Figure 5 - A decrease in Foxo1 protein in primary B lymphocytes decreases Rag1 transcription at all stages of B cell development.

(a) GFP expression in cultured hCD2⁺B220⁺CD43^- IgM^- bone marrow pre–B cells from Rag1-GFP–heterozygous mice, infected with retrovirus expressing shRNA specific for Foxo1, Foxo3a or GFP (solid lines) or empty vector (filled histograms; repeated in each plot for reference), collected 3–4 d later and labeled with antibodies to delineate B cell developmental subsets and 'mark' retrovirus-infected cells. Numbers at top left indicate GFP mean fluorescence intensity; the value for the population infected with empty vector retrovirus is 127. (b) GFP mean fluorescence intensity (MFI) for shRNA retrovirus infection experiments done as described in a, presented as a percent of the GFP mean fluorescence intensity for the population infected with empty vector retrovirus (set as 100%), analyzing pro–B cell, pre–B cell and immature B cell populations gated on live cells and B220. Data are representative of three experiments (a) or are the average of three independent experiments ( s.d.; b).