α-Synuclein (α-syn) is an intrinsically disordered protein (IDP) that undergoes liquid-liquid phase separation (LLPS), fibrillation, and forms insoluble intracellular Lewy bodies in neurons, which are the hallmark of Parkinson's Disease (PD). Neurotoxicity precedes the formation of aggregates and might be related to α-syn LLPS. The molecular mechanisms underlying the early stages of LLPS are still elusive. To obtain structural insights into α-syn upon LLPS, we take advantage of cross-linking/mass spectrometry (XL-MS) and introduce an innovative approach, termed COMPASS (COMPetitive PAiring StatisticS). In this work, we show that the conformational ensemble of α-syn shifts from a "hairpin-like" structure towards more "elongated" conformational states upon LLPS. We obtain insights into the critical initial stages of LLPS and establish a novel mass spectrometry-based approach that will aid to solve open questions in LLPS structural biology.
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http://dx.doi.org/10.1002/anie.202205726 | DOI Listing |
Cells
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Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 5 1-1-1 Higashi, Tsukuba 305-8565, Ibaraki, Japan.
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SKL of Marine Food Processing & Safety Control, National Engineering Research Center of Seafood, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China.
Iron fortification with food supplements remains the primary dietary strategy for improving iron deficiency anemia (IDA). This study used Antarctic krill protein for fibrillar design to form an Antarctic krill protein amyloid fibril (AKAF). The results indicated that peptides generated by proteolysis were a prerequisite for fibril assembly, forming elongated fibril structures and cross-linking upon heating.
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Department of Chemical Engineering, Technion-IIT, Haifa 32000, Israel.
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Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; Center for Biopharmaceuticals and Biobarriers in Drug Delivery, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark. Electronic address:
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National Key Laboratory for Tropical Crop Breeding, Tropical Crop Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Sanya, Haikou, 572024/571101, Hainan, China.
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