Project description:Here we analyse transcriptome profiles within the frontal cortex between wild type, heterozygous and homozygous TDP-43 Q331K knock-in mice
Project description:Here we analyse transcriptome profiles within the frontal cortex between wild type, heterozygous and homozygous TDP-43 Q331K knockin mice at 20 months of age (C57BL/6)
Project description:Here we analyse transcriptome profiles from laser captured lower motor neurons between wild type, heterozygous and homozygous TDP-43 Q331K knockin mice
Project description:No treatment for frontotemporal dementia (FTD), the second most common type of early-onset dementia, is available, but therapeutics are being investigated to target the 2 main proteins associated with FTD pathological subtypes: TDP-43 (FTLD-TDP) and tau (FTLD-tau). Testing potential therapies in clinical trials is hampered by our inability to distinguish between patients with FTLD-TDP and FTLD-tau. Therefore, we evaluated truncated stathmin-2 (STMN2) as a proxy of TDP-43 pathology, given the reports that TDP-43 dysfunction causes truncated STMN2 accumulation. Truncated STMN2 accumulated in human induced pluripotent stem cell–derived neurons depleted of TDP-43, but not in those with pathogenic TARDBP mutations in the absence of TDP-43 aggregation or loss of nuclear protein. In RNA-Seq analyses of human brain samples from the NYGC ALS cohort, truncated STMN2 RNA was confined to tissues and disease subtypes marked by TDP-43 inclusions. Last, we validated that truncated STMN2 RNA was elevated in the frontal cortex of a cohort of patients with FTLD-TDP but not in controls or patients with progressive supranuclear palsy, a type of FTLD-tau. Further, in patients with FTLD-TDP, we observed significant associations of truncated STMN2 RNA with phosphorylated TDP-43 levels and an earlier age of disease onset. Overall, our data uncovered truncated STMN2 as a marker for TDP-43 dysfunction in FTD.
Project description:Transgenic (Tg) mice expressing nuclear or cytoplasmic human TDP-43 were generated. Tg mice had motor spasticity and forebrain neurodegeneration. Human TDP-43 reduced mouse TDP-43 in nuclei of affected neurons. Tg mice showed alterations in transcripts related to chromatin assembly. Cerebral cortex from 21 transgenic mice and controls were assayed after two weeks off doxycyline diet as described in Igaz et al.
Project description:FUS/TLS and TDP-43 are RNA/DNA-binding proteins integrally involved in amyotrophic lateral sclerosis (ALS) and frontal temporal dementia. FUS/TLS is shown to bind RNAs from >5,500 genes in mouse and human brain, primarily through a GUGGU binding motif. A characteristic sawtooth-like binding pattern is identified, supporting co-transcriptional deposition of FUS/TLS. Depletion of FUS/TLS from the adult nervous system is shown to alter levels or splicing of >970 mRNAs, most of which are distinct from the RNAs whose maturation is dependent on TDP-43. Nonetheless, only 55 RNAs are reduced upon depletion of either TDP-43 or FUS/TLS from mouse brain and human neurons differentiated from pluripotent stem cells, including mRNAs transcribed from genes with exceptionally long introns and that encode proteins essential for neuronal integrity. A subset of these is significantly lowered in FUS/TLSR521G and TDP-43G298S mutant fibroblasts and in TDP-43 aggregate-containing motor neurons in sporadic ALS, evidence pointing to a common loss-of-function pathway as one component underlying motor neuron death from misregulation of TDP-43 or FUS/TLS. Microarray of Fus/Tls in 8 week mouse brain
