Stabilization of hepatic colchicine-binding activity by organic acids

Area of Science:

• Biochemistry
• Cell Biology

Background:

• Hepatic tubulin exhibits distinct [3H]colchicine binding properties compared to brain tubulin.
• Microtubule-derived liver tubulin shows rapid loss of colchicine-binding activity.
• Quantitative tubulin assays are hindered by unstable binding sites in liver tubulin.

Purpose of the Study:

• To investigate the stabilizing effects of organic acids on liver tubulin.
• To evaluate glutamate and glucose 1-phosphate as protecting agents for liver tubulin in [3H]colchicine binding assays.

Main Methods:

• Testing the stabilizing effect of glutamate and glucose 1-phosphate on liver tubulin under [3H]colchicine binding conditions.
• Assessing the protective capacity of these agents against loss of binding activity when purified brain tubulin interacts with liver supernatants.

Main Results:

• Glutamate and glucose 1-phosphate were found to stabilize liver tubulin.
• These organic acids prevented the rapid loss of colchicine-binding activity in liver tubulin.
• The agents also protected purified brain tubulin from inactivation by liver supernates.

Conclusions:

• Organic acids, glutamate and glucose 1-phosphate, can modify the solution stability of liver tubulin.
• These compounds show potential as analytical tools to improve [3H]colchicine binding assays for liver tubulin quantification.