Validation of microtubule-associated Tobacco mosaic virus RNA movement and involvement of microtubule-aligned particle trafficking
Validation of microtubule-associated Tobacco mosaic virus RNA movement and involvement of microtubule-aligned particle trafficking
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DOI：
10.1111/j.1365-313x.2007.03163.x
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发表时间：
2007-08-01
期刊：
影响因子：
7.2
通讯作者：
Heinlein, Manfred
中科院分区：
文献类型：
--
作者：
Boyko, Vitaly;Hu, Quanan;Heinlein, Manfred
利用表达功能障碍和温度敏感的运动蛋白(MP)突变体的病毒衍生物对烟草花叶病毒(TMV)侵染的功能研究表明，TMV RNA的细胞间转运与MP与微管的结合在功能上有关。然而，微管在早期感染过程中的运动过程中的作用尚不清楚，因为MP在感染较晚的时候积累在微管上，并且用微管干扰剂处理植物时，未能强烈干扰TMV RNA在细胞之间的运动。为了进一步测试微管在烟草花叶病毒细胞间运动中的作用，我们研究了对运动温度敏感的TMV株系Ni2519。我们证明，运动中的温度敏感缺陷与微管上MP定位的温度敏感变化有关。此外，我们表明，在从不允许的条件下恢复的早期阶段，MP定位于微管相关颗粒。在传播TMV感染部位的前锋细胞中也发现了类似的颗粒。最初是移动的，当MP开始沿着与粒子相关的微管的长度积累时，粒子变得不能移动。我们的观察证实了微管在TMV感染传播中的作用，并将这一作用与微管相关的含MP颗粒在参与TMV基因组细胞间移动的细胞中的运输联系起来。
Functional studies of Tobacco mosaic virus (TMV) infection using virus derivatives expressing functional, dysfunctional, and temperature-sensitive movement protein (MP) mutants indicated that the cell-to-cell transport of TMV RNA is functionally correlated with the association of MP with microtubules. However, the role of microtubules in the movement process during early infection remains unclear, since MP accumulates on microtubules rather late in infection and treatment of plants with microtubule-disrupting agents fails to strongly interfere with cell-to-cell movement of TMV RNA. To further test the role of microtubules in TMV cell-to-cell movement, we investigated TMV strain Ni2519, which is temperature-sensitive for movement. We demonstrate that the temperature-sensitive defect in movement is correlated with temperature-sensitive changes in the localization of MP to microtubules. Furthermore, we show that during early phases of recovery from non-permissive conditions, the MP localizes to microtubule-associated particles. Similar particles are found in cells at the leading front of spreading TMV infection sites. Initially mobile, the particles become immobile when MP starts to accumulate along the length of the particle-associated microtubules. Our observations confirm a role for microtubules in the spread of TMV infection and associate this role with microtubule-associated trafficking of MP-containing particles in cells engaged in the cell-to-cell movement of the TMV genome.