A UNIQUE STRUCTURE AT THE CARBOXYL TERMINUS OF THE LARGEST SUBUNIT OF EUKARYOTIC RNA POLYMERASE-II
A UNIQUE STRUCTURE AT THE CARBOXYL TERMINUS OF THE LARGEST SUBUNIT OF EUKARYOTIC RNA POLYMERASE-II
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DOI：
10.1073/pnas.82.23.7934
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发表时间：
1985-01-01
影响因子：
11.1
通讯作者：
DAHMUS, ME
中科院分区：
文献类型：
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作者：
CORDEN, JL;CADENA, DL;DAHMUS, ME
纯化的真核核RNA聚合酶II由三个亚种组成，其最大亚基的表观分子质量不同，分别为IIo， IIa和IIb，分别命名为IIo， IIa和IIb。亚基IIo， IIa和IIb是单个基因的产物。我们在此提出了小牛胸腺亚基IIa和IIb的氨基酸组成，以及从编码该RNA聚合酶亚基的部分小鼠基因的核苷酸序列推断出的IIa亚基（IIo）的c端氨基酸序列。计算出IIa亚基所特有的肽的氨基酸组成表明，IIa亚基含有一个富含丝氨酸、脯氨酸、苏氨酸和酪氨酸的结构域。小鼠RNA聚合酶II最大亚基基因3”末端的序列显示，c端结构域由52个重复的7个氨基酸块组成，一致序列为tyrr - ser - pro - thr - ser - pro - ser。这个序列也很不寻常，因为它含有很高比例的潜在磷酸化位点。
Purified eukaryotic nuclear RNA polymerase II consists of three subspecies that differ in the apparent molecular masses of their largest subunit, designated IIo, IIa, and IIb for polymerase species IIO, IIA, and IIB, respectively. Subunits IIo, IIa, and IIb are the products of a single gene. We present here the amino acid composition of calf thymus subnits IIa and IIb and the C-terminal amino acid sequence of subunit IIa (IIo) inferred from the nucleotide sequence of part of the mouse gene encoding this RNA polymerase subunit. The calculated amino acid composition of the peptide unique to subunit IIa indicates that subunit IIa contains a domain rich in serine, proline, threonine, and tyrosine. The sequence at the 3'' end of the mouse RNA polymerase II largest subunit gene reveals that the C-terminal domain consists of 52 repeats of a seven amino acid block with the consensus sequence Tyr-Ser-Pro-Thr-Ser-Pro-Ser. This sequence is also unusual in that it contains a high percentage of potential phosphorylation sites.