Dr. Gan will extend her discovery of the role of tau acetylation to tau degradation and synaptic toxicity. Her more recent studies in human cells showed that either elevating tau acetylation or neuronal activity enhances tau release, but the mechanism is unknown. Moreover, induced pluripotent stem cell (iPSC)-derived neurons carrying the V337M mutation are hyperactive and release more tau to the extracellular space.
Building upon these findings, project 1 proposes three specific aims:
- Define FTD mutations-induced aberrant tau PTMs and dissect how acetylation stimulates tau release
- Determine how FTLD-tau alters neuronal activity and activity-dependent tau release
- Determine the functional consequence and mechanisms underlying pathogenic seeding
Dr. Kosik has established a robust system to detect transcriptomic changes associated with tau inclusions at the single-cell level, providing the ideal control data from adjacent unaffected single cells. In addition, an in-house designed patterned multi-electrode array will allow the group to address signal propagation and hyper-excitability that alters network activity.
Project 2 proposes three aims:
- Profile transcriptome alternations induced by tau mutations and tau inclusions
- Define the consequences of tau inclusions or mutant tau on neural excitability, conductivity, and connectivity
- Use unbiased CRISPR library screening (with the CRISPR core) to define mechanisms of tau uptake
Dr. Cuervo will investigate the role of three autophagy pathways in modulating tau proteostasis, and conversely, the impact of mutant tau on the normal functioning of these three autophagic pathways. Furthermore, project 3 will study the contribution of tau-mediated autophagy changes on neuronal activity.
Project 3 proposes three aims:
- Analyze the effect of intra- and extracellular pathogenic tau proteins on selective forms of neuronal autophagy
- Investigate the effect of changes in autophagic pathways activity on excitability and tau uptake/accumulation in human neurons
- Identify FTD-specific differences in the association of tau with autophagic compartments in human brain
Mass Spectrometry (MS) technology center
The MS technology center will support the three projects to systematically examine PTMs using a global to targeted MS-based quantitative approach, as well as PPIs using a combination of AP-MS and proximity-based biotinylation. The data produced by the MS facility is a cornerstone of the proposed work and is essential for the success of the individual projects. Their strong computational expertise will be integrated with the Data core (see below) to provide in-depth data analyses and generate high-quality datasets to be integrated into public databases as resources for the scientific community.
The CRISPR core contributes to West cWOW by providing reagents and experimental expertise to the projects by repressing and activating genes in human iPSC-derived neurons. The CRISPR core will also conduct unbiased genome-wide screens to uncover cellular factors controlling tau uptake and template aggregation, which are potential therapeutic targets and biomarkers for tauopathies. This platform is critical for validating the functional roles of cellular factors investigated by all projects to uncover novel factors with therapeutic potential.
The Human core will help the center meet its overall goals by:
- Directly supporting all three projects, which will rely on well-characterized and carefully processed/preserved human tissue, bio-fluids, and cells from tauopathy patients and controls;
- Validating results from all projects in human specimens; and
- Developing enhanced tools for conducting state-of-the-art multiplex assays in human specimens, thus allowing scaling of the in vitro assays.
The Data core accelerates the center’s communication, progress, and data sharing. The Data core’s activities towards these goals will be distributed across three main areas, corresponding to the three specific aims:
- Facilitate communication, collaboration, and sharing within the center
- Analyze data in collaboration with center investigators and other cores
- Share high-throughput data generated by the center with the research community through the use of government and nongovernment-sponsored public databases.
The Admin core will be the nexus of an efficient governance structure. It will coordinate communications among the researchers in each project, between projects and the cores, between the center and the internal Executive Steering Committee and the external Scientific Advisory Committee, and between the center and the administration of the five sites, NINDS program staff, and the other national centers on FTD.