We developed a new high-throughput assay, called Sensor-Seq, which allows us to simultaneously quantify the activity of hundreds of miRNAs. Traditional small RNA profiling only gives information about the concentration of each microRNA in the cell. However, miRNA activity can be affected by multiple factors, such as target abundance or intracellular compartimentalization. Our Sensor-seq approach adds an extra layer of valuable information to the traditional profiling, since it provides data of the actual functional activity of each microRNA in a cell. We are interested in using this approach to generate a map of miRNA activity across the different cell types in the immune system, and use it for better cell-specific targeting of gene transfer vectors. We also want to further explore and identify different mechanisms that might be involved in the post-transcriptional regulation of miRNA activities.
To help us study miRNA functions, we built a novel library of miRNA “decoys” or “sponges”. This library can be used for miRNA loss-of-function screens to identify new roles of miRNAs and even to explore new therapeutic possibilities.