Fig. 2
From: Regional correlation of biochemical measures of amyloid and tau phosphorylation in the brain
MTBR-tau is enriched in AD brain insoluble extracts in the first cohort. Enrichment profile of MTBR-tau peptides in insoluble extracts from AD (n = 15; seven or eight brain regions from two participants), Abeta+ (n = 14; seven brain regions from two participants), and control brains (n = 12; six brain regions from two participants) were analyzed by mass spectrometry. Relative abundance of tau peptides was quantified relative to mid-domain (residue 181-190) peptide for internal normalization. MTBR-tau-243 (residue 243-254), MTBR-tau-299 (residues 299-317), and MTBR-tau-354 (residues 354-369) were highly enriched in the AD brains compared to Abeta+ and controls. MTBR-tau-299 and MTBR-tau-354 are located inside the filament core of AD aggregates [12]. Unmodified residues 195-209 decreased in AD brains, potentially due to a higher phosphorylation in AD. Data are represented as mean ± SEM