Kinetic proofreading in chromatin remodeling: the case of ISWI/ACF.

For activation or repression of genes in eukaryotic organisms, the chromatin structure has to be adapted. This action is performed at least in part by dedicated motor proteins, the chromatin remodeling complexes. Recently, investigators have shown some interest in explaining how specific nucleosomes are targeted for chromatin remodeling. For this purpose, two kinetic proofreading scenarios for gene activation and repression have been put forward. We reanalyze both scenarios and show their common points and differences. Further, we propose that in gene repression by ISWI/ACF remodelers, which involves the generation of regular nucleosomal arrays, an additional proofreading step may be active.