The putative RNA-processing protein, THO2, is a microtubule-associated protein in tobacco
The putative RNA-processing protein, THO2, is a microtubule-associated protein in tobacco
复制标题
假定的 RNA 加工蛋白 THO2 是烟草中的一种微管相关蛋白
DOI：
10.1093/pcp/pcp024
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发表时间：
2009
影响因子：
4.9
通讯作者：
and Sonobe. S.
中科院分区：
文献类型：
--
作者：
Hamada;T.;Igarashi;H.;Taguchi;R.;Fujiwara;M.;Fukao;Y.;Shimmen;T.;Yokota;E.;and Sonobe. S.
THO2是THO-TREX(转录和输出因子)复合体的一个组成部分，参与酵母和动物细胞中的mRNA新陈代谢和细胞核输出。本文报道了烟草THO2相关蛋白(NtTHO2)是一种微管相关蛋白，在体外直接与微管结合，在体内与皮质微管共定位。我们通过微管聚合-解聚循环从烟草BY-2小原生质体粗提物中提纯内源NtTHO2。纯化的NtTHO2在体外与微管沉淀。免疫荧光显示NtTHO2存在于胞核和胞浆中。间期胞质NtTHO2沿皮质微管定位。在有丝分裂阶段，NtTHO2定位于有丝分裂纺锤体，但不定位于前相带和膜质。在幼苗根的成熟细胞和通过去除2，4-D而停止增殖的BY-2细胞中，NtTHO2染色主要局限于核仁。这些结果表明，NtTHO2是一种多功能蛋白，参与了mRNA的代谢，并在皮质微管和有丝分裂纺锤体中发挥作用。
THO2 is a component of the THO–TREX (transcription and export factor) complex that participates in mRNA metabolism and export from the nucleus in yeast and animal cells. Here we report that tobacco putative THO2-related protein (NtTHO2) is a microtubule-associated protein, which directly binds to microtubules in vitro and co-localizes with cortical microtubules in vivo. We purified endogenous NtTHO2 by cycles of microtubule polymerization–depolymerization from crude extracts of tobacco BY-2 miniprotoplasts. Purified NtTHO2 sedimented with microtubules in vitro. Immunofluore-scence revealed that NtTHO2 was present in both the nucleus and cytoplasm. In interphase, cytoplasmic NtTHO2 was localized along cortical microtubules. In the mitotic phase, NtTHO2 was localized to the mitotic spindle but not to either the preprophase band or the phragmoplast. In mature cells of seedling roots, and in BY-2 cells in which proliferation was stopped by removing 2,4-D, NtTHO2 staining was confined mainly to the nucleolus. These results suggest that NtTHO2 is a multifunctional protein that participates in mRNA metabolism, and also functions within the cortical microtubules and mitotic spindle.