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Fatty acid amides (FAAs) are known elicitors that induce plants to release volatile compounds that, in turn, attract foraging parasitoids. Since the discovery of volicitin [N-(17-hydroxylinolenoyl)-L-glutamine] in the regurgitant of larval Spodoptera exigua, a series of related FAAs have been identified in several other species of lepidopteran caterpillars. We screened 13 non-lepidopteran insects for the presence of FAAs and found that these compounds were present in adults of two closely related cricket species, Teleogryllus taiwanemma and T. emma (Orthoptera: Gryllidae), and larvae of the fruit fly, Drosophila melanogaster (Diptera: Drosophilidae). When analyzed by liquid chromatography/mass spectrometry-ion trap-time-of-flight (LCMS-IT-TOF), the gut contents of both crickets had nearly identical FAA composition, the major FAAs comprising N-linolenoyl-L-glutamic acid and N-linoleoyl-L-glutamic acid. There were also two previously uncharacterized FAAs that were thought to be hydroxylated derivatives of these glutamic acid conjugates, based on their observed fragmentation patterns. In addition to these four FAAs containing glutamic acid, N-linolenoyl-L-glutamine and a small amount of volicitin were detected. In D. melanogaster, N-linolenoyl-L-glutamic acid and N-linoleoyl-L-glutamic acid were the major FAAs found in larval extracts, while hydroxylated glutamic acid conjugates, volicitin and N-linolenoyl-L-glutamine, were detected as trace components. Although these FAAs were not found in ten of the insects studied here, their identification in two additional orders of insects suggests that FAAs are more common than previously reported and may have physiological roles in a wide range of insects besides caterpillars.

Serotonin (5-HT) and the 5-HT receptor during development are known to modulate anxiety and depression in later life. However, the brain mechanisms linking the postnatal 5-HT system and adult behavior remain unknown. Here, we examined the effects of pharmacological 5-HT receptor activation during the postnatal period on anxiety and depression-like behavior in adult BALB/c male mice. To elucidate the underlying mechanisms, we measured mRNA expression of the 5-HT receptor, brain-derived neurotrophic factor (BDNF), GABA receptor subunits, and AMPA receptor subunits in the medial prefrontal cortex (mPFC), amygdala, and hippocampus. Treatment with the selective 5-HT reuptake inhibitor (fluoxetine) and 5-HT receptor agonist (8-OH-DPAT) during the postnatal period decreased anxiety-like behavior in adulthood, whereas only 8-OH-DPAT treatment increased depression-like behavior. Concomitantly with the behavioral effects, postnatal treatment with fluoxetine and 8-OH-DPAT decreased the mRNA expression of the GABA receptor α3 subunit in the mPFC and ventral hippocampus in adulthood, while 8-OH-DPAT, but not fluoxetine, decreased the mRNA expression of the 5-HT receptor and BDNF in the mPFC and the GABA receptor α2 subunit in the mPFC and ventral hippocampus. On the basis of the correlative changes between behavior and mRNA expression, these results suggest that the GABA receptor α3 subunit in the mPFC and ventral hippocampus may regulate anxiety-like behavior. In contrast, depression-like behavior may be regulated by the 5-HT receptor and BDNF in the mPFC and by the GABA receptor α2 subunit in the mPFC and ventral hippocampus. In summary, activation of the 5-HT receptor during the postnatal period may reduce anxiety levels, but increase depression levels during adulthood via different multiple molecules in the mPFC and ventral hippocampus.

Mercury pollution is a worldwide problem in environments, resulting primarily from its industrial use in bleaching operations, as a catalyst, as a pigment in paints, and in the mining of gold. The effects of this heavy metal on the ecosystem and human health are growing concerns. Decontamination of mercury in the sediment and soil around industrial plants has been a challenge for a long time. Unfortunately, numerous sites contaminated with mercurials have not been remediated because of the high costs of dredging and landfilling.2) Phytoremediation, using plants to extract and/or sequester mercurials, is often regarded as a relatively inexpensive and efficient way of cleaning up the mercury-contaminated sites.Recently, with advances in biotechnology, phytoremediation utilizing specific plants to remove mercurials from contaminated sites has become one of the most rapidly developing fields for environmental restoration. Several studies have successfully integrated bacterial mer-genes into plant genome to create superior plants for phytoremediation of mercurial contaminated sites, based on the merA-mediated mercury reduction and volatilization mechanism.3-8) However, phytovolatilization of mercurials mediated by bacterial merA gene from the polluted sites would still cause public anxiety because of the release of mercury vapor into the ambient air that will redistribute in the ecosphere and be recycled to environment. To help solve this environmental problem, a new mercury-scavenging mechanism that can be expressed in plant cells and accumulate mercury from contaminated sites without releasing mercury vapor into the ambient air is required in place of the merA-mediated mercury reduction mechanism.In the previous papers, we reported that expression of ppkspecified polyphosphate (polyP) in a genetically engineered Escherichia coli strain resulted in significantly increased the bioaccumulation of Hg 2ϩ from simulated and actual wastewaters, and protected the bacterial cells from the toxic accumulated Hg 2ϩ . [9][10][11] In theory, plants engineering expression of polyP would also reduce mercury toxicity and accumulate more mercury from the polluted sites. As expected, we found that tobacco plant genetically engineered to express bacterial polyP was more resistant to Hg 2ϩ than its wild-type progenitors.12) The transported Hg 2ϩ seemed to be converted to a less toxic molecule, probably via chelation formation with ppk-specific polyP in the tobacco tissues just as the fact previously described in a bacterial system. 9,10) From these results we communicated that expression of ppk-specific polyP in transgenic tobacco may provide an ecologically compatible approach for environmental phytoremediation of mercury pollution in soils. However, the feasibility of ppk-specific polyP for phytoremediation of mercury had not uncovered. In this study, the ability of ppk-transgenic tobacco to accumulate mercury from the contaminated sites was investigated and the feasibility of this engineered tobacco for environmental remediation of ...