Nakahama K, Yasukawa H, Kimura T, Mizuno K, Hiraiwa T, Ozaki E, Masamune Y
Department of Microbiology, Faculty of Pharmaceutical Sciences, Kanazawa University, Japan.
DNA Res. 1997 Jun 30;4(3):199-204. doi: 10.1093/dnares/4.3.199.
Replication of rolling circle plasmid pKYM was regulated by RepK, a plasmid-encoded initiator protein, with HU protein and antisense RNA (copRNA) that block the expression of RepK. HU protein bound to the repK promoter in the presence of RepK protein and inhibited the transcription of repK mRNA. The copRNA would hybridize to repK mRNA and induce a stem-loop structure in which the repK Shine-Dalgarno sequence is sequestered by base pairing. Sequence substitution experiments demonstrated that this stem-loop not only inhibits translation but induces premature termination.
滚环质粒pKYM的复制由质粒编码的起始蛋白RepK调控，同时受到HU蛋白和反义RNA（copRNA）的影响，后者会阻断RepK的表达。在RepK蛋白存在的情况下，HU蛋白与repK启动子结合，抑制repK mRNA的转录。copRNA会与repK mRNA杂交并诱导形成一种茎环结构，其中repK的Shine-Dalgarno序列通过碱基配对被隔离。序列替换实验表明，这种茎环结构不仅抑制翻译，还会诱导提前终止。
