Direct photoaffinity labeling of tubulin with colchicine

Journal Article · Mon Apr 01 04:00:00 EST 1991 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.88.7.2820· OSTI ID:5583493

Wolff, J; Knipling, L; Cahnmann, H J; Palumbo, G ^[1]

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1. National Institutes of Health, Bethesda, MD (USA)

Ultraviolet irradiation of the ({sup 3}H)colchicine-tubulin complex leads to direct photolabeling of tubulin with low but practicable efficiency. The bulk (70% to greater than 90%) of the labeling occurs on beta-tubulin and appears early after irradiation, whereas {alpha}-tubulin is labeled later. The labeling ratio of {beta}-tubulin to {alpha}-tubulin ({beta}/{alpha} ratio) is reduced by prolonged incubation, prolonged irradiation, urea, high ionic strength, the use of aged tubulin, dilution of tubulin, or large concentrations of colchicine or podophyllotoxin. Glycerol increases the {beta}/{alpha} ratio. Limited data with ({sup 3}H)podophyllotoxin show that it covalently bound with a similar {beta}/{alpha} distribution. Vinblastine, on the other hand, exhibits preferential attachment to {alpha}-tubulin. The possibilities that colchicine binds at the interface between {alpha}-tubulin and {beta}-tubulin, that the drug spans this interface, and that both subunits may contribute to the binding site are suggested.

• OSTI ID: 5583493
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (USA) Vol. 88:7; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
560120 -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALCOHOLS
ALKALOIDS
ANIMALS
ANTIMITOTIC DRUGS
ANTIPYRETICS
AROMATICS
AZAARENES
AZOLES
BIOCHEMICAL REACTION KINETICS
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM DEPRESSANTS
CHEMICAL RADIATION EFFECTS
CHEMISTRY
COLCHICINE
DRUGS
ELECTROMAGNETIC RADIATION
GLYCEROL
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
INDOLES
ISOTOPE APPLICATIONS
KINETICS
LABELLING
MAMMALS
MEMBRANE PROTEINS
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PROTEINS
PYRROLES
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RATS
REACTION KINETICS
RECEPTORS
RODENTS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ULTRAVIOLET RADIATION
VERTEBRATES
VINBLASTINE