Isolation of mammalian pol beta type DNA polymerase in shoot tips of germinated seedlings of IR-8 rice (Oryza sativa L.)

Biochem Mol Biol Int. 1996 May;39(1):117-26. doi: 10.1080/15216549600201121.


A single polypeptide of approx. 67 kDa mol.wt. with DNA polymerase activity has been chromatographically purified from shoot tips of 72 hr. grown germinated seedlings of rice (Oryza IR-8). An approx. 4800 fold enrichment of specific activity was measured by the incorporation of 3H-dTMP into trichloroacetic acid insoluble fraction, using activated calf thymus DNA as template-primer. The enzyme uses different types of DNA but not RNA as a template. The enzyme requires Mg+2, high KCl, and is highly sensitive to dideoxyribonucleoside triphosphate but is unaffected by aphidicolin, suggesting a plant counterpart of mammalian DNA polymerase beta. Replication of M13mp18 single stranded DNA by extension of 5'32P-labeled 17-mer primer(-40) showed distributive type of DNA synthesis by the rice DNA polymerase beta, which is a characteristic feature of mammalian DNA polymerase beta.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Polymerase I / isolation & purification*
  • Germination / physiology
  • Oryza / enzymology*
  • Plant Shoots / enzymology*
  • Seeds / enzymology


  • DNA Polymerase I