title: Pyrin and ASC co-localize to cellular sites that are rich in polymerizing actin.
abstract: Familial Mediterranean fever (FMF) is an autoinflammatory disease caused by mutations in the MEFV locus, which encodes the protein pyrin. While it is known that pyrin is expressed in myeloid cells and several fibroblastic cell types, the exact function of pyrin in these cells and the mechanism underlying the pathological effect of pyrin mutations have yet to be revealed. Here, we document that in migrating human monocytes, pyrin protein is dramatically polarized at the leading edge, where it co-localizes with polymerizing actin. ASC (Apoptosis-associated Speck protein with CARD domain), a known pyrin-interacting protein and a critical component of the inflamma-some, is also located at the leading edge in migrating monocytes. Similarly, both pyrin and ASC concentrate in dynamically polymerizing actin-rich tails generated by Listeria monocytogenes. Pyrin's B-box and coiled-coil region is required for its association with Listeria tails. Pyrin also binds, with low affinity and via the same domains, to actin, VASP, and Arp3. Though disease-causing mutations in pyrin do not appear to alter its localization to the leading edge or to Listeria rocket tails, they could potentially have important functional consequences in the context of processes such as migration and cell synapse formation. The co-localization of pyrin and ASC together at such sites may provide an important link between cytoskeletal signaling and inflammasome function.
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, Box 2200, Ann Arbor, MI 48109-2200, USA.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Waite
authors.forename: Philip
authors.initials: P
authors.lastname: Schaner
authors.forename: Chunbo
authors.initials: C
authors.lastname: Hu
authors.forename: Neil
authors.initials: N
authors.lastname: Richards
authors.forename: Banu
authors.initials: B
authors.lastname: Balci-Peynircioglu
authors.forename: Arthur
authors.initials: A
authors.lastname: Hong
authors.forename: Michelle
authors.initials: M
authors.lastname: Fox
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Gumucio
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis; D053468:CARD Signaling Adaptor Proteins; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D003598:Cytoskeletal Proteins / Q000502:physiology*; D010505:Familial Mediterranean Fever / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007249:Inflammation / Q000235:genetics / Q000503:physiopathology; D008089:Listeria monocytogenes / Q000472:pathogenicity; D009000:Monocytes / Q000502:physiology*; D010957:Plasmids; D000071198:Pyrin
chemical_list: D000199:Actins; D053468:CARD Signaling Adaptor Proteins; D003598:Cytoskeletal Proteins; C000604192:MEFV protein, human; C402202:PYCARD protein, human; D000071198:Pyrin