Serpinb3d
Serpinb3d completes the four-gene mouse Serpinb3a-d tandem cluster on chromosome 1, an intracellular serpin group whose human relatives include SCCA1 and SCCA2. Like its siblings, Serpinb3d is predicted to encode a non-secreted serpin acting within the cytoplasm of epithelial cells, inhibiting papain-like cysteine proteases and chymotrypsin-like serine proteases to protect barrier tissues from proteolytic injury. Cluster transcripts are co-induced in skin inflammation, allergic airway disease, and carcinogen-challenge models, but Serpinb3d remains the least individually characterized paralog, with most data coming from cluster-wide genomic and expression studies. Recombinant Serpinb3d is therefore a tool for assigning paralog-specific protease targets and validating knockout-genotyping reagents.
