Investigations of plant cell division would greatly benefit from a fast, inducible system. Therefore, we aimed to establish a mitotic model by transiently expressing D-type cyclins in tobacco leaf cells. Two different D-type cyclins, CYCD3;1 and CYCD4;2 from Arabidopsis thaliana, were expressed by agrobacterial infiltration in the cells of expanded leaves in tobacco (Nicotiana benthamiana). Leaf pavement cells were examined after cyclin expression while target and reference (histone or tubulin) proteins were marked by fluorescent protein-tagging. Ectopic expression of the D-type cyclin induced pavement cells to re-enter cell division by establishing mitotic microtubule arrays. The induced leaf cells expressed M phase-specific genes of Arabidopsis encoding the mitotic kinase AtAurora 1, the microtubule-associated proteins AtEDE1 and AtMAP65-4, and the vesicle fusion protein AtKNOLLE by recognizing their genomic elements. Their distinct localizations at spindle poles (AtAurora1), spindle microtubules (AtEDE1), phragmoplast microtubules (AtMAP65-4) and the cell plate (AtKNOLLE) were indistinguishable from those in their native Arabidopsis cells. The dividing cells also revealed two rice (Oryza sativa) microtubule-associated proteins in the phragmoplast and uncovered a novel spindle-associated microtubule motor protein. Hence, this cell division-enabled leaf system predicts hypothesized cell cycle-dependent functions of heterologous genes by reporting the dynamics of encoded proteins.

中文翻译：

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通过在烟草（Nicotiana Benthamiana）分化叶细胞中瞬时表达 D 型细胞周期蛋白来建立有丝分裂模型系统。


植物细胞分裂的研究将大大受益于快速的诱导系统。因此，我们旨在通过在烟草叶细胞中瞬时表达D型细胞周期蛋白来建立有丝分裂模型。来自拟南芥的两种不同的 D 型细胞周期蛋白 CYCD3;1 和 CYCD4;2 通过农杆菌浸润在烟草 (Nicotiana Benthamiana) 的展开叶细胞中表达。在细胞周期蛋白表达后检查叶铺细胞，同时通过荧光蛋白标签标记靶蛋白和参考蛋白（组蛋白或微管蛋白）。 D 型细胞周期蛋白的异位表达通过建立有丝分裂微管阵列诱导路面细胞重新进入细胞分裂。诱导的叶细胞通过识别其基因组元件，表达拟南芥的 M 期特异性基因，编码有丝分裂激酶 AtAurora 1、微管相关蛋白 AtEDE1 和 AtMAP65-4 以及囊泡融合蛋白 AtKNOLLE。它们在纺锤体极 (AtAurora1)、纺锤体微管 (AtEDE1)、成膜体微管 (AtMAP65-4) 和细胞板 (AtKNOLLE) 上的独特定位与其天然拟南芥细胞中的定位没有区别。分裂细胞还在成膜体中发现了两种水稻（Oryza sativa）微管相关蛋白，并发现了一种新型纺锤体相关微管运动蛋白。因此，这种支持细胞分裂的叶系统通过报告编码蛋白质的动态来预测假设的异源基因的细胞周期依赖性功能。