Genomic analyses allowed to identify genes and proteins involved inAlzheimer’s Disease (AD). In the laboratory, genetic and transcriptomic approachesrevealed two genes differentially expressed in AD: IL-33 gene, found to be underexpressedin AD cases brain, and BIN1 gene, found by GWAS analyses and overexpressedin brains of AD cases.As regards to IL-33, we observed that this protein have an impact on amyloidprecursor protein (APP) metabolism by its transcriptional regulation properties. So,we tried to identify the genes modulated by IL-33 using transcriptomic high-troughputanalyses and we identified IL-33 DNA binding sites by ChIP-on-chip approaches. Weobserved that IL-33 was involved in gene transcription and could act directly on DNAby interaction with histones. We also observed that IL-33 increase the expression ofpresenilin 2, which can explain its effect on APP metabolism.As regards to BIN1, we identified one functional polymorphism in regulatoryregion of this gene associated with AD and allowed to explain the expressionvariation of BIN1 in AD brains. We also found an interaction of BIN1 with Tau. So,BIN1 would be the first genetic risk factor for AD linked to the “Tau pathway” andcould explain the link between amyloid pathology and Tau pathology.The analyses performed in the laboratory allowed to, from genomic analysesresults, a better understanding of mechanisms involved in AD physiopathology.
