Rho GTPase activity in the honey bee mushroom bodies is correlated with age and foraging experience

Neuroscience Program, Wake Forest University, Graduate School of Arts and Sciences, Winston-Salem, NC 27157, USA.
Journal of insect physiology (Impact Factor: 2.47). 11/2011; 58(2):228-34. DOI: 10.1016/j.jinsphys.2011.11.009
Source: PubMed


Foraging experience is correlated with structural plasticity of the mushroom bodies of the honey bee brain. While several neurotransmitter and intracellular signaling pathways have been previously implicated as mediators of these structural changes, none interact directly with the cytoskeleton, the ultimate effector of changes in neuronal morphology. The Rho family of GTPases are small, monomeric G proteins that, when activated, initiate a signaling cascade that reorganizes the neuronal cytoskeleton. In this study, we measured activity of two members of the Rho family of GTPases, Rac and RhoA, in the mushroom bodies of bees with different durations of foraging experience. A transient increase in Rac activity coupled with a transient decrease in RhoA activity was found in honey bees with 4 days foraging experience compared with same-aged new foragers. These observations are in accord with previous reports based on studies of other species of a growth supporting role for Rac and a growth opposing role for RhoA. This is the first report of Rho GTPase activation in the honey bee brain.

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Available from: Susan E Fahrbach, Jan 06, 2014
    • "For experience-dependent neuronal plasticity in the MB calyx, stimulation of muscarinic–type cholinergic receptors was shown to mimic foraging-related sensory exposure indicating that it is an associated and necessary factor (Ismail et al., 2006; Dobrin et al., 2011). Those plastic changes were suggested to be initiated by Rho GTPases, small monomeric G proteins, involved in the reorganization of the neuronal cytoskeleton (Dobrin and Fahrbach, 2012). A further candidate for mediating MG plasticity is calcium calmodulin depenent protein kinase II (CaMKII), which is highly localized in a major subpopulation of KCs (Kamikouchi et al., 2000; Pasch et al., 2011). "
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