The Pathobiology of TDP-43 C-Terminal Fragments in ALS and FTLD
- PMID: 31031584
- PMCID: PMC6470282
- DOI: 10.3389/fnins.2019.00335
The Pathobiology of TDP-43 C-Terminal Fragments in ALS and FTLD
Abstract
During neurodegenerative disease, the multifunctional RNA-binding protein TDP-43 undergoes a vast array of post-translational modifications, including phosphorylation, acetylation, and cleavage. Many of these alterations may directly contribute to the pathogenesis of TDP-43 proteinopathies, which include most forms of amyotrophic lateral sclerosis (ALS) and approximately half of all frontotemporal dementia, pathologically identified as frontotemporal lobar degeneration (FTLD) with TDP-43 pathology. However, the relative contributions of the various TDP-43 post-translational modifications to disease remain unclear, and indeed some may be secondary epiphenomena rather than disease-causative. It is therefore critical to determine the involvement of each modification in disease processes to allow the design of targeted treatments. In particular, TDP-43 C-terminal fragments (CTFs) accumulate in the brains of people with ALS and FTLD and are therefore described as a neuropathological signature of these diseases. Remarkably, these TDP-43 CTFs are rarely observed in the spinal cord, even in ALS which involves dramatic degeneration of spinal motor neurons. Therefore, TDP-43 CTFs are not produced non-specifically in the course of all forms of TDP-43-related neurodegeneration, but rather variably arise due to additional factors influenced by regional heterogeneity in the central nervous system. In this review, we summarize how TDP-43 CTFs are generated and degraded by cells, and critique evidence from studies of TDP-43 CTF pathology in human disease tissues, as well as cell and animal models, to analyze the pathophysiological relevance of TDP-43 CTFs to ALS and FTLD. Numerous studies now indicate that, although TDP-43 CTFs are prevalent in ALS and FTLD brains, disease-related pathology is only variably reproduced in TDP-43 CTF cell culture models. Furthermore, TDP-43 CTF expression in both transgenic and viral-mediated in vivo models largely fails to induce motor or behavioral dysfunction reminiscent of human disease. We therefore conclude that although TDP-43 CTFs are a hallmark of TDP-43-related neurodegeneration in the brain, they are not a primary cause of ALS or FTLD.
Keywords: TDP-43; amyotrophic lateral sclerosis (ALS); frontotemporal lobar degeneration (FTLD-TDP); motor neuron disease (MND); neurodegeneration.
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References
-
- Akamatsu M., Takuma H., Yamashita T., Okada T., Keino-Masu K., Ishii K., et al. (2013). A unique mouse model for investigating the properties of amyotrophic lateral sclerosis-associated protein TDP-43, by in utero electroporation. Neurosci. Res. 77 234–241. 10.1016/j.neures.2013.09.009 - DOI - PubMed
-
- Arai T., Hasegawa M., Akiyama H., Ikeda K., Nonaka T., Mori H., et al. (2006). TDP-43 is a component of ubiquitin-positive tau-negative inclusions in frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Biochem. Biophys. Res. Commun. 351 602–611. 10.1016/j.bbrc.2006.10.093 - DOI - PubMed
-
- Arnold E. S., Ling S. C., Huelga S. C., Lagier-Tourenne C., Polymenidou M., Ditsworth D., et al. (2013). ALS-linked TDP-43 mutations produce aberrant RNA splicing and adult-onset motor neuron disease without aggregation or loss of nuclear TDP-43. Proc. Natl. Acad. Sci. U.S.A. 110 E736–E745. 10.1073/pnas.1222809110 - DOI - PMC - PubMed
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