Preliminary Study on the Acaricidal Mechanism of Methyl Palmitate to Tetranychus cinnabarinus

Methyl palmitate has showed acaricidal activity to Tetranychus cinnabarinus in our previous studies. However, the acaricidal mechanism of methyl palmitate to T. cinnabarinus is unknown. It was presumed that methyl palmitate may play its acaricidal activity to T. cinnabarinus by interfering the biological function of muscarinic receptors. In our studies, the most important muscarinic receptor subtypes M₁, M₂ and M₃ were detected in the methyl palmitate treated T. cinnabarinus by immunoblotting method. Subsequently, the two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (2D SDS-PAGE) method was used to analyze the change of the protein expression patterns in T. cinnabarinus in response to methyl palmitate treatment to preliminarily discuss its action mechanism. About 19 protein spots with approximately 2-fold increased density, about 31 protein spots with approximately 2- fold reduced density, about 14 disappeared protein spots, and about 13 novel protein spots were detected in the 2D SDS-PAGE gels of the methyl palmitate treated T. cinnabarinus compared to the control. Methyl palmitate may play its acaricidal activity on T. cinnabarinus by affecting muscarinic receptors related signal transduction, and changing the protein expression patterns in T. cinnabarinus.