Poly(ADP-ribose)polymerase1 facilitates the nucleosome disassembly

Being the basic building blocks of chromatin, nucleosomes and their stability determine the genome accessibility for different DNA-dependent proteins. This characteristic is labile under all cell-life processes. One of the abundant DNA-binding proteins, which is important for genome compaction, is poly(ADP-ribose)polymerase1 (PARP1). Despite the extensive experimental data on the chromatin compaction regulation under ADP-ribosylation, the details of the interplay of nucleosome with PARP1 in the absence of protein activation remain unclear. In this study, we analyzed the changes in the nucleosome wrapping upon PARP1 interaction using a single-molecule approach -- optical tweezers. We demonstrate that PARP1 binding leads to weakening of the contacts that support the nucleosome core.