Abstract
Several neurodegenerative diseases including Alzheimer's Disease (AD), have characteristic ubiquitin positive pathological protein aggregates. Currently, the specific ubiquitylation protein substrates associated with these aggregates in AD brain is poorly understood. We analyzed control and AD postmortem brain tissues to examine the changes in the proteome and ubiquitylation substrates associated with AD pathology. Affinity capture using tandem ubiquitin binding entities (TUBEs) was utilized to enrich poly‐ubiquitylation substrates from AD and age‐matched control postmortem brain tissues (n=3 each group). Label‐free mass spectrometry (MS) based proteomic analysis identified a total of 2112 unique proteins across all samples and bead controls. After controlling for non‐specific binding, we identified 197 proteins that were at least two‐fold enriched in AD compared to control cases. Some of these targets include ubiquitin, Tau, p62 sequestosome and 14‐3‐3 proteins, which are known to associate with AD neuropathology. A cross comparison with previous proteomic studies revealed that 108 of those 197 proteins have increased site‐specific levels of ubiquitylation in AD brain. Tau poly‐ubiquitylation from AD brain homogenates was confirmed by affinity capture using either pan or linkage‐specific (Lys48 and Lys63) poly‐ubiquitin TUBEs and immunoblotting. These findings show the utility of MS to map ubiquitylated substrates in the human brain and provide a better understanding of the mechanisms underlying post‐translational modifications of pathological proteins in AD.Support or Funding InformationNational Institute on Aging (U01AG046161‐02, R21AG054206, 5R01AG053960, RF1AG057470, and RF1AG057471) and the NINDS Emory Neuroscience Core (P30NS055077).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
