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bioRxiv · 10.1101/129056

An Embryonic System To Assess Wnt Transcriptional Targets

Suresh, J.·Harmston, N.·Lim, K. K.·Kaur, P.·Jin, H. J.·Lusk, J. B.·Petretto, E.·Tolwinski, N. S.
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Abstract

During animal development, complex signals determine and organize a vast number of tissues using a very small number of signal transduction pathways. These developmental signaling pathways determine cell fates through a coordinated transcriptional response that remains poorly understood. The Wnt pathway is involved in a variety of these cellular functions, and its signals are transmitted in part through a {beta}-catenin/TCF transcriptional complex. Here we report an in vivo Drosophila assay that can be used to distinguish between activation, de-repression and repression of transcriptional responses, separating upstream and downstream pathway activation and canonical/non-canonical Wnt signals in embryos. We find specific sets of genes downstream of both {beta}-catenin and TCF with an additional group of genes regulated by Wnt, while the non-canonical Wnt4 regulates a separate cohort of genes. We correlate transcriptional changes with phenotypic outcomes of cell differentiation and embryo size, showing our model can be used to characterize developmental signaling compartmentalization in vivo.

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Suresh, J., Harmston, N., Lim, K. K., Kaur, P., Jin, H. J., Lusk, J. B., Petretto, E., Tolwinski, N. S.. 2017-04-21. An Embryonic System To Assess Wnt Transcriptional Targets. https://doi.org/10.1101/129056

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