A Sprouty4 reporter to monitor FGF/ERK signaling activity in ESCs and mice

作者：Morgani Sophie M; Saiz Nestor; Garg Vidur; Raina Dhruv; Simon Claire S; Kang Minjung; Arias Alfonso Martinez; Nichols Jennifer; Schroeter Christian; Hadjantonakis Anna Katerina^*

来源：Developmental Biology, 2018, 441(1): 104-126.

DOI：10.1016/j.ydbio.2018.06.017

• Sprouty4
• FGF/ERIC
• FGF signaling
• ESCs
• Mouse embryo
• Fluorescent reporter
• Live imaging
• Quantitative image analysis

The FGF/ERK signaling pathway is highly conserved throughout evolution and plays fundamental roles during embryonic development and in adult organisms. While a plethora of expression data exists for ligands, receptors and pathway regulators, we know little about the spatial organization or dynamics of signaling in individual cells within populations. To this end we developed a transcriptional readout of FGF/ERK activity by targeting a histone H2B-linked Venus fluorophore to the endogenous locus of Spry4, an early pathway target, and generated Spry4(H2B-venus) embryonic stem cells (ESCs) and a derivative mouse line. The Spry4(H2B-venus) reporter was heterogeneously expressed within ESC cultures and responded to FGF/ERK signaling manipulation. In vivo, the Spry4(H2B-venus) reporter recapitulated the expression pattern of Spry4 and localized to sites of known FGF/ERIC activity including the inner cell mass of the pre-implantation embryo and the limb buds, somites and isthmus of the post-implantation embryo. Additionally, we observed highly localized reporter expression within adult organs. Genetic and chemical disruption of FGF/ERK signaling, in vivo in pre- and post-implantation embryos, abrogated Venus expression establishing the reporter as an accurate signaling readout. This tool will provide new insights into the dynamics of the FGF/ERK signaling pathway during mammalian development.

• 出版日期2018-9-1