High levels of the cold shock protein Y-box-binding protein-1, YB-1, are tightly correlated with increased cell proliferation and progression. However, the precise mechanism by which YB-1 regulates proliferation is unknown. Here, we found that YB-1 depletion in several cancer cell lines and in immortalized fibroblasts resulted in cytokinesis failure and consequent multinucleation. Rescue experiments indicated that YB-1 was required for completion of cytokinesis. Using confocal imaging we found that YB-1 was essential for orchestrating the spatio-temporal distribution of the microtubules, β-actin and the chromosome passenger complex (CPC) to define the cleavage plane. We show that phosphorylation at six serine residues was essential for cytokinesis, of which novel sites were identified using mass spectrometry. Using atomistic modelling we show how phosphorylation at multiple sites alters YB-1 conformation, allowing it to interact with protein partners. Our results establish phosphorylated YB-1 as a critical regulator of cytokinesis, defining precisely how YB-1 regulates cell division.

Autism Spectrum Disorders (ASD) encompass a group of neurodevelopmental disorders in which an affected individual faces challenges in social interaction and communication, along with restricted and repetitive stereotypic behavioral patterns and interests. In this work, we have studied the differential gene regulation between patients and controls, mediated by Transcription Factors (TFs), of key genes involved in ASD. Nine and seven TFs have been identified as potential regulators of the set of syndromic and non-syndromic key high confident genes retrieved by the Simons Foundation Autism Research Initiative (SFARI) database. We have also identified significant couples of Transcription Factor - Target Gene potentially associated with an altered regulation in ASD patients. Consistently, many identified couples are involved in processes associated with brain morphogenesis and development. In this regard, this biased regulation could be the target of some experimental design in order to 1) test this hypothesis and 2) try to target this altered regulation pattern in ASD samples. In conclusion, we would like to emphasize that the present work proposes an effective and reliable computational approach that could be applied to any disease with known key genes and available gene expression data.