| MDA5 Protein | |
|---|---|
| Gene | IFIH1 |
| UniProt | Q9QZF5 |
| PDB | 3GA6, 4GL2, 5W5V |
| Mol. Weight | 116 kDa |
| Localization | Cytoplasm |
| Family | DEAD-box helicase family |
| Diseases | Alzheimer's Disease, Parkinson's Disease, Aicardi-Goutières Syndrome |
Mda5 Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
MDA5 (Melanoma Differentiation-Associated Protein 5), encoded by IFIH1, is a cytoplasmic pattern recognition receptor that detects viral RNA. It belongs to the DEAD-box helicase family and has a molecular weight of approximately 116 kDa^1. This protein is localized to Cytoplasm and plays a significant role in the pathogenesis of Alzheimer's Disease, Parkinson's Disease, Aicardi-Goutières Syndrome.
The MDA5 protein has been characterized structurally through X-ray crystallography. Available PDB structures include: 3GA6, 4GL2, 5W5V^2.
The protein's three-dimensional structure can also be explored via the AlphaFold Protein Structure Database.
Under physiological conditions, MDA5 performs essential functions in antiviral immunity. It is primarily found in Cytoplasm and contributes to detecting viral RNA and initiating antiviral immune responses.
MDA5 is a cytoplasmic RNA helicase that detects long double-stranded RNA:
MDA5 contains multiple functional domains:
| Feature | MDA5 | RIG-I |
|---|---|---|
| Ligand | Long dsRNA (>1kb) | 5'PPP dsRNA, short dsRNA |
| Viruses | Picornaviruses | Influenza, HCV, VSV |
| Activation | Oligomerization | Conformational change |
MDA5 is implicated in the following conditions:
Dysregulation of MDA5 contributes to neuronal damage through various mechanisms including chronic neuroinflammation, increased interferon response, and glial activation.
MDA5 represents an important therapeutic target. Multiple drug development programs are exploring strategies to modulate its function:
The study of Mda5 Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Andrejeva J, et al. (2004). The V proteins of paramyxoviruses bind the IFN-inducible RNA helicase, MDA5, and inhibit its ability to induce interferon. Nat Immunol. 5(7):730-737. DOI
Mott R, et al. (2016). A structure-function comparison of the RIG-I and MDA5 RNA sensors. J Mol Biol. 428(11):2374-2388. DOI
Kang DC, et al. (2004). MDA-5: An interferon-inducible putative RNA helicase with double-stranded RNA-dependent ATPase activity and melanoma growth-suppressive properties. Proc Natl Acad Sci U S A. 101(7):2123-2128. DOI
Kato H, et al. (2006). Differential roles of MDA5 and RIG-I helicases in the recognition of RNA viruses. Nature. 441(7089):101-105. DOI
Rice GI, et al. (2014). Gain-of-function mutations in IFIH1 cause a spectrum of human disease phenotypes associated with upregulated type I interferon signaling. Nat Genet. 46(5):503-509. DOI