described. Reduced frequency of the side population was observed in SALL4knockdown cells on the lower pane. (B) qRT-PCR analysis showed that SALL4 expression was reduced by 40% in the SALL4 shRNA-treated SP KG1a cells when compared to that of scramble control shRNA treated ones. (TIF) Figure S5 Endogenous SALL4 specifically binds to the ABCA3 promoter revealed by ChIP assay. Using KG1a cells, ChIP assay was performed by using two antibodies against SALL4 (Sall4-(1): SantaCruz (EE30), (2):in-house antibody) or mouse IgG as a negative control. Enriched chromatin was analyzed by PCR and elctroporesed on agarose gel. (TIF) Figure S6 Activation of the promoter of ABCA3 by SALL4. (A) Diagram of ABCA3-Luc construct which contained the SALL4 binding site. (B) ABCA3-Luc construct was cotrans- fected to HeLa or 293 (data not shown) cells with Renilla luciferase plasmid and increasing ratios of either the SALL4A (gray bars) or SALL4B (black bars) overexpressing constructs. pcDNA (white bars) was used as a control. Data represent the mean of three different experiments. X axis: relative luciferase activity (fold) after overexpression of SALL4A or B in comparison to that of control vector. Y axis: ratio of SALL4A or B construct to control. (TIF) Figure S7 Down-regulation of SALL4 in CD34+ cells. CD34+ cells were transduced with retrovirus expressing shRNA against SALL4 and subjected to qRT-PCR analysis to measure the expression levels of SALL4 The expression level of SALL4 was reduced by 70% mRNA level was normalized with the internal control GAPDH (N = 3). (TIF) Figure S8 SALL4 is preferentially expressed in SP cells in breast cancer cell line MCF7. 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