Project description:Numerous genes mutated in amyotrophic lateral sclerosis (ALS) share a role in DNA damage and repair, emphasizing genome disintegration in ALS. DNA instability and repair mechanisms segregate extrachromosomal circular DNAs (ec/eccDNAs) that can modulate gene expression somatically. Here, circulome profiling in a hSOD1G93A genotoxicity model of ALS revealed a 6-fold enrichment of small-size eccDNAs relative to controls. DifCir-based differential analysis identified 189 genes with patterned segregation of differentially produced per gene circles (DPpGCs) from ALS but not from control samples, implicating an inter-sample recurrence rate of at least 89% for the top 6 DPpGCs. Mass spectrometry-based ALS circulome-proteome cross-referencing revealed 31 corresponding differentially expressed proteins (DEPs), with 12 DPpGC-DEP pairs being itemized in ALS risk GWAS databases. DPpGC-DEP hotspots mainly convey neuron-specific functions counteracting ALS detriments. This is unanticipated evidence for non-random, profiled eccDNA accumulation in ALS neurodegeneration, involving putative interactions with their gene products as well as biomarker perspectives.
Project description:Differentiated motor neurons from hiPSC derived from peripheral nerve fibroblasts of sporadic ALS patients and evaluated the gene expression profile by means microarray-linked to specific analysis tools. Two-condition experiment, ALS patients motor neurons vs. controls. Biological replicates: 3 ALS replicates, 3 control replicates.