The molecular mechanism of interaction of Et3Pb+ with tubulin

• Published in: FEBS letters Vol. 174; no. 1; pp. 128 - 131
• Main Authors: Faulstich, H., Stournaras, C., Doenges, K.H., Zimmermann, H.-P.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 20.08.1984
• Subjects: 2,4-dinitrophenylglutathionyl disulfide; 5,5'-dithiobis(2-nitrobenzoic acid); Actins - metabolism; Animals; Biological and medical sciences; Brain - metabolism; Cell structures and functions; Cytoskeleton, cytoplasm. Intracellular movements; Disulfide; DNPSSG; DTNB; Et3Pb; Fundamental and applied biological sciences. Psychology; Lead - pharmacology; Macromolecular Substances; Microtubule assembly; microtubule-associated proteins; Microtubules - metabolism; Microtubules - ultrastructure; Molecular and cellular biology; Muscles - metabolism; Neurotoxins - pharmacology; Organometallic Compounds - pharmacology; Protein Binding; Rabbits; Sulfhydryl group; Swine; Thiol reagents; Triethyllead chloride; triethyllead ion; Tubulin - metabolism; Vertebrata; Mammalia; Tubulin; Molecular assembly; Toxicity; Polymerization; Cytoskeleton; Brain (Vertebrata); Artiodactyla; Microtubule; Ungulata; Pig
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(84)81090-X

Triethyllead ion (Et3Pb+) was found to interact with 2 out of 18 thiol groups present in tubulin dimers. Specificity of the interaction was shown by the high affinity of Et3Pb+ to tubulin, by the fact that the 16 residual thiol groups in tubulin remained unaffected, and by the observation that other proteins with exposed thiol groups, e.g., actin, did not react with Et3Pb+. After complexation of the two thiol groups, tubulin in vitro had lost its capability for microtubule assembly. Likewise, polymerized tubulin disassembled on addition of the lead compound.