Fig. 1.

Proteomic comparison reveals that U1-70K and U1A are enriched in the sarkosyl-insoluble proteome of AD. (A) Scheme for profiling the aggregated proteins in AD postmortem brains, with nondemented cases as controls (Ctl). (B) A stained SDS gel showing detergent-insoluble proteins in one set of pooled control and AD cases. (C) Similar proteomics analysis of seven groups of neurodegenerative disease samples. One set of sarkosyl-insoluble fractions was immunoblotted by phosphorylated tau antibodies to confirm tauopathies. (D) Relative level of representative sarkosyl-insoluble proteins across different diseases. The level was estimated by spectral counts of these identified proteins, and normalized to set the maximum to 100. Two replicates were analyzed, and the bars indicate the values of mean ± SEM. (E–I) Western blotting analysis of U1-70K or U1A in biochemical brain extracts from control and neurodegenerative cases, and the strategy for protein sequential extraction. The case numbers are shown. B, blank. The exposure time was longer in I Left than in others. At least one AD sample and one control sample were loaded on every gel for comparison.