Authors: Koustav Pal, Mattia Forcato, Daniel Jost, Thomas Sexton, Cédric Vaillant, Elisa Salviato, Emilia Maria Cristina Mazza, Enrico Lugli, Giacomo Cavalli, Francesco Ferrari
Published: 2019-11-25
DOI: 10.1038/s41467-019-13350-8
Source: Full article
AbstractIn Drosophila melanogaster the single male chromosome X undergoes an average twofold transcriptional upregulation for balancing the transcriptional output between sexes. Previous literature hypothesised that a global change in chromosome structure may accompany this process. However, recent studies based on Hi-C failed to detect these differences. Here we show that global conformational differences are specifically present in the male chromosome X and detectable using Hi-C data on sex-sorted embryos, as well as male and female cell lines, by leveraging custom data analysis solutions. We find the male chromosome X has more mid-/long-range interactions. We also identify differences at structural domain boundaries containing BEAF-32 in conjunction with CP190 or Chromator. Weakening of these domain boundaries in male chromosome X co-localizes with the binding of the dosage compensation complex and its co-factor CLAMP, reported to enhance chromatin accessibility. Together, our data strongly indicate that chromosome X dosage compensation affects global chromosome structure.