来自噬菌体fd单链到双链DNA复制起点的一个DNA片段。

Schaller H, Uhlmann A, Geider K

Proc Natl Acad Sci U S A. 1976 Jan;73(1):49-53. doi: 10.1073/pnas.73.1.49.

A specific complex is formed between fd DNA, Escherichia coli DNA unwinding protein, and RNA polymerase (EC 2.7.7.6; nucleosidetriphosphate:RNA nucleotidyltransferase) during the first steps in the conversion of the single-stranded viral DNA to the double-stranded replicative form. In this complex a unique DNA fragment of about 120 nucleotides is protected against nuclease digestion. Both the requirements for its isolation and its position on the map of the phage genome indicate that the fragment contains the origin of single-strand to double-strand DNA replication. The isolated DNA fragment possesses double-strand-like characteristics, which protect it from being covered by the DNA unwinding protein and thus indirectly positions the RNA polymerase to the origin of replication.

在单链病毒DNA转化为双链复制形式的起始步骤中，fd DNA、大肠杆菌DNA解旋蛋白和RNA聚合酶（EC 2.7.7.6；核苷三磷酸：RNA核苷酸转移酶）之间形成了一种特定的复合物。在这种复合物中，一个约120个核苷酸的独特DNA片段受到核酸酶消化的保护。其分离的条件及其在噬菌体基因组图谱上的位置都表明，该片段包含单链到双链DNA复制的起始点。分离出的DNA片段具有双链样特征，这使其免受DNA解旋蛋白的覆盖，从而间接将RNA聚合酶定位到复制起始点。