Laboratory of Insect Physiology
We study a humoral control of important physiological processes in the insect body, which include the issue of homeostasis of physiological and biochemical processes in metabolism, digestive processes and anti-stress reactions induced by various stressors including insecticides, pathogens and natural toxins. Among the controlling factors, we focus on the function of adipokinetic hormones and biogenic amines, led by dopamine. For this research we use a wide choice of classical and advanced physiological, biochemical and molecular biology methods. They include chromatographic techniques (HPLC and FPLC), electrophoretic methods, immunomethods (ELISA and Western blotting), metabolic and physiological methods (oxide consumption and carbon dioxide production, monitoring of locomotion), basic methods of molecular biology (RNAi, PCR, q-RT-PCR), microscopic techniques (electron and confocal microscope) and a number of various biochemical assays using spectrophotometric determinations (enzyme reactions, oxidative stress, determination of metabolites, etc.). As the main model insect species we use the firebug Pyrrhocoris apterus and fruit fly Drosophila melanogaster, and to a lesser extent also the migratory locust Locusta migratoria, American cockroach Periplaneta americana, and honeybee Apis mellifera.
Current research projects
A functional analysis of physiological effects of Q-tRNA modification on dopamine homeostasis and stress response in Drosophila melanogaster
We explore links between dopamine homeostasis, its participation in stress response and dysfunctions that can lead to neurodegenerative diseases. We evaluate the physiological role of defects in Q-tRNA (queuosine-transfer RNA that is important for dopamine synthesis) on dopamine homeostasis. We use UAS-GAL4 system activating gene expression in D. melanogaster followed by various methods assessing effect of changes of dopamine level on brain functions. The effects of the stress is monitored at the behavioural and physiological levels in an age dependent manner.
PI: Andrea Bednářová, Zdeňka Svobodová
Endocrine control of stress situations
The project deals with a study of the physiological processes in insect body, which are switched on by peptides from the adipokinetic hormone (AKH) family as an immediate reaction on stress situations. The study is focussed on mobilization of anti-oxidative stress reactions including their mode of action on biochemical level, and on role of AKH in defence reactions against pathogens as entomopathogenic nematodes and fungi, and the venom from a parasitic wasp Habrobracon hebetor. Further, the project involves also a study of AKH mechanisms, which stimulate the pathogens to intensification of their efficacy on the host organism.
PI: Dalibor Kodrík
Neurohormonal control of digestion
The aim of the project is to understand the mechanisms by which AKHs stimulate the food intake and activity of digestive enzymes. The project monitors activity of basic and less common insect digestive enzymes (amylases, lipases, proteases, polygalacturonases) in stressful situations and the effect of AKHs on them.
PI: Dalibor Kodrík, Konstantin Vinokurov