Frontotemporal lobar degeneration (FTLD), a common cause of early-onset dementia, encompasses a group of disorders with significant genetic, clinical and neuropathological heterogeneity. Understanding the diverse underlying mechanisms of FTLD pathogenesis is a fundamental area of interest of my research program. To accelerate scientific discovery, we have adopted a comprehensive approach that investigates multiple FTLD mechanisms driven by key molecular players (e.g., TDP-43, progranulin, and tau). We also place great emphasis on translational research geared towards identifying much needed biomarkers and therapies, an area of particular importance given that there exists no treatment for FTLD. Our endeavors to uncover the pathomechanisms associated with TDP-43, tau and FTLD-causing mutations have yielded seminal findings published in high-impact journals. For instance, in the five years since the discovery of the G4C2 repeat expansions in C9ORF72 as the most common known cause of FTLD, my group identified a new neuropathological hallmark specific to this mutation, namely the accumulation of proteins of repeating dipeptides synthesized from the expansion; made significant strides in elucidating mechanisms of disease relating to these so-called c9RAN proteins; identified promising therapeutic strategies and potential biomarkers for C9ORF72 repeat expansion carriers; and developed the first mouse model to recapitulate both neuropathological and clinical features of patients. Our productivity is influenced by the excellent research environment fostered at Mayo Clinic, which brings together highly interactive and devoted neurobiologists, geneticists, neuropathologists and physician scientists, as well as the numerous collaborations we have forged with world-renowned experts in the field. Herein, we propose to extend our discoveries by addressing impactful questions, some of which may be high risk, but all with clear potential to be transformative to the field. Of importance, the nature of the R35 mechanism will allow us the flexibility to explore intriguing new directions that emerge from our findings and those of others, ensuring that our studies remain timely and relevant. Overall, with the goal of advancing our understanding and developing therapies for FTLD, we propose mechanistic and translational investigations relating to three main areas: 1) C9ORF72-linked FTLD-TDP; 2) GRN-linked FTLD-TDP; and 3) FTLD-Tau. We will explore various therapeutic approaches, seek to identify disease-relevant biomarkers in cerebrospinal fluid and blood, and develop and improve FTLD animal models.

Public Health Relevance

Frontotemporal lobar degeneration (FTLD) is a progressive neurodegenerative disease negatively affecting the personality, behavior and language of patients, for which there is no cure. Our goals are to define the abnormal processes that contribute to the development of FTLD, as well as devise strategies to monitor and prevent disease progression. The novel insight and translational nature of our findings are expected to transform the field and improve the prognosis for patients with FTLD.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Unknown (R35)
Project #
1R35NS097273-01
Application #
9156105
Study Section
Special Emphasis Panel (ZNS1)
Program Officer
Sutherland, Margaret L
Project Start
2016-12-01
Project End
2024-11-30
Budget Start
2016-12-01
Budget End
2017-11-30
Support Year
1
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Mayo Clinic Jacksonville
Department
Type
DUNS #
153223151
City
Jacksonville
State
FL
Country
United States
Zip Code
32224
Gendron, Tania F; C9ORF72 Neurofilament Study Group; Daughrity, Lillian M et al. (2017) Phosphorylated neurofilament heavy chain: A biomarker of survival for C9ORF72-associated amyotrophic lateral sclerosis. Ann Neurol 82:139-146
Mackenzie, Ian R; Nicholson, Alexandra M; Sarkar, Mohona et al. (2017) TIA1 Mutations in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia Promote Phase Separation and Alter Stress Granule Dynamics. Neuron 95:808-816.e9
Prudencio, Mercedes; Gonzales, Patrick K; Cook, Casey N et al. (2017) Repetitive element transcripts are elevated in the brain of C9orf72 ALS/FTLD patients. Hum Mol Genet 26:3421-3431
DeJesus-Hernandez, Mariely; Finch, NiCole A; Wang, Xue et al. (2017) In-depth clinico-pathological examination of RNA foci in a large cohort of C9ORF72 expansion carriers. Acta Neuropathol 134:255-269
Lee, Chris W; Stankowski, Jeannette N; Chew, Jeannie et al. (2017) The lysosomal protein cathepsin L is a progranulin protease. Mol Neurodegener 12:55
Carlomagno, Yari; Chung, Dah-Eun Chloe; Yue, Mei et al. (2017) An acetylation-phosphorylation switch that regulates tau aggregation propensity and function. J Biol Chem 292:15277-15286
Finch, NiCole A; Wang, Xue; Baker, Matthew C et al. (2017) Abnormal expression of homeobox genes and transthyretin in C9ORF72 expansion carriers. Neurol Genet 3:e161
Gendron, Tania F; Chew, Jeannie; Stankowski, Jeannette N et al. (2017) Poly(GP) proteins are a useful pharmacodynamic marker for C9ORF72-associated amyotrophic lateral sclerosis. Sci Transl Med 9: