Protein S100-A6

S100-A6 is a small calcium-binding protein that functions as a calcium sensor and modulator in cellular signaling pathways (UniProt: P06703). It binds two calcium ions cooperatively and may regulate actin cytoskeleton reorganization and cell motility through interactions with TPR-containing proteins. The protein is 90 amino acids in length.

S100-A6 is expressed in multiple tissues and participates in calcium-dependent cellular processes. UniProt records no primary disease associations in its curated database, though the protein has been noted in contexts of microbial infection.

S100-A6 is upregulated in Alzheimer's disease brain tissue. Analysis of post-mortem AD brain compared to age-matched controls using TMT-labeled quantitative proteomics across four subcellular fractions (P2, P3, S2, S3) identified S100-A6 as significantly elevated with a mean log2 fold-change of 1.16 (Chaparral AD proteomics). This upregulation suggests a potential role in AD pathophysiology, though the specific contribution remains to be elucidated.