拟南芥根冠细胞中的纵向分裂

Longitudinal Divisions in Root Cap Cells of Arabidopsis Primary Roots

摘要: 拟南芥根冠中的细胞分裂被认为受到严格的调控。一般认为柱干细胞只进行水平方向的分裂，且在时间上高度同步，由此产生排列规则的柱细胞层，而侧根冠干细胞的分裂方向与柱干细胞的分裂方向相差约90度，其子细胞则以水平方向分裂为主。本研究中，我们通过对根冠区横切片的观察，发现在野生型幼苗根中柱干细胞，柱细胞均和侧根冠细胞均可进行纵向分裂。同时还观察到柱干细胞膨大挤压外围柱细胞圈的现象，但对其正常的功能以及根冠的结构无明显影响。本研究的结果为进一步研究拟南芥根冠细胞的分裂调控奠定了一定的基础。

Abstract: Cell division in Arabidopsis root cap is thought to be strictly regulated. It is generally believed that columella stem cells only divide horizontally and are highly synchronized in time, resulting in well organized cell layers. The division orientation of lateral root cap stem cells is about 90 degrees to that of columella stem cells, and their daughter cells mainly divide horizontally. In this study, we found longitudinal divisions in the collumella stem cells, collumella cells and lateral root cap cells of the primary roots of wild-type seedlings. In addition, we also observed a phenomenon that a columella stem cell in the central region expanded abnormally into and squeezed the outer layer of columella stem cells, but did not have an obvious impact on either the normal function of columella stem cells or the overall cellular structure of the root cap. The results of this study laid a foundation for further study on the regulation of root cap cell division in Arabidopsis.