Scinderin

Scinderin (SCIN) is a calcium-dependent actin filament-severing protein that regulates exocytosis by modulating microfilament organization beneath the plasma membrane (UniProt: Q9Y6U3). The protein also exhibits barbed end capping and nucleating activities in the presence of Ca²⁺, and its severing activity is inhibited by phosphatidylinositol 4,5-bisphosphate. Beyond exocytosis, scinderin participates in megakaryocyte differentiation, osteoclastogenesis, and chondrocyte regulation, with roles in cell proliferation inhibition and tumorigenesis suppression via MAPK, p38, and JNK signaling pathways.

Scinderin is broadly expressed across tissues involved in cytoskeletal dynamics and secretory function. No primary disease association is documented in UniProt, though its regulatory functions suggest potential relevance to conditions affecting membrane trafficking and cell differentiation.

In Alzheimer's disease, scinderin is upregulated in post-mortem human brain tissue compared to age-matched controls, with a mean log₂ fold-change of 1.11 across four subcellular fractions (P2, P3, S2, S3) measured by TMT-labeled quantitative proteomics (Chaparral AD proteomics). This elevation may reflect compensatory cytoskeletal remodeling or altered exocytotic processes in the AD brain.