AIM2

Interferon-inducible protein AIM2 also known as absent in melanoma 2 or simply AIM2 is a protein that in humans is encoded by the AIM2 gene.[5][6] Recent research has shown that AIM2 is part of the inflammasome and contributes to the defence against bacterial and viral DNA.[7]

AIM2
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 3RN2, 3RN5, 3VD8, 4O7Q
Identifiers
Aliases	AIM2, PYHIN4, absent in melanoma 2
External IDs	OMIM: 604578 MGI: 2686159 HomoloGene: 83226 GeneCards: AIM2
Gene location (Human) Chr. Chromosome 1 (human)[1] Band 1q23.1-q23.2 Start 159,062,484 bp[1] End 159,147,096 bp[1]
Gene location (Mouse) Chr. Chromosome 1 (mouse)[2] Band 1|1 H3 Start 173,350,879 bp[2] End 173,466,040 bp[2]
RNA expression pattern More reference expression data
Gene ontology Molecular function • DNA binding • GO:0001948 protein binding • identical protein binding • double-stranded DNA binding Cellular component • cytoplasm • AIM2 inflammasome complex • cell nucleus • nucleoplasm • mitochondrion • cytosol Biological process • positive regulation of cysteine-type endopeptidase activity • pyroptosis • cellular response to interferon-beta • immune system process • tumor necrosis factor-mediated signaling pathway • cellular response to drug • interleukin-1 beta secretion • positive regulation of NF-kappaB transcription factor activity • positive regulation of interleukin-1 beta secretion • immune response • positive regulation of interleukin-1 beta production • positive regulation of protein oligomerization • activation of innate immune response • inflammatory response • negative regulation of NF-kappaB transcription factor activity • positive regulation of defense response to virus by host • apoptotic process • innate immune system Sources:Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	9447	383619
Ensembl	ENSG00000163568	ENSMUSG00000037860
UniProt	O14862	Q91VJ1
RefSeq (mRNA)	NM_004833 NM_001348247	NM_001013779
RefSeq (protein)	NP_004824 NP_001335176	NP_001013801
Location (UCSC)	Chr 1: 159.06 – 159.15 Mb	Chr 1: 173.35 – 173.47 Mb
PubMed search	[3]	[4]
Wikidata
View/Edit Human View/Edit Mouse

Structure

AIM2 is a 343 amino acid protein with a N-terminal DAPIN (or pyrin) domain (amino acids 1-87) and a C-terminal HIN-200 domain (amino acids 138-337), which is known to have two oligonucleotide-binding folds.[8]

Function

AIM2 is a member of the Ifi202/IFI16 family. It plays a putative role in tumorigenic reversion and may control cell proliferation. Interferon-gamma induces expression of AIM2.[6]

Though there has been virtually no biochemistry performed, a model based on cell-based or in vivo experiments has led to the current model of how AIM2 triggers the inflammasome. The C-terminal HIN domain binds double stranded DNA (either viral, bacterial, or even host) and acts as a cytosolic dsDNA sensor. This leads to the oligomerization of the inflammasome complex. The N-terminal pyrin domain of AIM2 interacts with the pyrin domain of another protein ASC (or Apoptosis-associated Speck-like protein containing a caspase activation and recruitment domain). ASC also contains a CARD domain (caspase activation and recruitment domain), that recruits procaspase-1 to the complex. This leads to the autoactivation of caspase-1, an enzyme that processes proinflammatory cytokines (IL-1b and IL-18).[7] AIM2 inflammasome is activated by pharmacological disruption of nuclear envelope integrity.[9]

Clinical relevance

Elevated levels of AIM2 expression are found in skin cells from people with psoriasis.[10] In systemic lupus erythematosus, lysosome dysfunction allows DNA to gain access to the cytosol and activate AIM2 resulting in increased type 1 interferon production.[11]

References

1. GRCh38: Ensembl release 89: ENSG00000163568 - Ensembl, May 2017
2. GRCm38: Ensembl release 89: ENSMUSG00000037860 - Ensembl, May 2017
3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
5. DeYoung KL, Ray ME, Su YA, Anzick SL, Johnstone RW, Trapani JA, Meltzer PS, Trent JM (Aug 1997). "Cloning a novel member of the human interferon-inducible gene family associated with control of tumorigenicity in a model of human melanoma". Oncogene. 15 (4): 453–7. doi:10.1038/sj.onc.1201206. PMID 9242382.
6. "Entrez Gene: AIM2 absent in melanoma 2".
7. Schroder K, Tschopp J (March 2010). "The inflammasomes". Cell. 140 (6): 821–32. doi:10.1016/j.cell.2010.01.040. PMID 20303873.
8. Fernandes-Alnemri T, Yu JW, Datta P, Wu J, Alnemri ES (March 2009). "AIM2 activates the inflammasome and cell death in response to cytoplasmic DNA". Nature. 458 (7237): 509–13. doi:10.1038/nature07710. PMC 2862225. PMID 19158676.
9. Di Micco A, Frera G, Lugrin J, Jamilloux Y, Hsu ET, Tardivel A, De Gassart A, Zaffalon L, Bujisic B, Siegert S, Quadroni M, Broz P, Henry T, Hrycyna CA, Martinon F (August 2016). "AIM2 inflammasome is activated by pharmacological disruption of nuclear envelope integrity". Proceedings of the National Academy of Sciences of the United States of America. 113 (32): E4671-80. doi:10.1073/pnas.1602419113. PMC 4987819. PMID 27462105.
10. Dombrowski Y, Peric M, Koglin S, Kammerbauer C, Göss C, Anz D, Simanski M, Gläser R, Harder J, Hornung V, Gallo RL, Ruzicka T, Besch R, Schauber J (May 2011). "Cytosolic DNA triggers inflammasome activation in keratinocytes in psoriatic lesions". Science Translational Medicine. 3 (82): 82ra38. doi:10.1126/scitranslmed.3002001. PMC 3235683. PMID 21562230.
11. Monteith AJ, Kang S, Scott E, Hillman K, Rajfur Z, Jacobson K, Costello MJ, Vilen BJ (April 2016). "Defects in lysosomal maturation facilitate the activation of innate sensors in systemic lupus erythematosus". Proceedings of the National Academy of Sciences of the United States of America. 113 (15): E2142-51. doi:10.1073/pnas.1513943113. PMC 4839468. PMID 27035940.

External links

• Human AIM2 genome location and AIM2 gene details page in the UCSC Genome Browser.

Further reading

• Landolfo S, Gariglio M, Gribaudo G, Lembo D (1999). "The Ifi 200 genes: an emerging family of IFN-inducible genes". Biochimie. 80 (8–9): 721–8. doi:10.1016/S0300-9084(99)80025-X. PMID 9865494.
• Woerner SM, Kloor M, Schwitalle Y, Youmans H, von Knebel Doeberitz M, Gebert J, Dihlmann S (2007). "The putative tumor suppressor AIM2 is frequently affected by different genetic alterations in microsatellite unstable colon cancers". Genes Chromosomes Cancer. 46 (12): 1080–9. doi:10.1002/gcc.20493. PMID 17726700.
• Chen IF, Ou-Yang F, Hung JY, Liu JC, Wang H, Wang SC, Hou MF, Hortobagyi GN, Hung MC (2006). "AIM2 suppresses human breast cancer cell proliferation in vitro and mammary tumor growth in a mouse model". Mol. Cancer Ther. 5 (1): 1–7. doi:10.1158/1535-7163.MCT-05-0310. PMID 16432157.
• Cresswell KS, Clarke CJ, Jackson JT, Darcy PK, Trapani JA, Johnstone RW (2005). "Biochemical and growth regulatory activities of the HIN-200 family member and putative tumor suppressor protein, AIM2". Biochem. Biophys. Res. Commun. 326 (2): 417–24. doi:10.1016/j.bbrc.2004.11.048. PMID 15582594.
• Liu G, Yu JS, Zeng G, Yin D, Xie D, Black KL, Ying H (2004). "AIM-2: a novel tumor antigen is expressed and presented by human glioma cells". J. Immunother. 27 (3): 220–6. doi:10.1097/00002371-200405000-00006. PMID 15076139.
• Choubey D, Walter S, Geng Y, Xin H (2000). "Cytoplasmic localization of the interferon-inducible protein that is encoded by the AIM2 (absent in melanoma) gene from the 200-gene family". FEBS Lett. 474 (1): 38–42. doi:10.1016/S0014-5793(00)01571-4. PMID 10828447.