title: The structural integrity of TDP-43 N-terminus is required for efficient aggregate entrapment and consequent loss of protein function.
abstract: Nuclear factor TDP-43 has been shown to play a key role in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia, where TDP-43 aggregates accumulate in patient's affected neurons and this event can cause neuronal dysfunction. A major focus of today's research is to discover the critical factors that lead to TDP-43 aggregation and the consequences for neuronal metabolism. From a structural point of view, several lines of evidence point toward TDP-43 C-terminus as a key domain able to mediate this process. Regarding this region, we have recently described a novel cellular TDP-43 aggregation model based on 12 tandem repetitions of its 339-366 Q/N rich prion-like domain. In addition, we have shown and confirmed that a minimal TDP-43 construct constituted by the N and C-terminal regions, but lacking both RRM domains, induce aggregation of endogenous TDP-43 and leads to its total loss of function as seen by changes in the alternative splicing of endogenous genes. In this work, we further characterize this model and show the importance of the N-terminus structure in the loss of function process. In addition, from a biochemical point of view we report that, as shown in a previous version of this model (GFP 12 × Q/N), the endogenous TDP-43 trapped in the aggregates undergoes the 2 most important post-translational modifications seen in pathological TDP-43 inclusions: ubiquitination and hyperphosphorylation.
authors: a International Centre for Genetic Engineering and Biotechnology (ICGEB) ; Trieste , Italy.
authors: Valentina
authors: V
authors: Romano
authors: Zainuddin
authors: Z
authors: Quadri
authors: Francisco E
authors: FE
authors: Baralle
authors: Emanuele
authors: E
authors: Buratti
mesh_terms: D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D057809:HEK293 Cells; D006801:Humans; D008954:Models, Biological; D010766:Phosphorylation; D066329:Protein Aggregates; D066263:Protein Aggregation, Pathological; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship; D054875:Ubiquitination
chemical_list: D004268:DNA-Binding Proteins; D066329:Protein Aggregates
keywords: ALS; ALS, amyotrophic lateral sclerosis; FTD, frontemportal dementia; GFP, green fluorescent protein; RRM, RNA recognition motif; TDP-43; TDP-43, TAR DNA binding protein 43; Ub-HA, Ubiquitin-HA; hnRNP, heterogeneous ribonucleoproteins; post-translational modifications; prion; protein aggregation
references: Ann Neurol. 2008 Jul;64(1):60-70
references: 18546284
references: EMBO J. 2001 Apr 2;20(7):1774-84
references: 11285240
references: Arch Biochem Biophys. 2014 Mar 1;545:53-62
references: 24440310
references: J Cell Sci. 2008 Nov 15;121(Pt 22):3778-85
references: 18957508
references: Front Mol Neurosci. 2014 Jun 24;7:57
references: 25009465
references: Nucleic Acids Res. 2005;33(18):6000-10
references: 16254078
references: Hum Mol Genet. 2015 Jan 1;24(1):9-20
references: 25122661
references: J Biol Chem. 2010 Aug 20;285(34):26304-14
references: 20554523
references: EMBO J. 2011 Jan 19;30(2):277-88
references: 21131904
references: Proc Natl Acad Sci U S A. 2014 Dec 30;111(52):18619-24
references: 25503365
references: Science. 2006 Oct 6;314(5796):130-3
references: 17023659
references: Am J Hum Genet. 2004 Jun;74(6):1322-5
references: 15195661
references: J Biol Chem. 2014 Dec 5;289(49):34389-407
references: 25339173
references: PLoS One. 2014;9(2):e88284
references: 24505464
references: Hum Mol Genet. 2013 Aug 1;22(15):3112-22
references: 23575225
references: J Biol Chem. 2012 Mar 2;287(10):7512-25
references: 22235134
references: Nat Struct Mol Biol. 2011 Jul;18(7):822-30
references: 21666678
references: Biochem Biophys Res Commun. 2006 Dec 22;351(3):602-11
references: 17084815
references: FEBS Lett. 2008 Aug 20;582(19):2899-904
references: 18656473
references: Nat Rev Neurol. 2010 Apr;6(4):211-20
references: 20234357
references: Mol Neurodegener. 2010 Aug 30;5:33
references: 20804554
references: Hum Mol Genet. 2014 Dec 20;23(25):6863-77
references: 25113748
references: J Biol Chem. 2011 May 27;286(21):18664-72
references: 21454603
references: Nat Rev Neurosci. 2012 Jan;13(1):38-50
references: 22127299
references: PLoS One. 2011;6(8):e23075
references: 21850253