Abstract
Since 2006, a syndrome known as “colony collapse syndrome” (or CCD) has been responsible for an average mortality of 50% (in extreme cases up to 90%) of bee colonies in certain regions of the world. Although of multifactorial origin, the intensive spraying of insecticides shows a major role in the mortality of pollinators. However, in the absence of protection, 30 to 40% of the world's crops would be destroyed by diseases and pest insects. In 2009, these insects have caused by themselves an average loss of 14%. The fight against these insects is therefore essentially based on the application of synthetic insecticides, whose massive use of which has quickly led to numerous deleterious effects on non-target insects but also on the environment or human health. The acute toxicity of the different classes of insecticidal compounds occurs through their actions on the ion channels. However, the sensitivity of bees to these compounds remains to be determined, in order to consider the development of alternatives to crop protection methods. Among the main objectives of this thesis project, were i) the characterization of the ion channels of Apis mellifera and pest insects (aphid Acyrthosiphon pisum, and varroa Varroa destructor) by the technique of two-electrode voltage clamp electrophysiology, ii) transcriptomic and proteomic analysis of different spider venoms in order to provide molecular tools to accurately decipher the pharmacology and roles of the main ion channel subtypes in the neurobiology of honeybees, but also identify new insecticidal molecules selective for pest insects.