Flubendiamide regulation

In this study, we demonstrated that the calcium mobilization induced by flubendiamide caused sequential effects on the Ca pump. The pronoimced stimulation of the Ca pump by flubendiamide was closely correlated to insecticidal activity. Further investigation suggested that luminal Ca was an important mediator for the functional co-ordination of RyR and the Ca pump. It is also suggested that this compoimd should provide a promising probe for imderstanding the functional regulations of the insect RyR. 

Flubendiamide (54 ISO-proposed Nihon Nohyaku Co., Ltd./Bayer CropSdence) [125, 126,127] (Fig. 35.13) with a heptafluoro-isopropyl moiety in the anilide part of the molecule (Chapter 34) induces ryanodine-sensitive cytosoUc Ca + transients that were independent of extracellular Ca concentration in isolated neurons from the pest insect Heliothis virescens as well as in transfected CHO cells expressing the RyR from Drosophila mdanogaster. Binding studies on microsomal membranes from H. virescens flight muscle revealed that 54 interacts with a site distinct from the ryanodine binding site and disrupted the Ca + regulation of ryanodine binding by an allosteric mechanism. 

Ryanodine binding to the Heliothis RyR was regulated by both the calcium and the flubendiamide concentrations (Figure 5). At 800 pM [Ca ],... 

Flubendiamide Affected the Calcium Regulation of [ H]Ryanodine Binding... 

High-Affinity Binding of ( H]Flubendiamide was Regulated by Calcium... 

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