BACTERIOPHAGE-T4 ANTICODON NUCLEASE, POLYNUCLEOTIDE KINASE AND RNA LIGASE REPROCESS THE HOST LYSINE TRANSFER-RNA
BACTERIOPHAGE-T4 ANTICODON NUCLEASE, POLYNUCLEOTIDE KINASE AND RNA LIGASE REPROCESS THE HOST LYSINE TRANSFER-RNA
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DOI：
10.1002/j.1460-2075.1987.tb02532.x
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发表时间：
1987-08-01
期刊：
影响因子：
11.4
通讯作者：
KAUFMANN, G
中科院分区：
文献类型：
--
作者：
AMITSUR, M;LEVITZ, R;KAUFMANN, G
宿主trna在抗密码子附近切割，特异地发生在t4感染的大肠杆菌prr菌株中，这些菌株限制多核苷酸激酶（pnk）或RNA脂肪酶（rli）噬菌体突变体。切割产物在wt中是短暂的，但在粉色和rli感染中积累，这表明受影响的酶参与了受损trna的修复。通过比较突变体感染中间体与完整的tRNA对应物在wt感染前或晚期的作用，阐明了它们在该途径中的作用。因此，t4诱导的抗密码子核酸酶将赖氨酸tRNA 5”切割到摆动位置，产生2”：3”-P >和5”-OH末端。多核苷酸激酶将它们转化为由RNA连接酶依次连接的3' -OH和5' P对。据推测，在缺乏多核苷酸激酶和RNA连接酶介导的修复的情况下，赖氨酸tRNA耗损是prr限制的基础。然而，核酸酶、激酶和连接酶可能通过调整宿主trna的水平或解码特异性来适应T4密码子的使用，从而直接使T4受益。
Host tRNAs cleaved near the anticodon occur specifically in T4-infected Escherichia coli prr strains which restrict polynucleotide kinase (pnk) or RNA lipase (rli) phage mutants. The cleavage products are transient with wt but accumulate in pnk- and rli- infections, implicating the affected enzymes in repair of the damaged tRNAs. Their roles in the pathway were elucidated by comparing the mutant infection intermediates with intact tRNA counterparts before or late in wt infection. Thus, the T4-induced anticodon nucleases cleaves lysine tRNA 5'' to the wobble position, yielding 2'':3''-P > and 5''-OH termini. Polynucleotide kinase converts them into a 3''-OH and 5'' P pair joined in turn by RNA ligase. Presumably, lysine tRNA depletion, in the absence of polynucleotide kinase and RNA ligase mediated repair, underlies prr restriction. However, the nuclease, kinase and ligase may benefit T4 directly, by adapting levels or decoding specificities of host tRNAs to T4 codon usage.