Expression of a mutant DNA topoisomerase II in CCRF-CEM human leukemic cells selected for resistance to teniposide

Journal Article · Sun Sep 01 00:00:00 EDT 1991 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.88.17.7654· OSTI ID:5822480

Bugg, B Y; Danks, M K; Beck, W T ^[1]; Suttle, D P ^[2]

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1. St. Jude Children's Research Hospital, Memphis, TN (United States)
2. St. Jude Children's Research Hospital, Memphis, TN (United States) Veterans Affairs Medical Center, Memphis, TN (United States)

Nuclear extracts from teniposide (VM-26)-resistant sublines of the human leukemic cell line CCRF-CEM have decreased levels of DNA topoisomerase II catalytic activity and decreased capacity to form drug-stabilized covalent protein-DNA complexes. The ATP concentration required for equivalent activity in a DNA-unknotting assay is 2- to 8-fold higher in nuclear extracts from drug-resistant cell lines as compared with the parental line. When adenosine 5{prime}-({beta},{gamma}-imido)triphosphate is substituted for ATP in complex-formation assays, no significant change is seen with drug-sensitive cells, but a 50-65% reductions is seen with VM-26-resistant cells. Collectively, these results indicate that an alteration in ATP binding may be involved in the resistance phenotype. Therefore, the authors identified regions of the topoisomerase II sequence that conform to previously identified nucleotide-binding sites. Starting with cDNA as the template they determined the sequence of the topoisomerase II mRNA surrounding these sites by sequencing DNA fragments produced by the polymerase chain reaction.

• OSTI ID: 5822480
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States) Vol. 88:17; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANTINEOPLASTIC DRUGS
BIOLOGICAL EFFECTS
DISEASES
DNA
DNA BASE TRANSITIONS
DNA POLYMERASES
DNA SEQUENCING
DRUGS
ENZYMES
IMMUNE SYSTEM DISEASES
ISOMERASES
LEUKEMIA
MESSENGER-RNA
MUTANTS
NEOPLASMS
NUCLEIC ACIDS
NUCLEOTIDYLTRANSFERASES
OLIGONUCLEOTIDES
ORGANIC COMPOUNDS
PHOSPHORUS-GROUP TRANSFERASES
POLYMERASES
PROTEINS
RECOMBINANT DNA
RNA
STRUCTURAL CHEMICAL ANALYSIS
TRANSFERASES
TUMOR CELLS