Investigation of the Genomic Landscape of Linker Histone 1 Subtypes Uncovers Differences among Variants and a Potential Dual Behaviour of H1X Subtype in Human Cervical Cancer Cells

Abstract

Human cells contain seven somatic histone H1 variants (H1.1 to H1.5, H1.0 and H1X). Although some advances have been recently achieved in the understanding of the H1 subtypes genomic distribution, whether they present specific functions or they do have redundant roles still remains elusive, as the possibility of H1 variants having distinct roles in a cell-specific manner. Here, we map the genomic localization of several H1 variants in cervical cancer cells, specifically HeLa-S3 cell line by using chromatin immunoprecipitation followed by massively parallel sequencing (ChIP-seq) in wild type and HA-tagged engineered cell lines. In short, our work integrates the genomic distribution at promoters, genome-wide and important genomic features. In addition, we present a cytogenetic band classification model by which we prove variant-specific location as well as new insights about the potential dual behaviour of H1X variant along the genome.