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The mammalian decidual cell evolved from a cellular stress response
Citation: Erkenbrack, E. M., Maziarz, J., Griffith, O. W., Liang, C., Chavan, A. R., Nnamani, M., & Wagner, G. P. (2016). The mammalian decidual cell evolved from a cellular stress response. PLOS Biol 16(8): e2005594.
Among animal species, cell types vary greatly in terms of number and kind. The number of
cell types found within an organism differs considerably between species, and cell type
diversity is a significant contributor to differences in organismal structure and function.
These observations suggest that cell type origination is a significant source of evolutionary
novelty. The molecular mechanisms that result in the evolution of novel cell types, however,
are poorly understood. Here, we show that a novel cell type of eutherians mammals, the
decidual stromal cell (DSC), evolved by rewiring an ancestral cellular stress response. We
isolated the precursor cell type of DSCs, endometrial stromal fibroblasts (ESFs), from the
opossum Monodelphis domestica. We show that, in opossum ESFs, the majority of decidual
core regulatory genes respond to decidualizing signals but do not regulate decidual effector
genes. Rather, in opossum ESFs, decidual transcription factors function in apoptotic and
oxidative stress response. We propose that the rewiring of cellular stress responses was an
important mechanism for the evolution of eutherian decidual cell type.

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© 2018 Eric M Erkenbrack et al. All rights reserved.