COBRA encodes a putative GPI-anchored protein, which is polarly localized and necessary for oriented cell expansion in Arabidopsis
COBRA encodes a putative GPI-anchored protein, which is polarly localized and necessary for oriented cell expansion in Arabidopsis
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DOI：
10.1101/gad.879101
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发表时间：
2001-05-01
影响因子：
10.5
通讯作者：
Benfey, PN
中科院分区：
文献类型：
--
作者：
Schindelman, G;Morikami, A;Benfey, PN
为了控制器官形状，植物细胞有差异地扩张。细胞壁中纤维素微纤维的组织是差异膨胀的关键决定因素。据报道，拟南芥 COBRA (COB) 基因的突变会影响根部细胞扩张的方向，从而减少根部生长区细胞壁中结晶纤维素的含量。通过基于图谱的克隆鉴定出的 COB 基因包含在蛋白质中发现的序列基序，这些蛋白质通过糖基磷脂酰肌醇 (GPI) 连接锚定在质膜的细胞外表面。在动物细胞中，已知这种脂质连接赋予蛋白质极性定位。 COB 蛋白主要在快速伸长区根细胞的纵向侧检测到。此外，在进入快速伸长区的细胞中，COB RNA 水平显着上调。基于这些结果，提出了 COB 作为定向细胞扩增调节剂作用的模型。
To control organ shape, plant cells expand differentially. The organization of the cellulose microfibrils in the cell wall is a key determinant of differential expansion. Mutations in the COBRA (COB) gene of Arabidopsis, known to affect the orientation of cell expansion in the root, are reported here to reduce the amount of crystalline cellulose in cell walls in the root growth zone. The COB gene, identified by map-based cloning, contains a sequence motif found in proteins that are anchored to the extracellular surface of the plasma membrane through a glycosylphosphatidylinositol (GPI) linkage. In animal cells, this lipid linkage is known to confer polar localization to proteins. The COB protein was detected predominately on the longitudinal sides of root cells in the zone of rapid elongation Moreover, COB RNA levels are dramatically upregulated in cells entering the zone of rapid elongation. Based on these results, models are proposed for the role of COB as a regulator of oriented cell expansion.