Ubiquitin-like FUBI-ribosomal protein eS30 fusion protein

FAU (Ubiquitin-like FUBI-ribosomal protein eS30 fusion protein) is a 133-amino acid protein that functions as a component of the 40S ribosomal subunit, contributing to ribosome assembly and function (UniProt: P62861). The protein may also possess pro-apoptotic activity. FAU is expressed in human tissues and plays a role in translational machinery.

FAU is downregulated in Alzheimer's Disease brain tissue. Analysis of post-mortem AD brain compared to age-matched controls using TMT-labeled tandem mass spectrometry across four subcellular fractions (P2, P3, S2, S3) demonstrated a mean log2 fold-change of −1.04 (Chaparral AD proteomics). The direction of change was consistent across the examined fractions, indicating reduced FAU protein levels in AD pathology.

The functional significance of FAU downregulation in AD remains to be established. Given FAU's ribosomal role and potential pro-apoptotic properties, altered expression may relate to disrupted protein synthesis or dysregulated cell death pathways in neurodegeneration, though this requires further mechanistic investigation.