The mammalian decidual cell evolved from a cellular stress response

Area of Science:

• Evolutionary biology
• Developmental biology
• Cellular and molecular biology

Background:

• Cell type diversity significantly impacts organismal structure and function across species.
• The evolutionary origins of novel cell types are not well understood at the molecular level.

Purpose of the Study:

• To investigate the molecular mechanisms behind the evolution of the eutherian decidual stromal cell (DSC).
• To explore the role of ancestral cellular stress responses in the emergence of new cell types.

Main Methods:

• Isolation of endometrial stromal fibroblasts (ESFs) from the opossum Monodelphis domestica as the precursor cell type.
• Analysis of the function of decidual core regulatory genes in opossum ESFs.
• Comparison of gene regulation in response to decidualizing signals versus stress responses.

Main Results:

• In opossum ESFs, decidual transcription factors primarily function in apoptotic and oxidative stress responses, not in regulating decidual effector genes.
• Decidual core regulatory genes in ESFs respond to decidualizing signals but do not control downstream decidual genes.

Conclusions:

• The evolution of the eutherian decidual cell type likely involved the rewiring of ancestral cellular stress response pathways.
• Rewiring of stress responses represents a key mechanism for generating evolutionary novelty through cell type origination.