| First Author | Takao D | Year | 2013 |
| Journal | Dev Biol | Volume | 376 |
| Issue | 1 | Pages | 23-30 |
| PubMed ID | 23357539 | Mgi Jnum | J:195164 |
| Mgi Id | MGI:5476602 | Doi | 10.1016/j.ydbio.2013.01.018 |
| Citation | Takao D, et al. (2013) Asymmetric distribution of dynamic calcium signals in the node of mouse embryo during left-right axis formation. Dev Biol 376(1):23-30 |
| abstractText | In the node of mouse embryo, rotational movements of cilia generate an external liquid flow known as nodal flow, which determines left-right asymmetric gene expression. How nodal flow is converted into asymmetric gene expression is still controversial, but the increase of Ca(2+) levels in endodermal cells to the left of the node has been proposed to play a role. However, Ca(2+) signals inside the node itself have not yet been described. By our optimized Ca(2+) imaging method, we were able to observe dynamic Ca(2+) signals in the node in live mouse embryos. Pharmacological disruption of Ca(2+) signals did not affect ciliary movements or nodal flow, but did alter the expression patterns of the Nodal and Cerl-2 genes. Quantitative analyses of Ca(2+) signal frequencies and distributions showed that during left-right axis establishment, formerly symmetric Ca(2+) signals became biased to the left side. In iv/iv mutant embryos that showed randomized laterality due to ciliary immotility, Ca(2+) signals were found to be variously left-sided, right-sided, or bilateral, and thus symmetric on average. In Pkd2 mutant embryos, which lacked polycystin-2, a Ca(2+)-permeable cation channel necessary for left-right axis formation, the Ca(2+) signal frequency was lower than in wild-type embryos. Our data support a model in which dynamic Ca(2+) signals in the node are involved in left-right patterning. |
