Figure 8

Forced expression of PU.2 in K562 cells induces spontaneous erythroid differentiation. (A) Cell pellets of K562 lines infected with pMSCVpuro-Pu.1, pMSCVhyg-Pu.2, pMSCVpuro-Pu.1 plus pMSCVhyg-Pu.2, and empty vector (pMSCVpuro plus pMSCVhyg). Hemoglobinization (signified by red hue) is apparent in the lines expressing PU.2 and PU.1 plus PU.2. (B-G) Total RNA was extracted from duplicate lines and was subjected to quantitative real-time RT-PCR analysis using primers specific for: (B) the 5′ end (exon 2/3) of the murine Pu.1 gene (recognizes Pu.1 only and not Pu.2); (C) the 3′ end (exon 3/4) of Pu.1/Pu.2 (recognizes both Pu.1 and Pu.2); (D) ALAS2; (E) ζ-globin (HBZ); (F) ERMAP; and (G) δ-globin (HBD). In (B and C) the duplicate lines have been shown separately while in (D-G) the average of the two lines has been determined. Levels have been normalized to 18S rRNA and set to 1.0 for the lowest samples. Error bars represent standard error of the mean. *, P <0.05 (Student’s two-tailed t-test) compared to empty vector.