Okadaic acid induces the rapid and reversible disruption of the neurofilament network in rat dorsal root ganglion neurons

• Published in: Biochemical and biophysical research communications Vol. 186; no. 1; p. 524
• Main Authors: Sacher, M G, Athlan, E S, Mushynski, W E
• Format: Journal Article
• Language: English
• Published: United States 15-07-1992
• Subjects: Animals; Blotting, Western; Cells, Cultured; Detergents; Electrophoresis, Gel, Two-Dimensional; Electrophoresis, Polyacrylamide Gel; Embryo, Mammalian; Ethers, Cyclic - pharmacology; Fluorescent Antibody Technique; Ganglia, Spinal - metabolism; Ganglia, Spinal - ultrastructure; Intermediate Filaments - drug effects; Intermediate Filaments - ultrastructure; Neurofilament Proteins - isolation & purification; Neurofilament Proteins - metabolism; Neurons - drug effects; Neurons - metabolism; Neurons - ultrastructure; Octoxynol; Okadaic Acid; Phosphoprotein Phosphatases - antagonists & inhibitors; Polyethylene Glycols; Rats
• ISSN: 0006-291X
• DOI: 10.1016/S0006-291X(05)80839-3

Treatment of 15-17 day old dissociated cultures of rat dorsal root ganglia with 1 microM okadaic acid caused a reduction in the mobilities of neurofilament subunits on SDS-polyacrylamide gels, signifying an increase in their phosphorylation levels. When cultures were exposed to okadaic acid for 0.5 hrs and harvested in buffer containing Triton X-100, NF-H was nearly completely redistributed to the detergent- soluble fraction while NF-M and NF-L required a longer exposure to the drug before undergoing a similar shift. This redistribution of subunits corresponded with striking changes in the immunofluorescence staining pattern for neurofilaments. Upon removal of okadaic acid from the culture medium following a 0.5 hr treatment, NF-L and NF-M returned to the Triton X-100 insoluble fraction within 2 hrs while NF-H required 10 hrs for recovery.