Evolutionary recruitment of flexible Esrp-dependent splicing programs into diverse embryonic morphogenetic processes

Area of Science:

• Developmental Biology
• Evolutionary Biology
• Molecular Biology

Background:

• Epithelial-mesenchymal interactions are fundamental to animal structure development.
• Understanding molecular mechanisms controlling these interactions is key to morphogenetic evolution.
• Esrp genes orchestrate splicing programs vital for mammalian organogenesis.

Purpose of the Study:

• To investigate the evolutionary recruitment and roles of Esrp homologs in deuterostome development.
• To identify ancient functions of Esrp genes in non-neural ectoderm and mesenchymal-to-epithelial transitions.
• To understand how Esrp-dependent splicing programs were rewired during vertebrate evolution.

Main Methods:

• Comparative genomics analysis of Esrp homologs across deuterostomes.
• Analysis of Esrp gene function in various developmental processes.
• Investigating the relationship between Esrp and Fgfr in chordate and vertebrate evolution.

Main Results:

• Esrp homologs show independent recruitment for diverse structures across deuterostomes.
• Ancient roles for Esrp in non-neural ectoderm and mesenchymal-to-epithelial transitions are suggested.
• Vertebrate developmental defects often involve processes distinct from ancestral Esrp functions, linked to Fgfr co-option.

Conclusions:

• Esrp genes have a conserved ancient role in deuterostome development, particularly in ectodermal and mesenchymal-epithelial transitions.
• Evolutionary rewiring of Esrp-dependent splicing, including Fgfr recruitment, facilitated novel trait development in vertebrates.
• This highlights the plasticity of gene regulatory networks in shaping evolutionary trajectories.