Abstract
During the embryonic developmental stage in vertebrates, internal organs are arranged along the left-right axis. Disruptions in this process can result in congenital diseases or laterality disorders. The molecular mechanisms of left-right asymmetry in vertebrate development remain largely unclear. Due to its straightforward structure, zebrafish has become a favoured model for studying early laterality events. Here, we demonstrate that growth and development factor 11 (Gdf11) is essential for left-right development via TGF-β signalling. Morphological analysis showed that gdf11 morphants and mutants displayed clear heart and liver laterality disorders in a Nodal signal-dependent manner. Additionally, we found that Kupffer's vesicle formation and ciliogenesis were impaired following gdf11 deletion. We also observed that Gdf11 may form a heterodimer with Spaw, which promotes Smad2/3 phosphorylation and activates TGF-β signalling. Subsequently, Gdf11 promotes left-right laterality by stimulating Foxj1a and its target gene expression. In summary, we reveal a critical role of Gdf11 in left-right patterning, providing fundamental insights into the developmental process of left-right asymmetry.