Okabe Noriko, Xu Bo, Burdine Rebecca D
Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA.
Dev Dyn. 2008 Dec;237(12):3602-12. doi: 10.1002/dvdy.21730.
Work in mouse has implicated cilia motility and leftward nodal flow as the mechanism for breaking left-right symmetry. In zebrafish, it is assumed that Kupffer's vesicle is analogous to the mouse node. However, its architecture is different and the fluid dynamics inside Kupffer's vesicle is not completely understood. We show that cells lining both the dorsal roof and the ventral floor of Kupffer's vesicle possess posteriorly pointed cilia that rotate clockwise when viewed apically. Analysis of bead movements within Kupffer's vesicle shows a net circular flow but the local flow differs in direction depending on the location within the vesicle. Histological analysis suggests that the orientation of the cells at anterior-dorsal region likely direct net flow in the vesicle. Our data suggest that the plane of the circular net flow is tilted with respect to the D-V axis, which may be converted to a local leftward flow in the anterior-dorsal region of the vesicle.
在小鼠中的研究表明，纤毛运动和向左的节点流是打破左右对称的机制。在斑马鱼中，人们认为库普弗小泡类似于小鼠的节点。然而，它的结构不同，库普弗小泡内的流体动力学也尚未完全了解。我们发现，库普弗小泡背顶和腹底的细胞都具有向后尖的纤毛，从顶端观察时这些纤毛顺时针旋转。对库普弗小泡内珠子运动的分析显示有净循环流，但局部流的方向因小泡内位置的不同而不同。组织学分析表明，前背区域细胞的取向可能引导小泡内的净流。我们的数据表明，循环净流平面相对于背腹轴倾斜，这可能在小泡的前背区域转化为局部向左的流。
