一种能对插入片段进行阳性筛选的质粒克隆载体。

A plasmid cloning vehicle allowing a positive selection for inserted fragments.

作者信息

Roberts T M, Swanberg S L, Poteete A, Riedel G, Backman K

出版信息

Gene. 1980 Dec;12(1-2):123-7. doi: 10.1016/0378-1119(80)90022-0.

Abstract

We describe a plasmid cloning vehicle, pTR262, which allows a strong positive selection (resistance to tetracycline) for transformants bearing plasmids which have DNA insertions. pTR262 is derived from plasmid pBR322 and contains the cI gene and adjacent regulator region oRpR or the bacteriophage lambda. The expression of the tetracycline resistance (tet-r) gene(s) in pTR262 requires transcription from pR and is repressed by the cI gene product, lambda repressor. Insertion of a DNA fragment into the HindIII or Bc/I sites in pTR262 inactivates the cI gene and allows expression of the tet-r gene(s) in the host bacterium. A 100-fold increase in the number of tetracycline-resistant transformants is obtained when HindIII- or Bc/I-generated fragments are added to a ligation mixture containing HindIII- or Bc/I-digested pTR 262 DNA.

摘要

我们描述了一种质粒克隆载体pTR262，它能对携带插入了DNA的质粒的转化体进行强阳性选择（对四环素耐药）。pTR262源自质粒pBR322，含有噬菌体λ的cI基因及相邻的调节区域oRpR。pTR262中四环素抗性（tet-r）基因的表达需要从pR进行转录，并受到cI基因产物λ阻遏物的抑制。将DNA片段插入pTR262的HindIII或Bc/I位点会使cI基因失活，并允许tet-r基因在宿主细菌中表达。当将HindIII或Bc/I产生的片段添加到含有经HindIII或Bc/I消化的pTR 262 DNA的连接混合物中时，四环素抗性转化体的数量会增加100倍。