Regulation of a new bacteriophage T4 gene, 69, that spans an origin of DNA replication.
Regulation of a new bacteriophage T4 gene, 69, that spans an origin of DNA replication.
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跨越 DNA 复制起点的新噬菌体 T4 基因 69 的调控。
DOI：
10.1002/j.1460-2075.1984.tb02221.x
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Mosig,G
中科院分区：
文献类型：
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作者：
Macdonald,PM;Mosig,G
我们已经确定了跨越DNA复制起点的3 kb片段（在标准噬菌体T4图谱上的15至18 kb之间）中的DNA序列和转录模式。一个新基因69跨越了这个起源。基因69编码两个重叠的蛋白质，它们共享一个共同的C末端片段。在一个适当的琥珀突变体的DNA复制缺陷表明，至少较大的两种蛋白质是需要有效的T4 DNA复制。由基因69编码的两种蛋白质由处于不同调控下的不同转录物表达。较小的蛋白质gp69* 可以从大肠杆菌样启动子立即表达，而较大的蛋白质gp69的表达必须延迟，因为其中间启动子需要T4编码的蛋白质，最有可能是gp mot，用于激活。我们讨论了两个重叠的蛋白质在复制体组装的可能意义。基因69由非必需的早期基因dam（DNA腺嘌呤甲基化酶）和晚期基因dam（小外壳蛋白）包围。通过该区域的转录物以复杂的模式相互交叉，这揭示了被认为在复制前和复制后T4基因调控中重要的所有元件。
We have determined the DNA sequence and transcription patterns in a 3‐kb segment (between 15 and 18 kb on the standard phage T4 map) spanning an origin of DNA replication. A new gene, 69, spans this origin. Gene 69 codes for two overlapping proteins that share a common C‐terminal segment. Defective DNA replication in an appropriate amber mutant shows that at least the larger of the two proteins is required for efficient T4 DNA replication. The two proteins coded by gene 69 are expressed from different transcripts that are under different regulation. The smaller protein, gp69*, can be expressed immediately from an Escherichia coli‐like promoter, whereas expression of the larger protein, gp69, must be delayed since its middle promoter requires T4 coded proteins, most likely gp mot, for activation. We discuss the possible significance of two overlapping proteins in the assembly of replisomes. Gene 69 is bracketed by the non‐essential early gene dam (DNA adenine methylase) and the late gene soc (small outer capsid protein). Transcripts through this region are interdigitated in a complex pattern, which reveals all elements that are thought to be important in regulation of pre‐replicative and post‐replicative T4 genes.