Please use this identifier to cite or link to this item: https://hdl.handle.net/20.500.12530/30538
Title: A right-handed signalling pathway drives heart looping in vertebrates.
Authors: 
Mesh: 
Issue Date: 2017
Citation: Nature.2017 09;(549)7670:86-90
Abstract: Most animals show external bilateral symmetry, which hinders the observation of multiple internal left-right (L/R) asymmetries that are fundamental to organ packaging and function. In vertebrates, left identity is mediated by the left-specific Nodal-Pitx2 axis that is repressed on the right-hand side by the epithelial-mesenchymal transition (EMT) inducer Snail1 (refs 3, 4). Despite some existing evidence, it remains unclear whether an equivalent instructive pathway provides right-hand-specific information to the embryo. Here we show that, in zebrafish, BMP mediates the L/R asymmetric activation of another EMT inducer, Prrx1a, in the lateral plate mesoderm with higher levels on the right. Prrx1a drives L/R differential cell movements towards the midline, leading to a leftward displacement of the cardiac posterior pole through an actomyosin-dependent mechanism. Downregulation of Prrx1a prevents heart looping and leads to mesocardia. Two parallel and mutually repressed pathways, respectively driven by Nodal and BMP on the left and right lateral plate mesoderm, converge on the asymmetric activation of the transcription factors Pitx2 and Prrx1, which integrate left and right information to govern heart morphogenesis. This mechanism is conserved in the chicken embryo, and in the mouse SNAIL1 acts in a similar manner to Prrx1a in zebrafish and PRRX1 in the chick. Thus, a differential L/R EMT produces asymmetric cell movements and forces, more prominent from the right, that drive heart laterality in vertebrates.
PMID: 28880281
URI: https://hdl.handle.net/20.500.12530/30538
Rights: openAccess
Appears in Collections:Fundaciones e Institutos de Investigación > IIS H. U. Ramón y Cajal > Artículos

Files in This Item:
File Description SizeFormat 
PMC5590727.pdf8.51 MBAdobe PDFThumbnail
View/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.