PT  - JOURNAL ARTICLE
AU  - D’Souza, Edridge
AU  - Hosage, Elizaveta
AU  - Weinand, Kathryn
AU  - Gisselbrecht, Steve
AU  - Markstein, Vicky
AU  - Markstein, Peter
AU  - Bulyk, Martha L.
AU  - Markstein, Michele
TI  - GA-repeats on mammalian X chromosomes support Ohno’s hypothesis of dosage compensation by transcriptional upregulation
AID  - 10.1101/485300
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 485300
4099  - http://biorxiv.org/content/early/2018/12/04/485300.short
4100  - http://biorxiv.org/content/early/2018/12/04/485300.full
AB  - 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.