Poster Presentation Society for Molecular Biology and Evolution Conference 2016

Evidence for post-transcriptional regulation of dosage compensation in platypus (#461)

William B Horspool 1 , Carly Conlan 2 , Paul D Waters 1
  1. School of Biotechnology and Biomolecular Sciences, University Of New South Wales, Sydney, NSW, Australia
  2. Australian National University, Canberra, ACT, Australia

In mammals males have a single X chromosome, whereas females have two. A dosage compensation system was thought to have evolved to increase gene expression from the single X in males to the equivalent of two Xs. This system was assumed to be essential to survival, but within vertebrates many examples of partial or incomplete dosage compensation challenge this view. For example, in platypus, expression from the Xs is heavily female biased. All previous large scale studies of dosage compensation have focused on total RNA transcript levels. In this study RNA-seq, polysome fractionation and iTRAQ was used to analyse platypus and opossum dosage compensation at different stages from the genome to the proteome. For the first time this analysis demonstrates that post transcriptional dosage compensation might be occurring in platypus, a species previously thought to have an ineffective dosage compensation system. This has large implications for inconsistencies observed in the dosage compensation systems of other species.