Integrative Bioinformatics Across Proliferative and Non-Proliferative Cell States Reveals Novel Cytokinesis Genes

Abstract

The mammalian heart has no significant endogenous regenerative capacity, as mammalian cardiomyocytes undergo a last round of cell cycle after birth, becoming post-mitotic and polyploid. Consistent with this, cytokinesis inhibition in zebrafish impairs their cardiac regenerative capacity. Notably, re-induction of cell cycle progression or polyploidization reduction through cytokinesis generates proliferative mammalian cardiomyocytes. Thus, a better understanding of cytokinesis is fundamental. Here, we adopted an integrative bioinformatics approach to identify novel common candidate cytokinesis genes by comparing proliferative and non-proliferative cell states. The approach relies on (i) a temporal expression dataset profiling rat ventricles during heart development, (ii) a transcriptomics dataset profiling postnatal rat cardiomyocytes upon stimulation with pro-proliferative compounds, and (iii) an expression dataset profiling mouse embryonic fibroblasts upon knockout of Lin9, a master regulator of cell division. Following prioritization of the identified 236 novel candidate cytokinesis genes and literature-based investigations, Car8, Sox11, Arl6ip1, and Sc5d underwent experimental validation. Protein localization studies in HeLa cells revealed distinct localization patterns during cytokinesis for CA8 and SC5D. Their knockdown in Hct116 cells resulted in increased multinucleation. These findings highlight that leveraging integrative bioinformatics across different proliferative states can uncover novel candidate cytokinesis genes, contributing to the establishment of potential therapeutic targets to treat proliferative diseases and/or to promote regeneration.