TY - JOUR T1 - GA-repeats on mammalian X chromosomes support Ohno’s hypothesis of dosage compensation by transcriptional upregulation JF - bioRxiv DO - 10.1101/485300 SP - 485300 AU - Edridge D’Souza AU - Elizaveta Hosage AU - Kathryn Weinand AU - Steve Gisselbrecht AU - Vicky Markstein AU - Peter Markstein AU - Martha L. Bulyk AU - Michele Markstein Y1 - 2018/01/01 UR - http://biorxiv.org/content/early/2018/12/04/485300.abstract N2 - Over 50 years ago, Susumo Ohno proposed that dosage compensation in mammals would require upregulation of gene expression on the single active X chromosome, a mechanism which to date is best understood in the fruit fly Drosophila melanogaster. Here, we report that the GA-repeat sequences that recruit the conserved MSL dosage compensation complex to the Drosophila X chromosome are also enriched across mammalian X chromosomes, providing genomic support for the Ohno hypothesis. We show that mammalian GA-repeats derive in part from transposable elements, suggesting a mechanism whereby unrelated X chromosomes from dipterans to mammals accumulate binding sites for the MSL dosage compensation complex through convergent evolution, driven by their propensity to accumulate transposable elements. ER -