Binding of cis- and trans-dichlorodiammineplatinum(II) to the nucleosome core

Journal Article · Sat Dec 01 04:00:00 EST 1979 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.76.12.6091· OSTI ID:5266133

Lippard, S J ^[1]; Hoeschele, J D

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1. Medical Research Council Lab. of Molecular Biology, Cambridge, England

The binding of the antitumor drug cis-dichlorodiammineplatinum(II) and its inactive trans isomer with the nucleosome core particle has been investigated. Kinetic studies show that platinum binding increases with incubation time, from a few bound platinum atoms per nucleosome core in the first 0.5 h to 40 to 50 after 40 h. There is no crosslinking or dissociation of nucleosome cores upon platinum binding, as revealed by sedimentation velocity measurements. Electrophoresis through 0.1% sodium dodecyl sulfate/18% polyacrylamide gels after platinum binding reveals striking differences in the DNA and protein band patterns for the two isomers. cis-Dichlorodiammineplatinum(II) binds first to the DNA, retarding and spreading its migration in the gel. A comparison study with the 146-base-pair nucleosome core DNA showed the binding to be little affected by the presence of the histone octamer. The trans complex, on the other hand, produces DNA-histone and histone-histone crosslinks that only appear for the cis isomer after long incubation times. The protein-protein crosslinks were reversed by soaking the gel in cyanide solution to form (Pt(CN)/sub 4/)/sup -2/. Subsequent two-dimensional gel electrophoresis revealed that trans-dichlorodiammineplatinum(II) forms specific crosslinks between histone protein pairs H3 and H2a and H2b and H4 in the nucleosome core. The occurrence of DNA-protein crosslinks was demonstrated by treating the platinum/nucleosome core reaction mixtures with a protease or with nucleases prior to electrophoresis and observing changes in the gel patterns. Platinum was located in the gels through autoradiography using /sup 195m/Pt-labeled complexes.

• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5266133
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 76:12; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

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550600 -- Medicine
59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
ANTINEOPLASTIC DRUGS
BIOCHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHROMATIN
COMPLEXES
DAYS LIVING RADIOISOTOPES
DNA
DRUGS
EVEN-ODD NUCLEI
HEAVY NUCLEI
HISTONES
INTERNAL CONVERSION RADIOISOTOPES
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOMERS
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
NUCLEI
NUCLEIC ACIDS
NUCLEOSOMES
ORGANIC COMPOUNDS
PLATINUM 195
PLATINUM COMPLEXES
PLATINUM ISOTOPES
POLYMERIZATION
PROTEINS
RADIOISOTOPES
REACTION KINETICS
STABLE ISOTOPES
STEREOCHEMISTRY
TRACER TECHNIQUES
TRANSITION ELEMENT COMPLEXES