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Clustering of Tau Fibrils Impairs the Synaptic Composition of ?3-Na+/K+-ATPase and AMPA receptors

ABSTRACT: Tau assemblies have prion-like properties: they propagate from one neuron to another and amplify by seeding the aggregation of endogenous Tau. Although key in prion-like propagation, the binding of exogenous Tau assemblies to the plasma membrane of naïve neurons is not understood. We report that fibrillar Tau form clusters at the plasma membrane following lateral diffusion. We found that the fibrils interact with the Na+/K+-ATPase (NKA), and AMPA receptors. The consequence of the clustering is a reduction in the amount of ?3-NKA and an increase in the amount of GluA2-AMPA receptor at synapses. Furthermore, fibrillar Tau destabilizes functional NKA-complexes. Tau and ?-synuclein aggregates often co-exist in patients' brains. We now bring evidences for cross-talk between these pathogenic aggregates with -synuclein fibrils dramatically enhancing fibrillar Tau clustering and synaptic localization. Our results suggest that fibrillar -synuclein and Tau cross-talk at the plasma membrane imbalances neuronal homeostasis.

SUBMITTER: Dr. Amulya, Nidhi Shrivastava

PROVIDER: S-SCDT-EMBOJ-2018-99871 | biostudies-other |

REPOSITORIES: biostudies-other

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Clustering of Tau fibrils impairs the synaptic composition of ?3-Na+/K+-ATPase and AMPA receptors.

Project description:Tau assemblies have prion-like properties: they propagate from one neuron to another and amplify by seeding the aggregation of endogenous Tau. Although key in prion-like propagation, the binding of exogenous Tau assemblies to the plasma membrane of naïve neurons is not understood. We report that fibrillar Tau forms clusters at the plasma membrane following lateral diffusion. We found that the fibrils interact with the Na+/K+-ATPase (NKA) and AMPA receptors. The consequence of the clustering is a reduction in the amount of ?3-NKA and an increase in the amount of GluA2-AMPA receptor at synapses. Furthermore, fibrillar Tau destabilizes functional NKA complexes. Tau and ?-synuclein aggregates often co-exist in patients' brains. We now show evidences for cross-talk between these pathogenic aggregates with ?-synuclein fibrils dramatically enhancing fibrillar Tau clustering and synaptic localization. Our results suggest that fibrillar ?-synuclein and Tau cross-talk at the plasma membrane imbalance neuronal homeostasis.

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