Kinesin-4 Functions in Vesicular Transport on Cortical Microtubules and Regulates Cell Wall Mechanics during Cell Elongation in Plants
Kinesin-4 Functions in Vesicular Transport on Cortical Microtubules and Regulates Cell Wall Mechanics during Cell Elongation in Plants
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Kinesin-4 在皮质微管上的囊泡运输中发挥作用，并在植物细胞伸长过程中调节细胞壁力学
DOI：
10.1016/j.molp.2015.01.004
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发表时间：
2015-07-06
期刊：
影响因子：
27.5
通讯作者：
Liu, Bo
中科院分区：
文献类型：
--
作者：
Kong, Zhaosheng;Ioki, Motohide;Liu, Bo
在植物中，各向异性的细胞扩张依赖于皮层微管，微管作为大分子和囊泡被未知身份的运动驱动蛋白运输的沿着。我们使用棉花（陆地棉）纤维，经历了强大的伸长，发现驱动蛋白参与细胞伸长，并发现Gh KINESIN-4A表达丰富。通过免疫荧光检测与皮质微管相关的囊泡样结构的电机。在拟南芥中，正交电机在KINESIN-4A/FRA 1，以前牵连在纤维细胞的二次生长过程中的纤维素沉积，在细胞中表达荧光标记的功能蛋白的活细胞成像检查。马达装饰囊泡样颗粒，表现出线性运动沿着皮层微管的平均速度为0.89 mm/min，这是显着不同的那些与纤维素生物合成。我们还发现，At KINESIN-4A/FRA 1和相关的At KINESIN-4C在细胞壁力学、细胞伸长以及各种营养和生殖器官的轴向生长中发挥冗余作用，因为At KINESIN-4C的缺失极大地增强了由KINESIN-4A/FRA 1基因座处的无效突变引起的缺陷。双突变体在细胞快速伸长的正常阶段显示缺乏细胞壁软化。此外，在驱动蛋白-4突变体中检测到含阿拉伯糖的碳水化合物的沉积增强。我们的研究结果建立了基于驱动蛋白-4的货物含有非纤维素成分沿着皮层微管和细胞壁力学和细胞伸长在开花植物之间的连接。
In plants, anisotropic cell expansion depends on cortical microtubules that serve as tracks along which macromolecules and vesicles are transported by the motor kinesins of unknown identities. We used cotton (Gossypium hirsutum) fibers that underwent robust elongation to discover kinesins that are involved in cell elongation and found Gh KINESIN-4A expressed abundantly. The motor was detected by immunofluorescence on vesicle-like structures that were associated with cortical microtubules. In Arabidopsis thaliana, the orthologous motor At KINESIN-4A/FRA1, previously implicated in cellulose deposition during secondary growth in fiber cells, was examined by live-cell imaging in cells expressing the fluorescently tagged functional protein. The motor decorated vesicle-like particles that exhibit a linear movement along cortical microtubules with an average velocity of 0.89 mm/min, which was significantly different from those linked to cellulose biosynthesis. We also discovered that At KINESIN-4A/FRA1 and the related At KINESIN-4C play redundant roles in cell wall mechanics, cell elongation, and the axial growth of various vegetative and reproductive organs, as the loss of At KINESIN-4C greatly enhanced the defects caused by a null mutation at the KINESIN-4A/FRA1 locus. The double mutant displayed a lack of cell wall softening at normal stages of rapid cell elongation. Furthermore, enhanced deposition of arabinose-containing carbohydrate was detected in the kinesin-4 mutants. Our findings established a connection between the Kinesin-4-based transport of cargoes containing non-cellulosic components along cortical microtubules and cell wall mechanics and cell elongation in flowering plants.