PT  - JOURNAL ARTICLE
AU  - Scopa, Chiara
AU  - Barnada, Samantha M.
AU  - Cicardi, Maria E.
AU  - Singer, Mo
AU  - Trotti, Davide
AU  - Trizzino, Marco
TI  - <em>JUN</em> upregulation drives aberrant transposable element mobilization, associated innate immune response, and impaired neurogenesis in Alzheimer’s disease
AID  - 10.1101/2022.11.24.517794
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.11.24.517794
4099  - http://biorxiv.org/content/early/2022/11/24/2022.11.24.517794.short
4100  - http://biorxiv.org/content/early/2022/11/24/2022.11.24.517794.full
AB  - Adult neurogenic decline, inflammation, and neurodegeneration are phenotypic hallmarks of Alzheimer’s disease (AD). Mobilization of transposable elements (TEs) in heterochromatic regions was recently reported in AD, but the underlying mechanisms are still underappreciated. Combining functional genomics with differentiation of familial and sporadic AD patient derived-iPSCs into hippocampal progenitors, CA3 neurons, and cerebral organoids, we found that upregulation of the AP-1 subunit c-JUN triggers decondensation of genomic regions containing TEs. This leads to cytoplasmic accumulation of TE-derived RNA-DNA hybrids, activation of the cGAS-STING cascade, and increased cleaved caspase-3 levels, suggesting initiation of programmed cell death in progenitor cells and neurons. Notably, inhibiting c-JUN effectively blocks all the downstream molecular processes and rescues neuronal death and impaired neurogenesis in the AD progenitors. Our findings open new avenues for identifying therapeutic strategies and biomarkers to counteract disease progression and diagnose AD in the early, pre-symptomatic stages.Competing Interest StatementThe authors have declared no competing interest.