A katanin-like protein regulates normal cell wall biosynthesis and cell elongation
A katanin-like protein regulates normal cell wall biosynthesis and cell elongation
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DOI：
10.1105/tpc.13.4.807
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发表时间：
2001-04-01
期刊：
影响因子：
11.6
通讯作者：
Ye, ZH
中科院分区：
文献类型：
--
作者：
Burk, DH;Liu, B;Ye, ZH
纤维是为植物体提供结构支撑的机械组织之一。为了了解如何正常的机械强度的纤维进行调节，我们分离出拟南芥脆弱的纤维（FRA2）突变体的机械强度的束间纤维在花序茎缺陷。解剖和化学分析表明，fra2突变导致纤维细胞长度和壁厚减少，纤维素和半纤维素含量减少，木质素缩合增加，表明fra2的脆性纤维表型是纤维细胞伸长和细胞壁生物合成改变的结果。FRA 2突变导致所有器官中细胞长度的显著减少和细胞宽度的增加，这导致植物形态的全面改变。FRA2基因被证明编码一种与katanin高度相似的蛋白质（因此FRA2被重新命名为AtKTN 1），一种通过切断微管参与调节微管分解的蛋白质。与AtKTN 1作为微管切断蛋白的假定功能一致，免疫定位表明，Fra2突变导致核周微管阵列消失延迟，并在间期和延长细胞中建立横向皮质微管阵列。总之，这些结果表明，AtKTN1，katanin样蛋白，是必不可少的，不仅正常的细胞壁生物合成和纤维细胞的细胞伸长，但也在所有器官的细胞扩增。
Fibers are one of the mechanical tissues that provide structural support to the plant body. To understand how the normal mechanical strength of fibers is regulated, we isolated an Arabidopsis fragile fiber (fra2) mutant defective in the mechanical strength of interfascicular fibers in the inflorescence stems. Anatomical and chemical analyses showed that the fra2 mutation caused a reduction in fiber cell length and wall thickness, a decrease in cellulose and hemicellulose contents, and an increase in lignin condensation, indicating that the fragile fiber phenotype of fra2 is a result of alterations in fiber cell elongation and cell wail biosynthesis, In addition to the effects on fibers, the fra2 mutation resulted in a remarkable reduction in cell length and an increase in cell width in all organs, which led to a global alteration in plant morphology. The FRA2 gene was shown to encode a protein with high similarity to katanin (hence FRA2 was renamed AtKTN1), a protein shown to be involved in regulating microtubule disassembly by severing microtubules. Consistent with the putative function of AtKTN1 as a microtubule-severing protein, immunolocalization demonstrated that the fra2 mutation caused delays in the disappearance of perinuclear microtubule array and in the establishment of transverse cortical microtubule array in interphase and elongating cells. Together, these results suggest that AtKTN1, a katanin-like protein, is essential not only for normal cell wall biosynthesis and cell elongation in fiber cells but also for cell expansion in all organs.