cAMP signalling in mushroom bodies modulates temperature preference behaviour in Drosophila

Abstract

Homoiotherms, for example mammals, regulate their body temperature with physiological responses such as a change of metabolic rate and sweating. In contrast, the body temperature of poikilotherms, for example Drosophila, is the result of heat exchange with the surrounding environment as a result of the large ratio of surface area to volume of their bodies. Accordingly, these animals must instinctively move to places with an environmental temperature as close as possible to their genetically determined desired temperature. The temperature that Drosophila instinctively prefers has a function equivalent to the 'set point' temperature in mammals. Although various temperature-gated TRP channels have been discovered, molecular and cellular components in Drosophila brain responsible for determining the desired temperature remain unknown. We identified these components by performing a large-scale genetic screen of temperature preference behaviour (TPB) in Drosophila. In parallel, we mapped areas of the Drosophila brain controlling TPB by targeted inactivation of neurons with tetanus toxin and a potassium channel (Kir2.1) driven with various brain-specific GAL4s. Here we show that mushroom bodies (MBs) and the cyclic AMP-cAMP-dependent protein kinase A (cAMP-PKA) pathway are essential for controlling TPB. Furthermore, targeted expression of cAMP-PKA pathway components in only the MB was sufficient to rescue abnormal TPB of the corresponding mutants. Preferred temperatures were affected by the level of cAMP and PKA activity in the MBs in various PKA pathway mutants.

Measuring thermal behavior in smaller insects: A case study in Drosophila melanogaster demonstrates effects of sex, geographic origin, and rearing temperature on adult behavior

“…Several efforts have been made to understand this complex regulatory mechanism. [33][34][35][36][37][38][39][40][41]54 With our method and thermal gradient apparatus, we demonstrated that there is significant variation within and among populations in thermal preference, Figure 6. Dispersion of male (filled) and female (open) D. melanogaster along the thermal gradient (T range: 12-32 C).…”

“…Many of these model organisms are used to study molecular and neuronal aspects of thermal sensation and thermal behavior. [33][34][35][36][37][38][39][40][41] In addition, these model organisms can facilitate the evaluation of the effects of climate and climate change at the phenotypic, molecular and species distribution levels. 42,43 The existence of parallel latitudinal clines across multiple continents has been interpreted as adaptation to local climatic conditions.…”

Insulin signalling in mushroom body neurons regulates feeding behaviour inDrosophilalarvae

“…To direct the expression of these constructs to the larval mushroom body neurons, we used two GAL4 lines, 201y-GAL4 and 247-GAL4, identified as having the broadest expression in this structure (Pauls et al, 2010). The expression of 201y-GAL4 and 247-GAL4 is said to be mushroom body specific (Pauls et al, 2010) and as such they have been used in a number of studies addressing the function of this structure in Drosophila larval and adult behaviour (Honjo and FurukuboTokunaga, 2005;Joiner et al, 2006;Hong et al, 2008;Brembs, 2009;Honjo and Furukubo-Tokunaga, 2009;Pauls et al, 2010;Acebes et al, 2011). However, these constructs also label a small number of other neurons in the larval brain and in the case of 247-GAL4, expression in the ventral cord glia has been detected (Pauls et al, 2010).…”

Optical control of zebrafish behavior with halorhodopsin

“…T echnology for the inactivation of specific neurons within an otherwise intact circuit promises to accelerate research into the neural basis of behavior (1)(2)(3)(4)(5)(6)(7)(8). The light-gated chloride pump halorhodopsin (NpHR) from the archaebacterium Natronomonas pharaonis has recently been introduced into neuroscience along with enhanced derivatives (9)(10)(11)(12)(13)(14) and enables superior temporal and spatial control.…”