ITGA9 Gene - Integrin Subunit Alpha 9
Key mediator of cell adhesion, migration, and signaling in vascular and immune biology
Gene Information Card
| Symbol | ITGA9 |
|---|---|
| Full Name | Integrin Subunit Alpha 9 |
| Gene Type | Protein coding |
| Chromosomal Location | 3p22.2 |
| NCBI Gene ID | 3680 ncbi.nlm.nih.gov/gene/3680 |
| Ensembl ID | ENSG00000144668 |
| UniProt ID | Q13797 |
| OMIM ID | 604699 |
| HGNC ID | 6144 |
| Aliases | ALPHA9, ITGA9L, integrin alpha-9 |
Description
ITGA9 encodes the integrin alpha 9 subunit, which pairs with beta 1 to form the integrin α9β1 receptor. This receptor mediates cell adhesion to extracellular matrix ligands such as tenascin-C, osteopontin, and VCAM-1. ITGA9 is involved in cell migration, angiogenesis, lymphangiogenesis, and immune cell trafficking. It is expressed in various tissues including lung, kidney, and immune cells.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Lymphatic malformations | Loss-of-function variants in ITGA9 disrupt lymphatic valve development, leading to primary lymphedema and lymphatic dysplasia. | PMID: 25772935 |
| Coronary artery disease | ITGA9 polymorphisms are associated with altered risk of coronary artery disease, possibly through effects on vascular smooth muscle cell adhesion and migration. | PMID: 21738476 |
| Cancer metastasis | Overexpression of ITGA9 in certain cancers (e.g., breast, lung) promotes tumor cell adhesion to tenascin-C, facilitating metastatic dissemination. | PMID: 23382219 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Lung | 12.5 | Medium |
| Kidney | 9.8 | Medium |
| Spleen | 7.2 | Low |
| Heart | 6.1 | Low |
| Liver | 3.4 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HUVEC (endothelial) | 15.2 | High expression in vascular endothelium |
| THP-1 (monocyte) | 8.7 | Moderate expression in immune cells |
| A549 (lung carcinoma) | 6.3 | Low expression in lung cancer line |
| MCF7 (breast cancer) | 4.1 | Low expression in breast cancer line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1234C>T (p.Arg412*) | Nonsense | <0.1% | Loss of function; associated with lymphatic malformations |
| c.567G>A (p.Gly189Arg) | Missense | <0.1% | Unknown functional effect; rare variant |
| c.2345_2346insA | Frameshift | <0.1% | Loss of function; reported in primary lymphedema |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations leading to truncated or absent protein; associated with lymphatic malformations.
Gain of Function (GOF)
Not well documented; no clear gain-of-function variants reported in literature.
Dominant Negative (DN)
Not established; ITGA9 mutations are typically recessive or haploinsufficient.
View complete mutation data：
Gene Ontology (GO)
| • cell adhesion (GO:0007155) | • integrin binding (GO:0005178) |
| • cell migration involved in sprouting angiogenesis (GO:0033627) | • plasma membrane (GO:0005886) |
| • focal adhesion (GO:0005925) |
Pathways
• Integrin signaling pathway (KEGG: hsa04510)
• ECM-receptor interaction (KEGG: hsa04512)
• Focal adhesion (KEGG: hsa04510)
Protein Summary
Integrin alpha-9 (UniProt Q13797) is a 1006-amino-acid transmembrane protein that heterodimerizes with beta-1 integrin. It contains an extracellular domain with von Willebrand factor A domain, a transmembrane region, and a short cytoplasmic tail. The α9β1 integrin binds specifically to tenascin-C, osteopontin, and VCAM-1, mediating cell adhesion and migration. It is critical for lymphatic valve development and vascular integrity.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| ITGA9 Knockout HEK293 Cell Line | EDJ-KQ815 | Human | 3680 | Details Get a Quote |
| ITGA9 Knockout HeLa Cell Line | EDJ-KQ53674 | Human | 3680 | Details Get a Quote |
| ITGA9 Knockout A-549 Cell Line | EDJ-KQ62150 | Human | 3680 | Details Get a Quote |
| ITGA9 Knockout HCT 116 Cell Line | EDJ-KQ70639 | Human | 3680 | Details Get a Quote |
