"More than a billion people suffer from anemia. The only drug used to symptomatically increase red blood cell production in anemic patients is recombinant erythropoietin (Epo). While Epo injections effectively promote red blood cell production in patients suffering low endogenous Epo production, aplastic anemia and anemia associated with cancer, inflammation and infection do not respond well to recombinant Epo treatment.Aim A: Since there is a great need for new drugs that can treat Epo-resistant anemias the first aim of ERYTHROTHERAPY is to identify novel drug target for production of Epo-responsive cells. Using next-generation mRNA sequencing we identified 250 candidate genes that have the potential to be targeted by drugs and are highly expressed in red blood cell progenitor cells. RNA interference based screening strategies will be used to systematically characterize which if these genes can be targeted to promote red blood cell progenitor proliferation. If successful this study will lead to development of a novel class of erythropoiesis stimulating agents able to manage conditions that today lack pharmacological treatment.Aim B: The second goal of this project is to identify mechanism-based treatment strategies for Diamond-Blackfan anemia (DBA; OMIM #105650). All known DBA disease genes encode for ribosomal protein (RP) genes. Despite the recent advances in DBA genetics the pathophysiology remains elusive, which until now has prevented development of disease-specific therapies.In order to develop effective and specific DBA drugs the ERYTHROTHRAPY proposal uses an animal model for DBA to identify the molecular mechanisms linking RP-deficiency to anemia and bone marrow failure. Since limitations of previous mouse models for DBA make them unsuitable for this research strategy we generated a novel RP-deficient DBA mouse by taking advantage of Doxycycline-regulatable RNA interference. The drug-inducible strategy allows reversible and dose-dependent downregula"