Rea1, a dynein-related nuclear AAA-ATPase, is involved in late rRNA processing and nuclear export of 60 S subunits
Rea1, a dynein-related nuclear AAA-ATPase, is involved in late rRNA processing and nuclear export of 60 S subunits
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DOI：
10.1074/jbc.m406876200
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发表时间：
2004-12-31
影响因子：
4.8
通讯作者：
Hurt, E
中科院分区：
文献类型：
--
作者：
Galani, K;Nissan, TA;Hurt, E
Rea 1是酵母基因组中最大的预测蛋白，是ATP酶AAA（+）家族的成员，与前60 S核糖体相关。在这里，我们报告说，Rea 1是所需的成熟和核出口的前60 S亚基。Rea 1表现出主要的核质定位，并存在于一个晚前60 S颗粒连同Rix 1复合物的成员。为了研究Rea 1在核糖体生物发生中的作用，我们产生了可抑制的GAL：：REA 1菌株和温度敏感的rea 1等位基因。在体内耗尽的Rea 1的结果在成熟的60 S亚基的显着减少伴随着缺陷的前rRNA加工和后期前60 S核糖体的稳定性ITS 2切割后和成熟的5.8 S rRNA的产生之前。耗尽Rix 1复合物的组分（Rix 1、Ipi 1和Ipi 3）的菌株显示出类似的缺陷。使用体内60 S亚基输出测定，在限制性条件下，在real突变体中观察到大亚基报告基因Rp 125-GFP（绿色荧光蛋白）在细胞核和细胞核周边的强烈积累。
Rea1, the largest predicted protein in the yeast genome, is a member of the AAA(+) family of ATPases and is associated with pre-60 S ribosomes. Here we report that Rea1 is required for maturation and nuclear export of the pre-60 S subunit. Rea1 exhibits a predominantly nucleoplasmic localization and is present in a late pre-60 S particle together with members of the Rix1 complex. To study the role of Rea1 in ribosome biogenesis, we generated a repressible GAL::REA1 strain and temperature-sensitive rea1 alleles. In vivo depletion of Rea1 results in the significant reduction of mature 60 S subunits concomitant with defects in pre-rRNA processing and late pre-60 S ribosome stability following ITS2 cleavage and prior to the generation of mature 5.8 S rRNA. Strains depleted of the components of the Rix1 complex (Rix1, Ipi1, and Ipi3) showed similar defects. Using an in vivo 60 S subunit export assay, a strong accumulation of the large subunit reporter Rpl25-GFP (green fluorescent protein) in the nucleus and at the nuclear periphery was seen in rea1 mutants at restrictive conditions.