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Dell'Orco, D.

Publications and source records attributed to Dell'Orco, D..

2 recordsLinked to original sources

Structural analysis and genetic code expansion reveal the functional impact of NR2F1 mutations associated with BBSOA-Syndrome

Deciphering the structural effects of variants is essential for understanding the pathophysiological mechanisms of genetic diseases. Using a neurodevelopmental disorder called Bosch-Boonstra-Schaaf Optic Atrophy Syndrome (BBSOAS) as a genetic disease model, we applied a combined Genetic Code Expansion (GCE) and structural bioinformatics strategy to assess the pathogenic impact of several human NR2F1 variants. Nonsense mutations in the ligand binding domain (LBD) resulted in truncated proteins, while missense variants significantly affected the folding of NR2F1 monomers as well as its supramolecular complexes. The GCE-enabled covalent and site-specific capture of transient supramolecular interactions in living cells revealed the variable quaternary conformations of NR2F1 variants and pinpointed the disrupted interplay with dimeric partners and the newly identified cofactor, CRABP2, while the computational analyses of the NR2F1 structure delineated the molecular basis of the impact of the variants on the isolated and complexed structures. The revealed consequence of the pathogenic mutations on the conformation, supramolecular interplay, and alterations in the cell cycle, viability, and subcellular localization of the different variants reflect the heterogeneous disease spectrum and establish the foundation for further understanding the complexity of BBSOAS.

biochemistry↗

Recombinant protein delivery enables modulation of the phototransduction cascade in mouse retina

Retinal dystrophies of genetic origin are often associated with mutations in the genes involved in the phototransduction cascade in photoreceptors, a paradigmatic signaling pathway mediated by G protein-coupled receptors. Photoreceptor viability is strictly dependent on the levels of the second messengers cGMP and Ca2+. Here we explored the possibility of modulating the phototransduction cascade in mouse rods using direct or liposome-mediated administration of a recombinant protein crucial for regulating the interplay of the second messengers in photoreceptor outer segments. The effects of administration of the free and liposome-encapsulated human guanylate cyclase-activating protein (GCAP1) were compared in biological systems of increasing complexity (in cyto, ex vivo, and in vivo). Analysis of protein biodistribution and direct measurement of functional alteration in rod photoresponses show that the exogenous GCAP1 protein is fully incorporated into the mouse retina and photoreceptor outer segments. Furthermore, only in the presence of a point mutation associated with cone-rod dystrophy in humans p.(E111V), protein delivery induces a disease-like electrophysiological phenotype, consistent with constitutive activation of the retinal guanylate cyclase. Our study demonstrates that both direct and liposome-mediated protein delivery are powerful tools for targeting signaling cascades in neuronal cells, which could be particularly important for the treatment of autosomal dominant genetic diseases.

neuroscience↗