Binding of benzo(a)pyrene derivatives to specific proteins in nuclei of intact hamster embryo cells

Journal Article · Thu Oct 01 00:00:00 EDT 1981 · Cancer Res.; (United States)

OSTI ID:5336758

MacLeod, M C ^[1]; Kootstra, A; Mansfield, B K; Slaga, T J; Selkirk, J K

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1. Oak Ridge National Laboratory, TN

In hamster embryo cells incubated for 24 hr with 4 ..mu..m (/sup 3/H)benzo(a)pyrene, a major portion of the nonextractable radioactivity in nuclear preparations copurifies with the protein fraction. When these proteins are analyzed by sodium dodecyl sulfate:polyacrylamide gel electrophoresis, significant variations in the labeling intensities of the various proteins are seen. Control experiments demonstrate that the labeling is due to covalent binding to protein. Histones H3 and H2A are heavily labeled while the other histones of the nucleosome core, H2B and H4, are deviod of radioactivity. Large amounts of label are associated with proteins with mobilities similar to the very lysine-rich histones H1. However, the results of differential extraction experiments suggest that the labeled proteins do not belong to either the H1 or the high-mobility-group class of chromosomal proteins. During 6 hr of inhibition of protein synthesis by cycloheximide, the metabolism of (/sup 3/H)-benzo(a)pyrene, as monitored by high-pressure liquid chromatography, remained normal. Patterns of labeling of nuclear proteins after 3 or 6 hr were identical in the presence and absence of cycloheximide. This finding strongly suggests that binding of benzo(a)pyrene derivatives to nuclear proteins occurs in situ.

• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5336758
• Journal Information: Cancer Res.; (United States), Journal Name: Cancer Res.; (United States) Vol. 41; ISSN CNREA
• Country of Publication: United States
• Language: English

Related Subjects

560301* -- Chemicals Metabolism & Toxicology-- Cells-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANIMALS
ANTI-INFECTIVE AGENTS
ANTIBIOTICS
AROMATICS
BENZOPYRENE
CARCINOGENESIS
CELL CONSTITUENTS
CELL NUCLEI
CHEMICAL BONDS
CONDENSED AROMATICS
CYCLOHEXIMIDE
DRUGS
EMBRYONIC CELLS
FUNGICIDES
HAMSTERS
HYDROCARBONS
LABELLED COMPOUNDS
MAMMALS
METABOLISM
ORGANIC COMPOUNDS
PATHOGENESIS
PESTICIDES
PROTEINS
RODENTS
SENSITIVITY
TRITIUM COMPOUNDS
VERTEBRATES