Biology subjects

Ferracci, G.

Publications and source records attributed to Ferracci, G..

3 recordsLinked to original sources

bioRxiv2023

LDLR-mediated targeting and productive uptake of siRNA-peptide ligand conjugates in vitro and in vivo

siRNAs have become one of the most promising therapeutic agents because of their specificity and their potential to modulate the expression of gene-related diseases. Any gene of interest can be potentially up or down-regulated, making RNA-based technology the healthcare breakthrough of our era. However, the functional and specific delivery of siRNAs into tissues of interest and into the cytosol of target cells remains highly challenging, mainly due to the lack of efficient and selective delivery systems. Among the variety of carriers for siRNA delivery, peptides have become essential candidates because of their high selectivity, stability and conjugation versatility. Here, we describe the development of molecules encompassing siRNAs against SOD1, conjugated to peptides that target the LDLR, and their biological evaluation both in vitro and in vivo. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/526778v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@11146borg.highwire.dtl.DTLVardef@1537ee2org.highwire.dtl.DTLVardef@af67b5org.highwire.dtl.DTLVardef@1c1d7ec_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGRAPHICAL ABSTRACTC_FLOATNO C_FIG

biochemistry↗

bioRxiv2021

The protein-binding pocket of Botulinum neurotoxin B accommodates a preassembled synaptotagmin / ganglioside complex

Botulinum neurotoxin serotype B (BoNT/B) uses two separate protein and polysialoglycolipid-binding pockets to interact with synaptotagmin 1/2 and gangliosides. However, an integrated model of BoNT/B bound to its neuronal receptors in a native membrane topology is still lacking. Using a panel of in silico and experimental approaches, we present here a new model for BoNT/B binding to neuronal membranes, in which the toxin binds to a preassembled synaptotagmin-ganglioside GT1b complex and a free ganglioside allowing a lipid-binding loop of BoNT/B to interact with the glycone part of the synaptotagmin-associated GT1b. Furthermore, our data provide molecular support for the decrease in BoNT/B sensitivity in Felidae that harbor the natural variant synaptotagmin2-N59Q. These results reveal multiple interactions of BoNT/B with gangliosides and support a novel paradigm in which a toxin recognizes a protein/ganglioside complex.

pharmacology and toxicology↗

bioRxiv2021

Sequential binding of zinc triggers tau aggregation

Tau protein has been extensively studied due to its key roles in microtubular cytoskeleton regulation and in the formation of aggregates found in some neurodegenerative diseases. Recently it has been shown that zinc is able to induce tau aggregation by interacting with several binding sites. However, the precise location of these sites and the molecular mechanism of zinc-induced aggregation remain unknown. Here we used Nuclear Magnetic Resonance (NMR) to identify zinc binding sites on hTau40 isoform. These experiments revealed three distinct zinc binding sites on tau, located in the N-terminal part (H14, H32, H94, and H121), the repeat region (H299, C322, H329 and H330) and the C-terminal part (H362, H374, H388 and H407). Further analysis enabled us to show that the C-terminal and the N-terminal sites are independent of each other. Using molecular simulations, we modeled the structure of each site in a complex with zinc. Given the clinical importance of zinc in tau aggregation, our findings pave the way for designing potential therapies for tauopathies. HighlightsO_LIZinc is known to induce tau aggregation in neurodegenerative diseases C_LIO_LIZinc binding locations and mechanism are not yet clear C_LIO_LIUsing NMR we localized 3 zinc binding site on tau C_LIO_LIBy molecular simulations, we proposed a modeled structure of each site C_LIO_LIOur findings pave the way for designing potential therapies for tauopathies C_LI

molecular biology↗