Dynamic Sex Chromosome Expression in Drosophila Male Germ Cells

Mahadevaraju, S.; Fear, J. M.; Akeju, M.; Galletta, B. J.; Pinheiro, M. M.; Avelino, C. C.; Cabral-de-Mello, D. C.; Conlon, K.; Dell'Orso, S.; Demere, Z.; Mansuria, K.; Mendonca, C. A.; Palacios-Gimenez, O. M.; Ross, E.; Savery, M.; Yu, K.; Smith, H. E.; Sartorelli, V.; Rusan, N. M.; Vibranovski, M. D.; Matunis, E.; Oliver, B.

doi:10.1101/2020.03.23.000356

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bioRxiv · 10.1101/2020.03.23.000356

Dynamic Sex Chromosome Expression in Drosophila Male Germ Cells

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Abstract

Sex chromosome gene content and expression is unusual. In many organisms the X and Y chromosomes are inactivated in spermatocytes, possibly as a defense mechanism against insertions into unpaired chromatin. In addition to current sex chromosomes, Drosophila has a small gene-poor X-chromosome relic (4th) that re-acquired autosomal status. Using single cell RNA-Seq, we demonstrate that the single X and pair of 4th chromosomes are specifically inactivated in primary spermatocytes. In contrast, genes on the single Y chromosome become maximally active in primary spermatocytes. Reduced X steady-state transcript levels are due to failed activation of RNA-Polymerase-II by phosphorylation of Serine 2 and 5. One Sentence SummarySex chromosome expression during spermatogenesis at the single cell level

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Mahadevaraju, S., Fear, J. M., Akeju, M., Galletta, B. J., Pinheiro, M. M., Avelino, C. C., Cabral-de-Mello, D. C., Conlon, K., Dell'Orso, S., Demere, Z., Mansuria, K., Mendonca, C. A., Palacios-Gimenez, O. M., Ross, E., Savery, M., Yu, K., Smith, H. E., Sartorelli, V., Rusan, N. M., Vibranovski, M. D., Matunis, E., Oliver, B.. 2020-03-23. Dynamic Sex Chromosome Expression in Drosophila Male Germ Cells. https://doi.org/10.1101/2020.03.23.000356

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