Adaptation of STARR-seq method to be used with 3rd generation integrase-deficient promoterless lentiviral vectors

Ability to functionally screen gene regulatory sequences, such as promoters and enhancers, in high throughput manner is an important prerequisite for many basic and translational research programs. One of the methods that allow such screening is STARR-seq, or self-transcribing active regulatory region sequencing. It allows to quickly screen millions of candidate sequences in the cell type of interest. However, it does rely on transfection as a delivery method which can be a limiting-step for some hard-to-transfect cells such as senescent cells. Here we show that integration-deficient and integration-competent promoterless lentiviral particles can be used to deliver STARR-seq constructs into cells. These constructs reported CMV enhancer activity both at protein and mRNA level. While further validations are necessary, ability to deliver STARR-seq libraries using lentiviral particles will significantly improve the versatility and usability of such a method.