, 1998). Moreover, concerning spatial learning, the insect mushroom body is equivalent to the vertebrate hippocampus (Capaldi et al., 1999), where the zinc is more abundant in the brain (Slomianka, 1992 and Zimmer, 1973). Our findings show for the first time that histochemically reactive zinc, as determined by the Neo-Timm method, CX-5461 is present in specific regions of the honey bee brain. The optical lobe is involved in the visual and sensorial activities, while the mushroom bodies constitute the main memory center where complex local synaptic circuits have been previously described (Kamikouchi et al., 1998). Therefore, the myosin-Va localization data indicate that
it is widely distributed in the brain. This finding agrees with previous reports, which have used myosin-Va as a neuronal marker for immunohistochemical studies of the honey bee brain (Calabria et al., 2010) and to map brain structures in vertebrates (Martins et al., 1999 and Tilelli et al., 2003). In Panobinostat purchase general, DYNLL1/LC8 and myosin-Va showed similar patterns of immunolocalization. Differences in the staining patterns were found in the monopolar neurons of the fenestrated layer and in the outer and inner chiasms of the optical lobe, whereas myosin-VI and synaptophysin were localized to the retina and monopolar neuron of the lamina.
Moreover, zinc was amply distributed on the long fibers of the lamina and fenestrated layer, which were also enriched in DYNLL1/LC8 and myosin-Va. The cells of the optical lobe subregions have been shown to be immunoreactive to the serotonin, GABA and catecholamine neurotransmitters (Meyer et al., 1986 and Nassel et al., 1986). Although our data for the antennal lobe indicated that myosin-VI and synaptophysin were restricted to the interneurons, myosin-Va was only found in the fiber terminal fields of the glomeruli, as also revealed for the zinc immunostaining. Digestive enzyme These findings can be explained by the composition and function of
this neuropil, which transmits information to the mushroom bodies and other lobes (Galizia and Menzel, 2000, Kloppenburg, 1995, Menzel and Muller, 1996 and Nassel et al., 1986). The results obtained in our study indicated that myosin-Va is present in the honey bee nervous system in the larvae and adult castes and subcastes. We also showed that DYNLL1/LC8, and myosins -IIb, -VI and -IXb are present in the adult brain, as well as SNARE proteins, such as CaMKII, clathrin, syntaxin, SNAP25, munc-18, synaptophysin and synaptotagmin. Our study revealed increased expression levels of myosin-Va classically associated with neuron function and plasticity when we challenged honey bee brains with melittin, a naturally occurring bee toxin, and NMDA, a synthetic excytotoxin, and open perspective of new studies to determine the mechanisms underlying myosin-Va over-expression and if this is a pro-survival response.