Characterization of DNA polymerase β mRNA: Cell-cycle and growth response in cultured human cells

Abstract

DNA polymerase β (β-polymerase) is a housekeeping enzyme involved in DNA repair in vertebrate cells. We used a cDNA probe to study abundance of β-polymerase mRNA in cultured human cells. The mRNA level in synchronized HeLa cells, representing different stages of the cell-cycle, varied only slightly. Contact inhibited fibroblasts AG-1522 contained the same level of mRNA as growing cells. The steady-state level of mRNA in fibroblasts is equivalent to 6 molecules per cell. The results indicate that the β-polymerase transcript is "low abundance" and is neither cell-cycle nor growth phase responsive. © 1988 IRL Press Limited, Oxford, England.