The publication of the human genome sequence has increased the need for high-throughput approaches to undertake functional annotation analysis. In an Advanced Online Publication in
The adenovirus system offers broad tropism, allowing the efficient delivery of cDNAs to different cell-types for systematic screening based on cellular phenotypes. Michiels et al. constructed arrays of replication-defective adenoviruses containing cDNA library clones — that they named 'PhenoSelect' libraries — and demonstrated the power of this approach by screening for genes that affect osteoblast differentiation. They transduced primary human mesenchymal cells, screened for the induction of alkaline phosphatase activity and isolated known (BMPs and FosB) and novel inducers of osteoblast differentiation. In addition they were able to isolate genes involved in metastasis and angiogenesis phenotypes.