产品简介：

T-REx四环素诱导系统

A Tetracycline-Regulated Expression System without Viral Transactivators

The T-REx System yields higher levels of induced expression than any other regulated mammalian expression system. It utilizes the complete CMV promoter and adds control elements from the bacterial tetracycline resistance operon to effectively repress and derepress transcription from one of the strongest mammalian promoter sequences known (1,2).

Specific Activation

The T-REx System uses a repressor mechanism that blocks transcription from the powerful CMV promoter in the absence of tetracycline. Because the T-REx System elements do not use viral transactivators, you can achieve high-level expression from the complete CMV promoter without secondary, non-specific activation of host genes.

The T-REx Mechanism

The T-REx transcriptional control elements are illustrated in Figure 1. Two tetracycline operator sequences (TetO2) have been inserted between the TATA box of the CMV promoter and the transcriptional start site. The TetO2 sequence itself has no effect on expression. When the tetracycline repressor protein (TR) is present, it effectively binds the TetO2 sites and blocks transcription initiation. Tetracycline added to the culture medium binds to, and changes the conformation of, the TR protein. This change causes the TR protein to release the TetO2 sites, derepressing transcription from the CMV promoter. The result is high-level expression of the gene of interest (Figure 2). Expression levels can be modulated based on the tetracycline concentration and can be induced to levels that are achieved with constitutive CMV expression vectors.

T-REx is a powerful inducible mammalian expression system that allows you to regulate expression from the complete human cytomegalovirus (CMV) enhancer-promoter. T-RExinducible expression vectors offer the following features:

Complete CMV enhancer-promoter sequence containing two copies of the tetracycline operator TetO2 sequence for high-level regulated expression

Zeocin or hygromycin resistance gene for effective selection of stable mammalian cell lines

Large multiple cloning site to simplify cloning

In addition, pcDNA4/TO/myc-His offers a c-myc epitope for rapid detection of the recombinant protein with an Anti-myc Antibody and a polyhistidine (6xHis) sequence for simple purification of the recombinant protein with nickel-chelating resin and detection with Anti- His(C-term) Antibody.

The regulatory vector, pcDNA6/TR, is provided for high-level expression of the tetracycline repressor (TR) protein. This vector expresses the Blasticidin resistance gene for rapid selection of mammalian cell lines that stably express the TR protein.

产品参数：

质粒类型：四环素调控系统

出品公司：Invitrogen

启动子：CMV

克隆方法：多克隆位点，限制性内切酶

载体大小：5151bp 

5' 测序引物及序列：CMV-F; BGHrev

载体标签：c-myc, 6xHis

载体抗性：Ampicillin (氨苄青霉素)

筛选标记：Zeocin

备注：Mammalian cell vector for tetracycline-inducible expression of C-terminally Myc- and 6xHis-tagged proteins.