Fig. 1: shRNA-based selection of positive regulators of cell migration.

A Overview of the selection procedure. The production and infection of a ubiquitination-related lentiviral shRNA library are described in Methods. Two weeks after lentiviral infection and selection, MDAMB231 cells were seeded onto transwell inserts and allowed to migrate across the porous membrane for 24 h in order to select cells with a decreased migration phenotype. Migrating cells were removed and non-migrating cells were collected from the inserts upper compartment and amplified. Cells were then reseeded onto transwell culture inserts for a subsequent cycle of selection; this procedure was repeated until cells lost 80% of their initial migratory potential. After every cycle of selection, the relative abundance of the different shRNAs was evaluated using Next-Generation Sequencing. B Transwell assay was used every other enrichment cycle to determine the percentage of migratory cells and monitor the selection process. C shRNAs’ abundance was estimated after each selection cycle.