The novel pyridazine pyrazolecarboxamide insecticide dimpropyridaz inhibits chordotonal organ function upstream of TRPV channels.

Background: Pyridazine pyrazolecarboxamides (PPCs) are a novel insecticide class discovered and optimized at BASF. Dimpropyridaz is the first PPC to be submitted for registration and controls many aphid species as well as whiteflies and other piercing-sucking insects.

Results: Dimpropyridaz and other tertiary amide PPCs are proinsecticides that are converted in vivo into secondary amide active forms by N-dealkylation.

Differentially timed extracellular signals synchronize pacemaker neuron clocks.

Synchronized neuronal activity is vital for complex processes like behavior. Circadian pacemaker neurons offer an unusual opportunity to study synchrony as their molecular clocks oscillate in phase over an extended timeframe (24 h). To identify where, when, and how synchronizing signals are perceived, we first studied the minimal clock neural circuit in Drosophila larvae, manipulating either the four master pacemaker neurons (LNvs) or two dorsal clock neurons (DN1s).

Analysis of functional neuronal connectivity in the Drosophila brain.

Drosophila melanogaster is a valuable model system for the neural basis of complex behavior, but an inability to routinely interrogate physiologic connections within central neural networks of the fly brain remains a fundamental barrier to progress in the field. To address this problem, we have introduced a simple method of measuring functional connectivity based on the independent expression of the mammalian P2X2 purinoreceptor and genetically encoded Ca(2+) and cAMP sensors within separate genetically defined subsets of neurons in the adult brain. We show that such independent expression is capable of specifically rendering defined sets of neurons excitable by pulses of bath-applied ATP in a manner compatible with high-resolution Ca(2+) and cAMP imaging in putative follower neurons.

Reciprocal cholinergic and GABAergic modulation of the small ventrolateral pacemaker neurons of Drosophila's circadian clock neuron network.

The relatively simple clock neuron network of Drosophila is a valuable model system for the neuronal basis of circadian timekeeping. Unfortunately, many key neuronal classes of this network are inaccessible to electrophysiological analysis. We have therefore adopted the use of genetically encoded sensors to address the physiology of the fly's circadian clock network.

Functional conservation of clock output signaling between flies and intertidal crabs.

Intertidal species have both circadian and circatidal clocks. Although the behavioral evidence for these oscillators is more than 5 decades old, virtually nothing is known about their molecular clockwork. Pigment-dispersing hormones (PDHs) were originally described in crustaceans.