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Hydrogen deuterium uptake comparison between wild-type, I499F, and D380A variants of the myocilin olfactomedin domain

ABSTRACT: Studies of folded-to-misfolded transitions using model protein systems reveal a range of unfolding needed for exposure of amyloid-prone regions for subsequent fibrillization. Here, we probe the relationship between unfolding and aggregation for glaucoma-associated myocilin. Mutations within the olfactomedin domain of myocilin (OLF) cause a gain-of-function, namely cytotoxic intracellular aggregation, which hastens disease progression. Aggregation by wild-type OLF (OLFWT) competes with its chemical unfolding, but only below the threshold where OLF loses tertiary structure. Representative moderate (OLFD380A) and severe (OLFI499F) disease variants aggregate differently, with rates comparable to OLFWT in initial stages of unfolding, and variants adopt distinct partially folded structures seen along the OLFWT urea-unfolding pathway. Whether initiated with mutation or chemical perturbation, unfolding propagates outward to the propeller surface. In sum, for this large protein prone to amyloid formation, the requirement for a conformational change to promote amyloid fibrillization leads to direct competition between unfolding and aggregation.

INSTRUMENT(S): ACQUITY UPLC

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Minh Thu Ma

LAB HEAD: Raquel L Lieberman

PROVIDER: PXD045520 | Pride | 2023-11-27

REPOSITORIES: Pride

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			Action	DRS
	D380A_OLF.DnX	Other
	D380A_OLF_cluster_data.csv	Csv
	D380A_OLF_relative_uptake_plots.zip	Other
	D380A_OLF_sequence.txt	Txt
	D380A_OLF_state_data.csv	Csv

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