Skip to main content

Pyrin

Developmental stage

First detected in bone marrow promyelocytes. Expression increases throughout myelocyte differentiation and peaks in the mature myelomonocytic cells.

Domain

The B box-type zinc finger interacts, possibly intramolecularly, with the pyrin domain; this may be an autoinhibitory mechanism released by PSTPIP1 binding.

Function

Involved in the regulation of innate immunity and the inflammatory response in response to IFNG/IFN-gamma. Organizes autophagic machinery by serving as a platform for the assembly of ULK1, Beclin 1/BECN1, ATG16L1, and ATG8 family members and recognizes specific autophagy targets, thus coordinating target recognition with assembly of the autophagic apparatus and initiation of autophagy. Acts as an autophagy receptor for the degradation of several inflammasome components, including CASP1, NLRP1 and NLRP3, hence preventing excessive IL1B- and IL18-mediated inflammation (PubMed:16785446, PubMed:17431422, PubMed:26347139). However, it can also have a positive effect in the inflammatory pathway, acting as an innate immune sensor that triggers PYCARD/ASC specks formation, caspase-1 activation, and IL1B and IL18 production (PubMed:16037825, PubMed:27030597, PubMed:28835462). It is required for PSTPIP1-induced PYCARD/ASC oligomerization and inflammasome formation. Recruits PSTPIP1 to inflammasomes, and is required for PSTPIP1 oligomerization (PubMed:10807793, PubMed:11468188, PubMed:17964261, PubMed:18577712, PubMed:19109554, PubMed:19584923).

Involvement in disease

Familial Mediterranean fever, autosomal recessive

ARFMF

A hereditary periodic fever syndrome characterized by recurrent episodic fever, serosal inflammation and pain in the abdomen, chest or joints. It is frequently complicated by reactive amyloidosis, which leads to renal failure and can be prophylactically treated with colchicine.

None

The disease is caused by variants affecting the gene represented in this entry. The disease-associated mutations in the B30.2/SPRY domain perturb ULK1 recruitment and autophagic degradation of inflammasome components, including NLRP3, and hence may contribute to the inflammatory phenotype associated with ARFMF.

Familial Mediterranean fever, autosomal dominant

ADFMF

A hereditary periodic fever syndrome characterized by periodic fever, serosal inflammation and pain in the abdomen, chest or joints as seen also in the autosomal recessive form of the disease. It is associated with reactive renal amyloidosis and characterized by colchicine unresponsiveness.

None

The disease is caused by variants affecting the gene represented in this entry.

Pyrin-associated autoinflammatory disease

PAAND

An autosomal dominant autoinflammatory disorder characterized by childhood onset of recurrent episodes of fever, neutrophilic dermatosis, myalgia and arthralgia. The neutrophilic dermatosis comprises a spectrum of clinical manifestations, including severe acne, sterile skin abscesses, pyoderma gangrenosum, and neutrophilic small-vessel vasculitis. Pathological examination of affected skin shows a dense, predominantly neutrophilic, vascular, perivascular, and interstitial infiltrate. PAAND has incomplete penetrance and variable expressivity.

None

The disease is caused by variants affecting the gene represented in this entry.

Post-translational modifications

Cleaved by CASP1 (Probable). The N-terminal cleavage product localizes to the nucleus as a filamentous network and to the cytoplasm, interacts more strongly with RELA and NFKBIA than the full-length protein, enhances the nuclear localization of RELA and induces NFKBIA proteolysis. The C-terminal cleavage product localizes to the cytoplasm.

Phosphorylation at Ser-242 is required for the interaction with 14-3-3 proteins and down-regulation of pyrin proinflammatory activity.

Tissue specificity

Expressed in peripheral blood leukocytes, particularly in mature granulocytes and to a lesser extent in monocytes but not in lymphocytes. Detected in spleen, lung and muscle, probably as a result of leukocyte infiltration in these tissues. Not expressed in thymus, prostate, testis, ovary, small intestine, colon, heart, brain, placenta, liver, kidney, pancreas. Expression detected in several myeloid leukemic, colon cancer, and prostate cancer cell lines.

Cellular localization

  • Isoform 1
  • Cytoplasm
  • Cytoskeleton
  • Cell projection
  • Ruffle
  • Cell projection
  • Lamellipodium
  • Nucleus
  • Cytoplasm
  • Cytoplasmic vesicle
  • Autophagosome
  • Associated with microtubules and with the filamentous actin of perinuclear filaments and peripheral lamellar ruffles. In pre-apoptotic cells, colocalizes with PYCARD/ASC in large specks (inflammasomes). In migrating monocytes, strongly polarized at the leading edge of the cell where it colocalizes with polymerizing actin and PYCARD/ASC.
  • Isoform 2
  • Nucleus

Alternative names

  • Pyrin
  • Marenostrin
  • TRIM20
  • MEFV
  • MEF

Target type

Proteins

Molecular weight

86444Da