RNA polymerase II subunit RPB4 is essential for high- and low-temperature yeast cell growth.
RNA polymerase II subunit RPB4 is essential for high- and low-temperature yeast cell growth.
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RNA 聚合酶 II 亚基 RPB4 对于高温和低温酵母细胞生长至关重要。
DOI：
10.1128/mcb.9.7.2854-2859.1989
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发表时间：
1989
影响因子：
5.3
通讯作者：
Young,RA
中科院分区：
文献类型：
--
作者：
Woychik,NA;Young,RA
RPB 4编码酿酒酵母中第四大RNA聚合酶II亚基，对RPB 4基因进行了克隆和序列测定，并对纯化的亚基进行了胰蛋白酶肽段氨基酸序列分析。RPB 4DNA序列预测蛋白质为221个氨基酸，分子量为25，414道尔顿。发现RPB 4蛋白的中心100个氨基酸类似于大肠杆菌RNA聚合酶中的主要σ亚基的片段。RPB 4的缺失产生的细胞对热和冷敏感，但可以在中等温度下生长，尽管生长缓慢。RNA聚合酶II缺乏RPB4亚基表现出显着降低活性的粗提物在体外。RPB 4亚基，虽然不是必不可少的mRNA合成或酶的装配，是必不可少的RNA聚合酶II活性的正常水平和不可或缺的细胞活力在很宽的温度范围内。
RPB4encodes the fourth-largest RNA polymerase II subunit inSaccharomyces cerevisiae, TheRPB4gene was cloned and sequenced, and its identity was confirmed by amino acid sequence analysis of tryptic peptides from the purified subunit. TheRPB4DNA sequence predicted a protein of 221 amino acids with a molecular mass of 25,414 daltons. The central 100 amino acids of the RPB4 protein were found to be similar to a segment of the major sigma subunit inEscherichia coliRNA polymerase. Deletion ofRPB4produced cells that were heat and cold sensitive but could grow, albeit slowly, at intermediate temperatures. RNA polymerase II lacking the RPB4 subunit exhibited markedly reduced activity in crude extracts in vitro. The RPB4 subunit, although not essential for mRNA synthesis or enzyme assembly, was essential for normal levels of RNA polymerase II activity and indispensable for cell viability over a wide temperature range.