| Name | coagulation factor VIII-associated 2 |
| Description | This gene is part of a region that is repeated three times on chromosome X, once in intron 22 of the F8 gene and twice closer to the Xq telomere. This record represents the middle copy. Although its function is unknown, the observation that this gene is conserved in the mouse implies it has some function. Unlike factor VIII, this gene is transcribed abundantly in a wide variety of cell types. [provided by RefSeq, Jul 2008] |
| Summary |
{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n F8A2 is one of the three human F8A genes that encode the huntingtin‐associated protein 40 (HAP40), a conserved and abundant partner of the huntingtin (HTT) protein. Structural and biochemical studies have demonstrated that HAP40 binds tightly to HTT, stabilizing its solenoid‐like, predominantly α‐helical conformation by engaging with multiple HEAT‐repeat domains and a bridging domain in HTT."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " In this complex, HAP40 acts as an essential “molecular glue” that not only preserves the overall structure of HTT but also modulates its interactions with other cellular partners involved in intracellular trafficking and vesicular transport. HAP40’s stabilizing effect on HTT is mirrored by its dramatically increased cellular half‐life when in complex with the HTT protein"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": ", and changes in HAP40 levels have been associated with disease phenotypes in Huntington’s disease. In affected cells, overexpression of HAP40 has been linked to enhanced accumulation of mutant HTT aggregates and impaired proteasome function, indicating its potential role in proteostasis and pathogenic protein interactions."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "4"}]}, {"type": "t", "text": " Moreover, detailed biophysical studies have shown that even in the presence of pathogenic polyglutamine expansions in HTT, the global conformation of the HTT–HAP40 complex remains largely unaltered"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "5"}]}, {"type": "t", "text": ", suggesting that HAP40 may be critical for maintaining a “ready‐to‐function” state of HTT. Intriguingly, immunohistochemical investigations have also identified HAP40 within specific intranuclear structures—rodlets that display a unique biochemical composition—hinting at additional, yet to be fully elucidated, roles in nuclear organization or protein sequestration."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "6"}]}, {"type": "t", "text": "\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Qiang Guo, Bin Huang, Jingdong Cheng, et al. "}, {"type": "b", "children": [{"type": "t", "text": "The cryo-electron microscopy structure of huntingtin."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Nature (2018)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/nature25502"}], "href": "https://doi.org/10.1038/nature25502"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "29466333"}], "href": "https://pubmed.ncbi.nlm.nih.gov/29466333"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Rachel J Harding, Justin C Deme, Johannes F Hevler, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Huntingtin structure is orchestrated by HAP40 and shows a polyglutamine expansion-specific interaction with exon 1."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Commun Biol (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/s42003-021-02895-4"}], "href": "https://doi.org/10.1038/s42003-021-02895-4"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "34880419"}], "href": "https://pubmed.ncbi.nlm.nih.gov/34880419"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Bin Huang, Manuel Seefelder, Eva Buck, et al. "}, {"type": "b", "children": [{"type": "t", "text": "HAP40 protein levels are huntingtin-dependent and decrease in Huntington disease."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Neurobiol Dis (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.nbd.2021.105476"}], "href": "https://doi.org/10.1016/j.nbd.2021.105476"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "34390835"}], "href": "https://pubmed.ncbi.nlm.nih.gov/34390835"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Zih-Ning Huang, Lu-Shiun Her "}, {"type": "b", "children": [{"type": "t", "text": "The Ubiquitin Receptor ADRM1 Modulates HAP40-Induced Proteasome Activity."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Mol Neurobiol (2017)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1007/s12035-016-0247-y"}], "href": "https://doi.org/10.1007/s12035-016-0247-y"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "27815841"}], "href": "https://pubmed.ncbi.nlm.nih.gov/27815841"}]}, {"type": "r", "ref": 5, "children": [{"type": "t", "text": "Bin Huang, Qiang Guo, Marie L Niedermeier, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Pathological polyQ expansion does not alter the conformation of the Huntingtin-HAP40 complex."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Structure (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.str.2021.04.003"}], "href": "https://doi.org/10.1016/j.str.2021.04.003"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "33909994"}], "href": "https://pubmed.ncbi.nlm.nih.gov/33909994"}]}, {"type": "r", "ref": 6, "children": [{"type": "t", "text": "Pavel Milman, John Woulfe "}, {"type": "b", "children": [{"type": "t", "text": "Novel variant of neuronal intranuclear rodlet immunoreactive for 40 kDa huntingtin associated protein and ubiquitin in the mouse brain."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Comp Neurol (2013)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/cne.23381"}], "href": "https://doi.org/10.1002/cne.23381"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "23749422"}], "href": "https://pubmed.ncbi.nlm.nih.gov/23749422"}]}]}]}
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| NCBI Gene ID | 474383 |
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F8A2 has 1,273 functional associations with biological entities spanning 7 categories (molecular profile, chemical, functional term, phrase or reference, disease, phenotype or trait, structural feature, cell line, cell type or tissue, gene, protein or microRNA) extracted from 43 datasets.
Click the + buttons to view associations for F8A2 from the datasets below.
If available, associations are ranked by standardized value
| Dataset | Summary | |
|---|---|---|
| Allen Brain Atlas Aging Dementia and Traumatic Brain Injury Tissue Sample Gene Expression Profiles | tissue samples with high or low expression of F8A2 gene relative to other tissue samples from the Allen Brain Atlas Aging Dementia and Traumatic Brain Injury Tissue Sample Gene Expression Profiles dataset. | |
| Carcinogenome Chemical Perturbation Carcinogenicity Signatures | small molecule perturbations changing expression of F8A2 gene from the Carcinogenome Chemical Perturbation Carcinogenicity Signatures dataset. | |
| ChEA Transcription Factor Binding Site Profiles | transcription factor binding site profiles with transcription factor binding evidence at the promoter of F8A2 gene from the CHEA Transcription Factor Binding Site Profiles dataset. | |
| ChEA Transcription Factor Targets | transcription factors binding the promoter of F8A2 gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets dataset. | |
| ChEA Transcription Factor Targets 2022 | transcription factors binding the promoter of F8A2 gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets 2022 dataset. | |
| CM4AI KOLF21J CRISPRi Gene Perturbation Atlas | gene perturbations changing expression of F8A2 gene from the CM4AI KOLF21J CRISPRi Gene Perturbation Atlas dataset. | |
| COMPARTMENTS Curated Protein Localization Evidence Scores | cellular components containing F8A2 protein from the COMPARTMENTS Curated Protein Localization Evidence Scores dataset. | |
| COMPARTMENTS Curated Protein Localization Evidence Scores 2025 | cellular components containing F8A2 protein from the COMPARTMENTS Curated Protein Localization Evidence Scores 2025 dataset. | |
| COMPARTMENTS Text-mining Protein Localization Evidence Scores | cellular components co-occuring with F8A2 protein in abstracts of biomedical publications from the COMPARTMENTS Text-mining Protein Localization Evidence Scores dataset. | |
| COMPARTMENTS Text-mining Protein Localization Evidence Scores 2025 | cellular components co-occuring with F8A2 protein in abstracts of biomedical publications from the COMPARTMENTS Text-mining Protein Localization Evidence Scores 2025 dataset. | |
| DISEASES Text-mining Gene-Disease Association Evidence Scores | diseases co-occuring with F8A2 gene in abstracts of biomedical publications from the DISEASES Text-mining Gene-Disease Assocation Evidence Scores dataset. | |
| DISEASES Text-mining Gene-Disease Association Evidence Scores 2025 | diseases co-occuring with F8A2 gene in abstracts of biomedical publications from the DISEASES Text-mining Gene-Disease Assocation Evidence Scores 2025 dataset. | |
| DisGeNET Gene-Disease Associations | diseases associated with F8A2 gene in GWAS and other genetic association datasets from the DisGeNET Gene-Disease Associations dataset. | |
| ENCODE Histone Modification Site Profiles | histone modification site profiles with high histone modification abundance at F8A2 gene from the ENCODE Histone Modification Site Profiles dataset. | |
| ENCODE Transcription Factor Binding Site Profiles | transcription factor binding site profiles with transcription factor binding evidence at the promoter of F8A2 gene from the ENCODE Transcription Factor Binding Site Profiles dataset. | |
| ENCODE Transcription Factor Targets | transcription factors binding the promoter of F8A2 gene in ChIP-seq datasets from the ENCODE Transcription Factor Targets dataset. | |
| ESCAPE Omics Signatures of Genes and Proteins for Stem Cells | PubMedIDs of publications reporting gene signatures containing F8A2 from the ESCAPE Omics Signatures of Genes and Proteins for Stem Cells dataset. | |
| GTEx Tissue Gene Expression Profiles 2023 | tissues with high or low expression of F8A2 gene relative to other tissues from the GTEx Tissue Gene Expression Profiles 2023 dataset. | |
| HPA Cell Line Gene Expression Profiles | cell lines with high or low expression of F8A2 gene relative to other cell lines from the HPA Cell Line Gene Expression Profiles dataset. | |
| HPA Tissue Gene Expression Profiles | tissues with high or low expression of F8A2 gene relative to other tissues from the HPA Tissue Gene Expression Profiles dataset. | |
| HPA Tissue Sample Gene Expression Profiles | tissue samples with high or low expression of F8A2 gene relative to other tissue samples from the HPA Tissue Sample Gene Expression Profiles dataset. | |
| HPM Cell Type and Tissue Protein Expression Profiles | cell types and tissues with high or low expression of F8A2 protein relative to other cell types and tissues from the HPM Cell Type and Tissue Protein Expression Profiles dataset. | |
| InterPro Predicted Protein Domain Annotations | protein domains predicted for F8A2 protein from the InterPro Predicted Protein Domain Annotations dataset. | |
| JASPAR Predicted Human Transcription Factor Targets 2025 | transcription factors regulating expression of F8A2 gene predicted using known transcription factor binding site motifs from the JASPAR Predicted Human Transcription Factor Targets dataset. | |
| JASPAR Predicted Transcription Factor Targets | transcription factors regulating expression of F8A2 gene predicted using known transcription factor binding site motifs from the JASPAR Predicted Transcription Factor Targets dataset. | |
| Klijn et al., Nat. Biotechnol., 2015 Cell Line Gene CNV Profiles | cell lines with high or low copy number of F8A2 gene relative to other cell lines from the Klijn et al., Nat. Biotechnol., 2015 Cell Line Gene CNV Profiles dataset. | |
| KnockTF Gene Expression Profiles with Transcription Factor Perturbations | transcription factor perturbations changing expression of F8A2 gene from the KnockTF Gene Expression Profiles with Transcription Factor Perturbations dataset. | |
| LOCATE Predicted Protein Localization Annotations | cellular components predicted to contain F8A2 protein from the LOCATE Predicted Protein Localization Annotations dataset. | |
| NIBR DRUG-seq U2OS MoA Box Gene Expression Profiles | drug perturbations changing expression of F8A2 gene from the NIBR DRUG-seq U2OS MoA Box dataset. | |
| NURSA Protein Complexes | protein complexs containing F8A2 protein recovered by IP-MS from the NURSA Protein Complexes dataset. | |
| PFOCR Pathway Figure Associations 2023 | pathways involving F8A2 protein from the PFOCR Pathway Figure Associations 2023 dataset. | |
| PFOCR Pathway Figure Associations 2024 | pathways involving F8A2 protein from the Wikipathways PFOCR 2024 dataset. | |
| Roadmap Epigenomics Cell and Tissue Gene Expression Profiles | cell types and tissues with high or low expression of F8A2 gene relative to other cell types and tissues from the Roadmap Epigenomics Cell and Tissue Gene Expression Profiles dataset. | |
| Roadmap Epigenomics Histone Modification Site Profiles | histone modification site profiles with high histone modification abundance at F8A2 gene from the Roadmap Epigenomics Histone Modification Site Profiles dataset. | |
| Rummagene Transcription Factor Associations 2026 | transcription factors regulating expression of F8A2 gene from the Rummagene Transcription Factor Associations 2026 dataset. | |
| RummaGEO Drug Perturbation Signatures | drug perturbations changing expression of F8A2 gene from the RummaGEO Drug Perturbation Signatures dataset. | |
| RummaGEO Gene Perturbation Signatures | gene perturbations changing expression of F8A2 gene from the RummaGEO Gene Perturbation Signatures dataset. | |
| TISSUES Curated Tissue Protein Expression Evidence Scores | tissues with high expression of F8A2 protein from the TISSUES Curated Tissue Protein Expression Evidence Scores dataset. | |
| TISSUES Curated Tissue Protein Expression Evidence Scores 2025 | tissues with high expression of F8A2 protein from the TISSUES Curated Tissue Protein Expression Evidence Scores 2025 dataset. | |
| TISSUES Experimental Tissue Protein Expression Evidence Scores | tissues with high expression of F8A2 protein in proteomics datasets from the TISSUES Experimental Tissue Protein Expression Evidence Scores dataset. | |
| TISSUES Text-mining Tissue Protein Expression Evidence Scores | tissues co-occuring with F8A2 protein in abstracts of biomedical publications from the TISSUES Text-mining Tissue Protein Expression Evidence Scores dataset. | |
| TISSUES Text-mining Tissue Protein Expression Evidence Scores 2025 | tissues co-occuring with F8A2 protein in abstracts of biomedical publications from the TISSUES Text-mining Tissue Protein Expression Evidence Scores 2025 dataset. | |
| WikiPathways Pathways 2014 | pathways involving F8A2 protein from the Wikipathways Pathways 2014 dataset. | |
