Annexin A11

Annexin A11 (ANXA11) is a calcium-binding protein of 505 amino acids that plays a role in cytokinesis, specifically required for midbody formation and completion of the terminal phase of cell division (UniProt: P50995). It binds calcyclin in a calcium-dependent manner and is expressed in human tissues.

Beyond its cell-cycle function, ANXA11 has been associated with neurodegenerative diseases. Mutations in ANXA11 cause amyotrophic lateral sclerosis 23 (ALS23), an autosomal dominant motor neuron disease featuring ubiquitin-positive inclusions and pathologic aggregates (UniProt: P50995). The protein is also implicated in inclusion body myopathy with brain white matter abnormalities (IBMWMA), an adult-onset disorder characterized by muscle weakness, cognitive decline, and cytoplasmic protein aggregates.

In Alzheimer's disease, ANXA11 is significantly upregulated in post-mortem AD brain tissue compared to age-matched controls (mean log2 fold-change = 0.17; Chaparral AD proteomics). This elevation was detected across subcellular fractions in a TMT-labeled proteomic study, suggesting involvement in AD-related pathological processes, potentially linking the protein's aggregation-related functions to amyloid and tau pathology.