Large-scale cell-based microarrays and their use with HEK293T cells and downstream apoptotic assays

Cell-based microarrays are a powerful technology platform for performing high-throughput screens of gene function. The approach entails printing expression vectors containing either genes or shRNAs onto a glass microscope slide or 384-well microtitre plate to form an array. These vectors are then packaged in lipid-based transfection reagent, cells grown over the top of the array are transfected and the arrays can then be examined for alterations in cellular function as manifested in localised changes to the cells biochemistry or morphology. We have used this technology for two purposes: to study the sub-cellular localisation of proteins and to perform a large-scale screen for genes that when over-expressed lead to apoptotic cell death. Here we have provided detailed protocols for the large-scale screen and discuss some of the issues associated with this technology.