SERPINB1

The protein encoded by this gene is a member of the serpin family of proteinase inhibitors. Members of this family maintain homeostasis by neutralizing overexpressed proteinase activity through their function as suicide substrates. This protein inhibits the neutrophil-derived proteinases neutrophil elastase, cathepsin G, and proteinase-3 and thus protects tissues from damage at inflammatory sites. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2012]

Serpin Family B Member 1

Neutrophil serine protease inhibitor that plays an essential role in the regulation of the innate immune response, inflammation and cellular homeostasis (PubMed:30692621).
Acts primarily to protect the cell from proteases released in the cytoplasm during stress or infection. These proteases are important in killing microbes but when released from granules, these potent enzymes also destroy host proteins and contribute to mortality. Regulates the activity of the neutrophil proteases elastase, cathepsin G, proteinase-3, chymase, chymotrypsin, and kallikrein-3 (PubMed:11747453, PubMed:30692621).
Acts also as a potent intracellular inhibitor of GZMH by directly blocking its proteolytic activity (PubMed:23269243).
During inflammation, limits the activity of inflammatory caspases CASP1, CASP4 and CASP5 by suppressing their caspase-recruitment domain (CARD) oligomerization and enzymatic activation (PubMed:30692621).
When secreted, promotes the proliferation of beta-cells via its protease inhibitory function (PubMed:26701651).

Biological Process negative regulation of endopeptidase activityManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process negative regulation of interleukin-1 beta productionManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process type B pancreatic cell proliferationManual Assertion Based On ExperimentIDA:UniProtKB

Secreted
Cytoplasm
Cytolytic granule
Early endosome