"Leukemic cells, similar to other types of cancer cells, are characterized by aberrant epigenetic changes, which often lead to abnormal expression of oncogenes and tumor suppressor genes. The goal of this project is to identify and characterize new regulators of normal and malignant hematopoiesis. We propose two complementary loss-of-function screens, using shRNA vectors against two groups of histone modifying enzymes, histone methyltransferases and histone demethylases.We plan to perform an in vitro shRNA screen, infecting mouse primary cells with lentiviruses based on single pLKO.1 vectors. We will assess the effect of down-regulation of a specific protein by flow cytometry analysis. In parallel, we will carry out an in vivo shRNA screen in a mouse model of human acute myeloid leukemia (AML). Mouse leukemic cells will be infected with a pooled retroviral shRNA library and transplanted into a small number of recipient mice. When the recipient mice develop AML, the leukemic cells will be harvested and high-throughput sequencing of shRNAs will be used to determine shRNAs depleted or enriched during initiation and progression of AML.Selected candidate genes will be validated and further characterized using in vitro and in vivo assays. Moreover, we will search for molecular mechanisms mediating the function of validated candidates in normal hematopoiesis and/or leukemia. I strongly believe that this project can lead to a discovery of novel oncogenes and/or tumor suppressors involved in AML, and potentially also to design of novel therapies for leukemia treatment."