Regulation of gene expression using the RNA interference (RNAi) technology is a promising therapeutical approach with real perspective for clinical translation. Several clinical trials are already in course but none of them was proved to tackle brain diseases yet. In our laboratory, we have developed an RNAi against the mRNA of the tyrosine kinase fyn aimed to reduce the levodopa induced dyskinesia in Parkinson’s disease. Combined with lentiviral delivered into the striatum, we have reduced dyskinesia in experimental mice (Bordone 2021). Although the viral transduction was restricted only to the injected areas, fyn expression is ubiquitous throughout the brain and then we envisage to develop further precision of silencing among neuronal subtypes. We expect to generate a molecular scalpel to provide a fine therapeutic option that will reduce side effects.
To reach this goal we have designed a strategy using a modified Cre-LoxP system to restrict expression of RNA molecules into dopamine D1R-expressing neurons. We have cloned the synapsin promoter inverted between lox71/lox66 sequences upstream the EGFP reporter sequence. Then, the expression of EGFP will occur only in the presence of the recombinase Cre. In this poster we will discuss our strategy and show the first trials in vitro and in vivo to evaluate the correct functioning of the system. If recombination works with the reporter, the RNAi against fyn will be cloned instead of EGFP and will be tested in dyskinetic mice.