Mouse primase initiation sites in the origin region of simian virus 40.
Mouse primase initiation sites in the origin region of simian virus 40.
复制标题
猴病毒 40 起源区域的小鼠引物酶起始位点。
DOI：
10.1073/pnas.81.8.2342
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发表时间：
1984
影响因子：
11.1
通讯作者：
Ahlem,CN
中科院分区：
文献类型：
--
作者：
Tseng,BY;Ahlem,CN
研究了猴病毒40（SV 40）复制起点区中纯化的小鼠DNA引发酶的DNA合成起始位点。使用作为模板的分离的链的克隆片段的SV 40约等于300碱基对（bp）长，包括起源，我们观察到的特定位点的两条链上的起始。在作为早期mRNA合成模板的早期链上，主要起始点位于核苷酸5215周围的10个核苷酸内的4个位置，以及核苷酸5147周围的一个额外位点，该位点以主要位点的六分之一频率使用。早期链上的主要起始位点在65-bp最小复制起点内，并且位于肿瘤抗原结合位点I和II之间。在作为晚期mRNA合成模板的晚期链上，观察到六个主要起始位点，每个在模板中的3' C-C-C-G-C-C 5'序列内，其在位于最小起点附近的三个21-bp重复序列中的每一个内重复两次，在其晚期侧。在65-bp的最小起点，消除其作为一个起点的功能，减少了90%的早期链上的核苷酸5215周围的主要起始，但不影响在早期链或启动后期链的次要起始位点的6-bp缺失。小鼠DNA引物酶能够识别SV 40 DNA上的特定区域。早期链上的那些在最小复制起点内，晚期链上的那些在最大复制所需的21-bp重复区域内。
The sites of initiation of DNA synthesis by purified mouse DNA primase in the origin-of-replication region of simian virus 40 (SV40) were examined. Using as template the separated strands of a cloned fragment of SV40 approximately equal to 300 base pairs (bp) long that includes the origin, we observed specific sites of initiation on the two strands. On the early strand that is the template for early mRNA synthesis, the primary starts are at four positions within 10 nucleotides of each other around nucleotide 5215 and an additional site around nucleotide 5147 that is used at one-sixth the frequency of the major sites. The major start sites on the early strand are within the 65-bp minimal origin of replication and lie between tumor antigen binding sites I and II. On the late strand that is the template for late mRNA synthesis, six major initiation sites were observed, each within the 3' C-C-C-G-C-C 5' sequence in the template that is repeated twice within each of the three 21-bp repeats that lie adjacent to the minimal origin, on its late side. A 6-bp deletion in the 65-bp minimal origin that eliminates its function as an origin reduced the major initiations around nucleotide 5215 on the early strand by 90% but did not affect initiations at the minor start site on the early strand or initiations on the late strand. Mouse DNA primase is able to recognize specific regions on the SV40 DNA. Those on the early strand are within the minimal origin of replication and those on the late strand are within the 21-bp repeat region necessary for maximum replication.