RPS19 overexpression rescues the hematopoietic defect in vitro. (A) Design of lentiviral rescue vector overexpressing a codon-optimized human RPS19 and GFP, and the control vector expressing only GFP. (B) c-Kit–enriched hematopoietic progenitors from uninduced mice were transduced, and their proliferation was assayed in liquid cultures in presence of doxycycline. (C) BFU-E colony forming potential of transduced hematopoietic progenitors in presence of doxycycline. Data shown are from a single experiment but are representative of 2 repeat experiments. RSV indicates Rous sarcoma virus; ψ, packaging signal; SD, splice donor; RRE, rev responsive element; SA, splice acceptor; cPPt, polypurine tract; SFFV, spleen focus forming virus promoter; PRE, posttranscriptional regulatory element; IRES, internal ribosome entry site; and GFP, green fluorescent protein.