Pol-II Promoter

CHOOSE THE RIGHT POL-II PROMOTER

When setting up an experiment using lentiviral vectors, a necessary step is to test and compare different promoters.The choice of the promoter is a crucial parameter to design experimental strategies. Two parameters are to be considered:

  • Need for specific or ubiquitous transgene expression

  • Favor the number transduced of cells or the level of transgene expression per cell

 One of the most determinant element to achieve ideal transgene expression is the promoter. Inconveniently, its activity is subject to many parameters that will make its efficiency variable from one experiment to the next.

GEG-tech offers a large panel of specific and ubiquitous promoters to allow you to find the most relevant promoter(s) for your experimental studies. The choice of the promoter will be done according to the nature of the target cells and the desired level of expression. Once you have defined your criteria, GEG-tech suggests you test several promoters with a reporter construction. This first assay will help you to determine which promoter is the most suited for your project.

As an example, you may have a look at a study we performed to compare vectors expressing the GFP under the control of different ubiquitous promoters in basic cell lines. This study illustrates how the nature of the promoter and of the target cell interact to influence transgene expression and result in a wide range of transgene expressions.

Example 1: Ubiquitous expression

The transgene expression level per cell is influenced by the promoter and the nature of the target cells. The results below illustrate the relation between these parameters and show that each cell type is specific. We’ve tested Lenti-ONE™ expressing GFP under the control of 3 different ubiquitous promoters in 7 different cell lines.

INFLUENCE OF THE PROMOTER ON THE TRANSGENE EXPRESSION EFFICIENCY WITH Lenti-ONE™

Influence of promoter on transgene expression

Influence of the target cell type on the number of transduced cells with three Lenti-ONE eGFP. Expression is driven by three ubiquitous promoters (CMV, PGK or Ubiquitin). Note that:

  • for a given promoter, the number of transduced cells depends on the target cell type
  • the most efficient promoter depends on the target cell type
Influence of promoter on transgene expression

Influence of the target cell type on the transgene expression level per cell with three Lenti-ONE eGFP. Expression is driven by three ubiquitous promoters (CMV, PGK or Ubiquitin). Note that:

  • for a given promoter, the transgene expression level depends on the target cell type
  • the most efficient promoter depends on the target cell type

Also note that for a given cell line, the highest number of transduced cells and the highest level of expression per transduced cells are not necessarily obtained with the same promoter.

Example 2: Cell specific expression

In the same approach, if you want to test different specific promoters for your study, you’ll have the chance to customize your own Promoter Set and to formulate your request to our On-Demand Services.