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bioRxiv · 10.1101/2024.04.21.590446

Nanodisc reconstitution and characterization of amyloid-β precursor protein C99

Krishnarjuna, B.·Sharma, G.·Hiiuk, V. M.·Struppe, J.·Nagorny, P.·Ivanova, M. I.·Ramamoorthy, A.
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Abstract

Amyloid precursor protein (APP) plays a pivotal role in the pathology of Alzheimers disease. Since the fragmentation of the membrane-bound APP that results in the production of amyloid-beta peptides is the starting point for amyloid toxicity in AD, it is important to investigate the structure and dynamics of APP in a near-native lipid-bilayer environment. However, the reconstitution of APP into a stable/suitable membrane-mimicking lipid environment is a challenging task. In this study, the 99-residue C-terminal domain of APP is successfully reconstituted into polymer nanodiscs and characterized using size-exclusion chromatography, mass spectrometry, solution NMR, and magic-angle spinning solid-state NMR. In addition, the feasibility of using lipid-solubilizing polymers for isolating and characterizing APP in native E. coli membrane environment is demonstrated.

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Krishnarjuna, B., Sharma, G., Hiiuk, V. M., Struppe, J., Nagorny, P., Ivanova, M. I., Ramamoorthy, A.. 2024-04-21. Nanodisc reconstitution and characterization of amyloid-β precursor protein C99. https://doi.org/10.1101/2024.04.21.590446

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