Abstract
Wnt signalling has several roles during heart development, which involve both inhibition of cardiogenesis by canonical Wnt/ß-catenin signaling and stimulation by non-canonical Wnt11/JNK signaling. Here, we use stem-cell-like embryonic explants from Xenopus laevis to investigate the timing of Wnt molecules function and the molecular basis of the regulatory mechanisms involved. We uncover a central role for GATA transcription factors in integrating and regulating Wnt signaling in cardiogenesis. GATA gene expression emerges as the relevant target for inhibition by canonical Wnt/ ß-catenin signaling, since experimentally reinstating GATA function overrides ß-catenin–mediated inhibition and restores cardiogenesis. GATA transcription factors in turn directly regulate not only Nkx2-5 but also Wnt11. We show that Wnt11 function is indeed required to a large extent for mediating the cardiogenesis-promoting activity of GATA transcription factors. These results demonstrate that GATA transcription factors occupy a central position between canonical and non-canonical Wnt signaling in a pathway regulating heart muscle differentiation.
Original language | English |
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Pages (from-to) | S227 |
Number of pages | 1 |
Journal | Mechanisms of Development |
Volume | 126 |
Issue number | Supplement |
DOIs | |
Publication status | Published - Aug 2009 |