DNAI3 Gene: Dynein Axonemal Intermediate Chain 3
Essential Component of Ciliary and Flagellar Motility
Gene Information Card
| Symbol | DNAI3 |
|---|---|
| Full Name | dynein axonemal intermediate chain 3 |
| Gene Type | protein-coding |
| Chromosomal Location | 1p13.3 |
| NCBI Gene ID | 64421 ncbi.nlm.nih.gov/gene/64421 |
| Ensembl ID | ENSG00000117650 |
| UniProt ID | Q9Y6N9 |
| OMIM ID | 610048 |
| HGNC ID | 2959 |
| Aliases | DIC3, FLJ20241, MGC138207 |
Description
DNAI3 encodes an intermediate chain component of the axonemal dynein complex, which is essential for ciliary and flagellar motility. This protein is part of the outer dynein arm and is required for proper microtubule sliding and ciliary beat frequency. Mutations in DNAI3 are associated with primary ciliary dyskinesia (PCD), often with situs inversus (Kartagener syndrome).
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Primary Ciliary Dyskinesia (PCD) | Loss-of-function mutations impair outer dynein arm assembly, reducing ciliary motility and mucociliary clearance. | ClinVar, OMIM |
| Kartagener Syndrome | Biallelic DNAI3 mutations cause PCD with situs inversus totalis due to defective nodal cilia during embryogenesis. | OMIM, PubMed |
| Situs Inversus | Dysfunctional nodal cilia disrupt left-right asymmetry determination, leading to mirror-image organ arrangement. | OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 28.5 | High |
| Lung | 12.3 | Medium |
| Trachea | 10.8 | Medium |
| Fallopian Tube | 9.2 | Medium |
| Brain (cerebellum) | 2.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| BEAS-2B (bronchial epithelial) | 15.4 | Ciliated cell line |
| HBE (human bronchial epithelial) | 14.2 | Primary ciliated cells |
| A549 (lung carcinoma) | 1.8 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1345C>T (p.Arg449*) | Nonsense | Rare | Loss of function; truncation of intermediate chain |
| c.2020G>A (p.Gly674Arg) | Missense | Rare | Disrupts dynein arm assembly |
| c.1177_1178del (p.Leu393fs) | Frameshift | Rare | Premature stop; loss of function |
Mutation functional classification
Loss of Function (LOF)
Most DNAI3 mutations are loss-of-function (nonsense, frameshift, splice-site), leading to absent or nonfunctional outer dynein arms.
Gain of Function (GOF)
No gain-of-function mutations reported for DNAI3.
Dominant Negative (DN)
No dominant-negative mutations reported; inheritance is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • axonemal dynein complex (GO:0005858) | • microtubule-based movement (GO:0007018) |
| • cilium movement (GO:0003341) | • dynein complex (GO:0030286) |
| • microtubule (GO:0005874) |
Pathways
• KEGG: hsa05016 (Huntington disease - includes axonemal dynein)
• Reactome: R-HSA-5620920 (Cargo trafficking to the cilium)
• Reactome: R-HSA-5617833 (Cilium assembly)
Protein Summary
DNAI3 encodes a 674-amino-acid intermediate chain protein (UniProt Q9Y6N9) that localizes to the outer dynein arm of ciliary axonemes. It contains WD40 repeats that mediate protein-protein interactions within the dynein complex. The protein is essential for generating the force required for ciliary bending and coordinated beating. Defects in DNAI3 disrupt mucociliary clearance, leading to chronic respiratory infections, bronchiectasis, and infertility.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| DNAI3 Knockout HEK293 Cell Line | EDJ-KQ8975 | Human | 126820 | Details Get a Quote |
| DNAI3 Knockout HCT 116 Cell Line | EDJ-KQ35391 | Human | 126820 | Details Get a Quote |
| DNAI3 Knockout HeLa Cell Line | EDJ-KQ58188 | Human | 126820 | Details Get a Quote |
| DNAI3 Knockout A-549 Cell Line | EDJ-KQ66678 | Human | 126820 | Details Get a Quote |
