FIG. 5.

Identification of rabbit reticulocyte p32 as α₁-globin. (A) Pir FASTA search for sequence similarity and full-length alignment of two peptide fragment motifs obtained by N-terminal and internal sequencing of p32. HARB, hemoglobin α₁ chain, rabbit. Smith-Waterman score, 155. (B) Addition of BSA to p32-depleted rabbit reticulocyte lysate does not promote E7 mRNA stability. c-myc, eIF-4E, and HPV16 E7 mRNA decay was assayed by using the reticulocyte unbound proteins remaining in solution after incubation with E7 mRNA-activated magnetic beads plus control protein BSA. (C) Quantification of mRNA half-life as in panel B by densitometric analysis. (D) Addition of rabbit hemoglobin to p32-depleted rabbit reticulocyte lysate promotes E7 mRNA stability. c-myc, eIF-4E, and HPV16 E7 mRNA decay was assayed with the reticulocyte unbound proteins remaining in solution after incubation with activated magnetic beads plus rabbit hemoglobin (25 μg). (E) Quantification of mRNA half-life as in panel D by densitometric analysis. ODu, optical density units.