Studies of human histone messenger RNA. I. Methods for the isolation and partial characterization of RNA fractions containing human histone message from HeLa S3 polyribosomes.

Large quantities of nonpolyadenylated [poly(A(-))] 4 to 18 S RNA were isolated from the polyribosomes of S phase HeLa S3 cells and were fractionated into multiple discrete RNA components by continuous elution preparative electrophoresis. Previous studies have shown that treatment os S phase HeLa cells with cytosine arabinoside inhibits DNA replication and causes translatable histone messenger RNA (mRNA) species to disappear from cytoplasmic polyribosomes (Borun, T. W., Scharff, M.D., and Robbins, E. (1967) Proc. Natl. Acad. Sci. U.S.A. 58, 1977-1983; Gallwitz, D., and Mueller, G. C. (1969) J. Biol. Chem. 244, 5948-5952; Borun, T. W., Gabrielli, F., Ajiro, K., Zweidler, A., and Baglioni, C. (1975) Cell 4, 59-67; Gallwitz, D. (1975) Nature 257, 247-248). In the present study it was found that cytosine arabinoside treatment does not appreciably affect major 7.5 to 8 S RNA species but does cause the disappearance of 8.6 to 13 S RNA components from preparative electrophoresis elution profiles of S phase polyribosomal 4 to 18 S RNA. Base ratio analysis of the 8.6 to 13 S putative histone mRNA species indicates that they are GC-rich but not like the HeLa 18 or 28 S rRNA in base composition.