Detection and characterization of TDP-43 in human cells and tissues by multiple reaction monitoring mass spectrometry.

Transactive response DNA-binding protein 43 kDa (TDP-43) is a highly conserved and widely expressed protein in human tissues that regulates nucleic acid processing. In frontotemporal dementia and amyotrophic lateral sclerosis, however, TDP-43 forms insoluble aggregates in central nervous tissues. These pathological deposits of TDP-43 have been primarily studied by ligand binding, namely western blot analysis, and, thus, methods with greater structural resolution are needed to aid in our understanding of the pathological processes associated with TDP-43 misfolding and aggregation. Toward this goal, we have developed a selective and multiplex method for the detection and characterization of TDP-43 using liquid chromatography tandem mass spectrometry. As proof-of-concept, the method was applied to the detection and characterization of TDP-43 in human cell lines and human brain tissue.
Competing Interests: M.L.D. reports a grant from the Alzheimer's Drug Discovery Foundation and the Association for Frontotemporal Degeneration, and Y.Z.Z. reports a fellowship from the Alzheimer Society of Canada and the Firefly Foundation, during the conduct of the study. I.R.A.M. reports personal fees from Prevail Therapeutics, outside of the submitted work. T.D.P., L.M.F, and J.G.K.L. have nothing to disclose.
(© 2019 The Association for Mass Spectrometry: Applications to the Clinical Lab (MSACL). Published by Elsevier B.V. All rights reserved.)