J Korean Med Sci.  1990 Sep;5(3):127-135. 10.3346/jkms.1990.5.3.127.

Studies on rat liver nuclear DNA damaged by chemical carcinogen (3'-Me DAB) and AP DNA endonuclease. I. Purification and some properties of AP DNA endonucleases in rat liver chromatin

• Kim YS
• Kim JW
• Lee SE
• Oh SH

• KMID: 1421490
• DOI: http://doi.org/10.3346/jkms.1990.5.3.127

Abstract

Three kinds of apurinic/apyrimidinic (AP) DNA endonuclease, APcI, APcII, APcIII, were purified from rat liver chromatin through 1M KCl extraction, DEAE-trisacryl ion exchange chromatography. Sephadex G-150 gel filtration and AP DNA cellulose affinity chromatography. Activities of the purified APcI, APcII and APcIII were 62.5, 83.3 and 52.0 EU/mg of protein, respectively. Molecular weights of APcI, APcII and APcIII, each consisting of a single polypeptide, were 30,000, 42,000 and 13,000, and isoelectric points of them were 7.2, 6.3 and 6.2, respectively. Three enzymes showed different substrate specificities; APcI acted only on AP DNA, and APcII acted on both AP DNA and UV DNA, while APcIII acted on 3'-methyl-4-monomethylaminoazobenzene (3'-Me MAB) DNA adduct as well as AP DNA and UV DNA. These results indicate that three kinds of AP DNA endonuclease present in rat liver chromatin have structural and functional diversities.

Keyword

AP DNA endonuclease; Purification; Rat liver chromatin

MeSH Terms

Animals
Carcinogens
Chromatin/*enzymology
DNA Damage/*physiology
DNA-(Apurinic or Apyrimidinic Site) Lyase
Deoxyribonuclease IV (Phage T4-Induced)
Electrophoresis, Polyacrylamide Gel
Endodeoxyribonucleases/*isolation & purification/metabolism
Isoelectric Focusing
Liver/drug effects/*enzymology
Male
Rats
Rats, Inbred Strains
Substrate Specificity
p-Dimethylaminoazobenzene
Carcinogens
Chromatin
p-Dimethylaminoazobenzene
Endodeoxyribonucleases
Deoxyribonuclease IV (Phage T4-Induced)
DNA-(Apurinic or Apyrimidinic Site) Lyase