Role of the Gut Endoderm in Relaying Left-Right Patterning in Mice
Figure 8
Working model for role of gut endoderm in LR asymmetry establishment.
Sox17 regulates morphogenesis of the gut endoderm, whose cellular interfaces contain Cx43-comprised gap junctions. After LR symmetry is broken in the node by rotating cilia, the resulting nodal flow induces left-biased asymmetries around the node. These asymmetries are transmitted via gap junction communication within the gut endoderm to the target tissue, the left LPM, where the Nodal/Lefty2/Pitx2 asymmetry cascade is activated.