During Embryogenesis, Esrp1 Expression Is Restricted to a Subset of Epithelial Cells and Is Associated With Splicing of a Number of Developmentally Important Genes

Abstract

Background: Development of a mature organism from a single cell requires a series of important morphological changes, which is in part regulated by alternative splicing. In this article, we report the expression of Esrp1 during early mouse embryogenesis, a splicing factor implicated in epithelial to mesenchymal transitions. Results: By qRT-PCR, we find higher expression of Esrp1 and Esrp2 in placenta compared to the embryos. We also find a correlation between the expression of Esrp1 and alternative splicing of several known target exons. Using in situ RNA hybridization we show that while Esrp1 expression is ubiquitous in embryonic day (E)6.5 mouse embryos, expression becomes restricted to the chorion and definitive endoderm starting at E7.5. Esrp1 expression was consistently restricted to a subset of epithelial cell types in developing embryos from E9.5 to E13.5. Conclusions: Our results suggest that Esrp1 could play an important role in the morphological changes underlying embryogenesis of the placenta and embryo. Developmental Dynamics 242:281-290, 2013. © 2012 Wiley Periodicals, Inc. Key Findings: The splicing factors Esrp1 and Esrp2 are differentially expressed in a time- and tissue-dependent manner during mouse embryogenesis. The expression of Esrp1 correlates with the alternative splicing of Cask-1, Dock-7 and Osbpl3. Using in situ RNA hybridization, we show that expression of Esrp1 is ubiquitous in E6.5 embryos, then becomes restricted to the chorion and definitive endoderm at E7.5. Esrp1 expression is restricted in a subset of epithelial cell types in later staged mouse embryos. © 2012 Wiley Periodicals, Inc.