This is the amyloid, C-terminal, protein of the beta-Amyloid precursor protein (APP) which is a conserved and ubiquitous transmembrane glycoprotein strongly implicated in the pathogenesis of Alzheimer's disease but whose normal biological function is unknown. The C-terminal 100 residues are released and aggregate into amyloid deposits which are strongly implicated in the pathology of Alzheimer's disease plaque-formation. The domain is associated with family A4_EXTRA, Pfam:PF02177, further towards the N-terminus.

1: Amyloidogenicity of beta A4 and beta A4-bearing amyloid protein precursor fragments by metal-catalyzed oxidation. Dyrks T, Dyrks E, Hartmann T, Masters C, Beyreuther K; J Biol Chem. 1992;267:18210-18217. PMID:1517249

2: Peptides containing the RERMS sequence of amyloid beta/A4 protein precursor bind cell surface and promote neurite extension. Jin LW, Ninomiya H, Roch JM, Schubert D, Masliah E, Otero DA, Saitoh T; J Neurosci. 1994;14:5461-5470. PMID:8083748

3: Physiological regulation of the beta-amyloid precursor protein signaling domain by c-Jun N-terminal kinase JNK3 during neuronal differentiation. Kimberly WT, Zheng JB, Town T, Flavell RA, Selkoe DJ; J Neurosci. 2005;25:5533-5543. PMID:15944381