AtPARN is an essential poly(A) ribonuclease in Arabidopsis
AtPARN is an essential poly(A) ribonuclease in Arabidopsis
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DOI：
10.1016/j.gene.2003.11.028
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发表时间：
2004-03-17
期刊：
影响因子：
3.5
通讯作者：
Green, PJ
中科院分区：
文献类型：
--
作者：
Chiba, Y;Johnson, MA;Green, PJ
脱腺苷酸化是从酵母到高等真核生物的许多生物体中许多mRNA降解的第一步和限速步骤。它还可以在早期发育中发挥调节作用。在这项研究中，我们研究了拟南芥同源物的聚（A）核糖核酸酶（PARN），deadenylase首次发现在哺乳动物和酵母缺席。与对催化活性重要的结构域和残基的保守性一致，在大肠杆菌中表达的拟南芥PARN（AtPARN）在体外具有poly（A）降解活性。植物细胞中的蛋白定位实验表明AtPARN存在于细胞核和细胞质中。为了解决酶在体内的重要性，我们确定了三个独立的T-DNA插入突变体的AtRARN中断的基因在不同的位置之间的ATG和终止密码子。所有三个等位基因导致种子萌发前的致死性，表明AtRARN是一个必不可少的基因，首先需要在早期发展。虽然同源基因尚未在任何其他生物体中失活，但我们的观察表明PARN至关重要，并表明它可能在许多其他多细胞真核生物中是必不可少的。(C)2004 Elsevier B. V.保留所有权利。
Deadenylation is the first and rate-limiting step in the degradation of many mRNAs in a wide-range of organisms from yeast to higher eukaryotes. It can also play a regulatory role in early development. In this study, we examined the Arabidopsis homolog of poly(A) ribonuclease (PARN), a deadenylase first identified in mammals and absent from yeast. Consistent with the conservation of domains and residues important for catalytic activity, Arabidopsis PARN (AtPARN) expressed in Escherichia coli has poly(A) degradation activity in vitro. Protein localization experiments in plant cells indicate that AtPARN resides in both the nucleus and cytoplasm. To address the importance of the enzyme in vivo, we identified three independent T-DNA insertion mutants of AtRARN which interrupt the gene at different positions between the ATG and the stop codon. All three alleles cause lethality prior to seed germination, indicating that AtRARN is an essential gene first required during early development. Although homologous genes have yet to be inactivated in any other organism, our observations argue for the critical importance of PARN and suggest that it may be essential in many other multicellular eukaryotes. (C) 2004 Elsevier B.V. All rights reserved.