Knockout of the AtCESA2 gene affects microtubule orientation and causes abnormal cell expansion in Arabidopsis
Knockout of the AtCESA2 gene affects microtubule orientation and causes abnormal cell expansion in Arabidopsis
复制标题
AtCESA2 基因的敲除会影响拟南芥中的微管方向并导致细胞异常扩增
DOI：
10.1104/pp.106.088393
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发表时间：
2007-01-01
期刊：
影响因子：
7.4
通讯作者：
Xie, Qi
中科院分区：
文献类型：
--
作者：
Chu, Zhaoqing;Chen, Hao;Xie, Qi
完整的纤维素合成是形成功能性细胞壁和促进植物生长过程中适当的细胞扩张所必需的。AtCESA 2是拟南芥（Arabidopsis thaliana）中参与细胞壁形成的纤维素合成酶A家族的成员。通过对转基因幼苗的分析，我们证明AtCESA 2在除根毛外的所有器官中表达。atcesa2突变体缺乏AtCESA2表达，导致幼苗下胚轴生长发育不良，并大大降低成熟植物的种子产量。这些观察结果归因于突变体中纤维素合成减少导致的细胞大小的改变。atcesa2突变体中微管的方向也发生了改变，这在下胚轴和叶柄中明显观察到。在atcesa2中互补表达AtCESA 2可以挽救突变表型。总之，我们得出结论，纤维素合成的中断导致微管方向的改变，并最终导致植物生长异常。我们还证明了AtCESA 2的锌指样结构域可以同源二聚化，可能有助于质膜内纤维素合酶A的玫瑰花结组装。
Complete cellulose synthesis is required to form functional cell walls and to facilitate proper cell expansion during plant growth. AtCESA2 is a member of the cellulose synthase A family in Arabidopsis (dArabidopsis thaliana) that participates in cell wall formation. By analysis of transgenic seedlings, we demonstrated that AtCESA2 was expressed in all organs, except root hairs. The atcesa2 mutant was devoid of AtCESA2 expression, leading to the stunted growth of hypocotyls in seedlings and greatly reduced seed production in mature plants. These observations were attributed to alterations in cell size as a result of reduced cellulose synthesis in the mutant. The orientation of microtubules was also altered in the atcesa2 mutant, which was clearly observed in hypocotyls and petioles. Complementary expression of AtCESA2 in atcesa2 could rescue the mutant phenotypes. Together, we conclude that disruption of cellulose synthesis results in altered orientation of microtubules and eventually leads to abnormal plant growth. We also demonstrated that the zinc finger-like domain of AtCESA2 could homodimerize, possibly contributing to rosette assemblies of cellulose synthase A within plasma membranes.