FIG. 1.

hα-globin mRNA localizes to the polysome fraction of K562 cells. A clarified (S20) cytoplasmic extract from log-growth K562 was pelleted through a 30% sucrose cushion to separate prepolysome supernatant (S130) and polysomal (P) pellet fractions. hα-globin and GAPDH mRNAs were detected by RPA. The positions of the protected bands corresponding to GAPDH and α-globin are noted. The band above α-globin corresponds in size to the primary α-globin transcript and may be detecting contaminant genomic DNA. A 25-nt DNA ladder is shown (M).