MEFV (Mediterranean fever) is a human gene that provides instructions for making a protein called pyrin (also known as marenostrin). Pyrin is produced in certain white blood cells (neutrophils, eosinophils and monocytes) that play a role in inflammation and in fighting infection. Inside these white blood cells, pyrin is found with the cytoskeleton, the structural framework that helps to define the shape, size, and movement of a cell. Pyrin's protein structure also allows it to interact with other molecules involved in fighting infection and in the inflammatory response.

MEFV
Available structures
PDBOrtholog search: PDBe RCSB
Identifiers
AliasesMEFV, FMF, MEF, TRIM20, Mediterranean fever, pyrin innate immunity regulator, MEFV innate immuity regulator, pyrin, PAAND
External IDsOMIM: 608107; MGI: 1859396; HomoloGene: 32441; GeneCards: MEFV; OMA:MEFV - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_001198536
NM_000243

NM_001161790
NM_001161791
NM_019453

RefSeq (protein)

NP_000234
NP_001185465

NP_001155262
NP_001155263
NP_062326

Location (UCSC)Chr 16: 3.24 – 3.26 MbChr 16: 3.53 – 3.54 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Although pyrin's function is not fully understood, it likely assists in keeping the inflammation process under control. Research indicates that pyrin helps regulate inflammation by interacting with the cytoskeleton. Pyrin may direct the migration of white blood cells to sites of inflammation and stop or slow the inflammatory response when it is no longer needed.

The MEFV gene is located on the short (p) arm of chromosome 16 at position 13.3, from base pair 3,292,027 to 3,306,626.[5]

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More than 80 MEFV mutations that cause familial Mediterranean fever have been identified. A few mutations delete small amounts of DNA from the MEFV gene, which can lead to an abnormally small protein. Most MEFV mutations, however, change one of the protein building blocks (amino acids) used to make pyrin. The most common mutation replaces the amino acid methionine with the amino acid valine at protein position 694 (written as Met694Val or M694V). Among people with familial Mediterranean fever, this particular mutation is also associated with an increased risk of developing amyloidosis, a complication in which abnormal protein deposits can lead to kidney failure. Some evidence suggests that another gene, called SAA1, can further modify the risk of developing amyloidosis among people with the M694V mutation.

MEFV mutations lead to reduced amounts of pyrin or a malformed pyrin protein that cannot function properly. As a result, pyrin cannot perform its presumed role in controlling inflammation, leading to an inappropriate or prolonged inflammatory response. Fever and inflammation in the abdomen, chest, joints, or skin are signs of familial Mediterranean fever. Pyrin forms an inflammasome which senses RhoA GTPases inactivation and subsequent kinases (PKN1 and PKN2) inactivation.[6] These kinases phosphorylate two serine residues located in the linker encoded by MEFV exon 2, allowing proteins 14.3.3 to keep pyrin inflammasome in an inactive state. Mutations in these serine residues are responsible for Pyrin-Associated Autoinflammation with Neutrophilic Dermatosis (PAAND).[7] Recently, it has been shown that pyrin dephosphorylation is sufficient to trigger inflammasome activation in familial Mediterranean fever patients.[8] Furthermore, while the trigger of FMF flares remain unknown, steroid hormone catabolites (pregnanolone and etiocholanaolone) have been shown to activate the pyrin inflammasome, in vitro, by interacting with the B30.2 domain (coded by exon 10).[9]

See also

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References

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  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000103313Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000022534Ensembl, 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. ^ "MEFV - Mediterranean fever". US National Library of Medicine, National Institutes of Health, Department of Health & Human Services. 2011-04-07. Retrieved 2011-04-14.
  6. ^ Park YH, Wood G, Kastner DL, Chae JJ (August 2016). "Pyrin inflammasome activation and RhoA signaling in the autoinflammatory diseases FMF and HIDS". Nature Immunology. 17 (8): 914–921. doi:10.1038/ni.3457. PMC 4955684. PMID 27270401.
  7. ^ Moghaddas F, Llamas R, De Nardo D, Martinez-Banaclocha H, Martinez-Garcia JJ, Mesa-Del-Castillo P, et al. (December 2017). "A novel Pyrin-Associated Autoinflammation with Neutrophilic Dermatosis mutation further defines 14-3-3 binding of pyrin and distinction to Familial Mediterranean Fever". Annals of the Rheumatic Diseases. 76 (12): 2085–2094. doi:10.1136/annrheumdis-2017-211473. PMC 5687562. PMID 28835462.
  8. ^ Magnotti F, Lefeuvre L, Benezech S, Malsot T, Waeckel L, Martin A, et al. (November 2019). "Pyrin dephosphorylation is sufficient to trigger inflammasome activation in familial Mediterranean fever patients". EMBO Molecular Medicine. 11 (11): e10547. doi:10.15252/emmm.201910547. PMC 6835204. PMID 31589380.
  9. ^ Magnotti F, Chirita D, Dalmon S, Martin A, Bronnec P, Sousa J, et al. (October 2022). "Steroid hormone catabolites activate the pyrin inflammasome through a non-canonical mechanism". Cell Reports. 41 (2): 111472. bioRxiv 10.1101/2021.10.29.466454. doi:10.1016/j.celrep.2022.111472.
  10. ^ Dogan H, Akdemir F, Tasdemir S, Atis O, Diyarbakir E, Yildirim R, et al. (July 2014). "A novel insertion mutation identified in exon 10 of the MEFV gene associated with Familial Mediterranean Fever". BMC Medical Genetics. 15 (1): 74. doi:10.1186/1471-2350-15-74. PMC 4094690. PMID 24980720.

Further reading

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By: Dr. Rozan Ehab Ahmed