Prokaryotic and eukaryotic RNA polymerases have homologous core subunits.
Prokaryotic and eukaryotic RNA polymerases have homologous core subunits.
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原核和真核RNA聚合酶具有同源的核心亚基。
DOI：
10.1073/pnas.84.5.1192
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发表时间：
1987
影响因子：
11.1
通讯作者：
Young,RA
中科院分区：
文献类型：
--
作者：
Sweetser,D;Nonet,M;Young,RA
真核RNA聚合酶是复杂的聚集体，其组成亚基在功能上定义不清。对编码酿酒酵母RNA聚合酶II 14万道尔顿亚基的基因进行了分离和详细研究，以获得该蛋白功能的线索。这个基因，RPB2，存在于单倍体基因组的一个拷贝中。基因的破坏对酵母细胞是致命的。RPB2编码一个138,750道尔顿的蛋白，其包含与嘌呤核苷酸和锌离子结合有关的序列，并与大肠杆菌RNA聚合酶的β亚基具有惊人的序列同源性。这些观察结果表明，酵母和大肠杆菌亚基在RNA合成中具有相似的作用，因为β亚基含有核苷酸底物的结合位点和RNA合成的部分催化位点。本文报道的亚基同源性，以及之前观察到的与最大RNA聚合酶亚基的同源性，表明原核RNA聚合酶“核心”酶的成分在真核RNA聚合酶中有对应的成分。
Eukaryotic RNA polymerases are complex aggregates whose component subunits are functionally ill-defined. The gene that encodes the 140,000-dalton subunit of Saccharomyces cerevisiae RNA polymerase II was isolated and studied in detail to obtain clues to the protein's function. This gene, RPB2, exists in a single copy in the haploid genome. Disruption of the gene is lethal to the yeast cell. RPB2 encodes a protein of 138,750 daltons, which contains sequences implicated in binding purine nucleotides and zinc ions and exhibits striking sequence homology with the beta subunit of Escherichia coli RNA polymerase. These observations suggest that the yeast and the E. coli subunit have similar roles in RNA synthesis, as the beta subunit contains binding sites for nucleotide substrates and a portion of the catalytic site for RNA synthesis. The subunit homologies reported here, and those observed previously with the largest RNA polymerase subunit, indicate that components of the prokaryotic RNA polymerase "core" enzyme have counterparts in eukaryotic RNA polymerases.