Structure of yeast poly(A) polymerase alone and in complex with 3′-dATP
Structure of yeast poly(A) polymerase alone and in complex with 3′-dATP
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DOI：
10.1126/science.289.5483.1346
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发表时间：
2000-08-25
期刊：
影响因子：
56.9
通讯作者：
Bohm, A
中科院分区：
文献类型：
--
作者：
Bard, J;Zhelkovsky, AM;Bohm, A
多聚腺苷[聚(A)]聚合酶(PAP)催化几乎所有真核生物信使RNA(MRNAs)上加成一条多腺苷尾巴。酿酒酵母PAP(PAP1)的晶体结构单独或与3‘-脱氧三磷酸脱氧腺苷(3’-dATP)络合物均为2.6埃。与其他核酸聚合酶一样，PAP1由三个围绕活性部位的结构域组成。然而，这些结构域的排列与聚合酶中看到的非常不同，聚合酶使用模板来选择和定位它们进入的核苷酸。前两个结构域在功能上类似于聚合酶手掌和手指结构域。第三个结构域连接到Fingers结构域，并已知与单链RNA引物相互作用。在核苷酸复合体中，两个3‘-dATP分子与PAP1结合，一个分子占据进入碱基的位置，然后添加到mRNA链上。另一个被认为占据了mRNA3‘端的位置。
Polyadenylate [poly(A)] polymerase (PAP) catalyzes the addition of a polyadenosine tail to almost all eukaryotic messenger RNAs (mRNAs). The crystal structure of the PAP from Saccharomyces cerevisiae (Pap1) has been solved to 2.6 angstroms, both alone and in complex with 3'-deoxyadenosine triphosphate (3'-dATP). Like other nucleic acid polymerases, Pap1 is composed of three domains that encircle the active site. The arrangement of these domains, however, is quite different from that seen in polymerases that use a template to select and position their incoming nucleotides. The first two domains are functionally analogous to polymerase palm and fingers domains. The third domain is attached to the fingers domain and is' known to interact with the single-stranded RNA primer. In the nucleotide complex, two molecules of 3'-dATP are bound to Pap1, One occupies the position of the incoming base, prior to its addition to the mRNA chain. The other is believed to occupy the position of the 3' end of the mRNA primer.