 | Human | 245934 | Details Get a Quote |
| DEFB121 Knockout A-549 Cell Line | EDJ-KQ67687 | Human | 245934 | Details Get a Quote |
| DEFB121 Knockout HCT 116 Cell Line | EDJ-KQ76071 | Human | 245934 | Details Get a Quote |
