Wu Mingfu, Herman Michael A
Program in Molecular, Cellular and Developmental Biology, Division of Biology, Kansas State University, Manhattan, KS 66506, USA.
Dev Biol. 2006 May 15;293(2):316-29. doi: 10.1016/j.ydbio.2005.12.024. Epub 2006 Apr 24.
The polarities of several cells that divide asymmetrically during Caenorhabditis elegans development are controlled by Wnt signaling. LIN-44/Wnt and LIN-17/Fz control the polarities of cells in the tail of developing C. elegans larvae, including the male-specific blast cell, B, that divides asymmetrically to generate a larger anterior daughter and a smaller posterior daughter. We determined that WRM-1 and the major canonical Wnt pathway components: BAR-1, SGG-1/GSK-3 and PRY-1/Axin were not involved in the control of B cell polarity. However, POP-1/Tcf is involved and is asymmetrically distributed to the B daughter nuclei, as it is in many cell divisions during C. elegans development. Aspects of the B cell division are reminiscent of the divisions controlled by the planar cell polarity (PCP) pathway that has been described in both Drosophila and vertebrate systems. We identified C. elegans homologs of Wnt/PCP signaling components and have determined that many of them appear to be involved in the regulation of B cell polarity. Specifically, MIG-5/Dsh, RHO-1/RhoA and LET-502/ROCK appear to play major roles, while other PCP components appear to play minor roles. We conclude that a noncanonical Wnt pathway, which is different from other Wnt pathways in C. elegans, regulates B cell polarity.
在秀丽隐杆线虫发育过程中，几个进行不对称分裂的细胞的极性受Wnt信号通路控制。LIN-44/Wnt和LIN-17/Fz控制着发育中的秀丽隐杆线虫幼虫尾部细胞的极性，包括雄性特异性胚细胞B，它进行不对称分裂，产生一个较大的前子代细胞和一个较小的后子代细胞。我们确定WRM-1以及主要的经典Wnt信号通路成分：BAR-1、SGG-1/GSK-3和PRY-1/Axin不参与B细胞极性的控制。然而，POP-1/Tcf参与其中，并像在秀丽隐杆线虫发育过程中的许多细胞分裂一样，不对称地分布到B子代细胞核中。B细胞分裂的某些方面让人联想到果蝇和脊椎动物系统中所描述的由平面细胞极性（PCP）信号通路控制的分裂。我们鉴定出了Wnt/PCP信号成分的秀丽隐杆线虫同源物，并确定其中许多似乎参与了B细胞极性的调节。具体而言，MIG-5/Dsh、RHO-1/RhoA和LET-502/ROCK似乎起主要作用，而其他PCP成分似乎起次要作用。我们得出结论，一种不同于秀丽隐杆线虫中其他Wnt信号通路的非经典Wnt信号通路调节B细胞极性。
