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Abstract: Growth-blocking peptide (GBP) is a member of an insect cytokine family with diverse functions including growth and immunity controls. Members of this cytokine family have been reported in 15 species of Lepidoptera, and we have recently identified GBP-like peptides in Diptera such as Lucilia cuprina and Drosophila melanogaster, indicating that this peptide family is not specific to Lepidoptera. In order to extend our knowledge of this peptide family, we purified the same family peptide from one of the tenebrionids, Zophobas atratus, 1 [1] Zophobas atratus Zmc mRNA for cytokine, AB243070. isolated its cDNA, and sequenced it. The Z. atratus GBP sequence together with reported sequence data of peptides from the same family enabled us to perform BLAST searches against EST and genome databases of several insect species including Coleoptera, Diptera, Hymenoptera, and Hemiptera and identify homologous peptide genes. Here we report conserved structural features in these sequence data. They consist of 19–30 amino acid residues encoded at the C terminus of a 73-152 amino acid precursor and contain the motif C-x(2)-G-x(4,6)-G-x(1,2)-C-[KR], which shares a certain similarity with the motif in the mammalian EGF peptide family. These data indicate that these small cytokines belonging to one family are present in at least five insect orders. [Copyright &y& Elsevier]

Feeding activities of animals, including insects, are influenced by various signals from the external environment, internal energy status, and physiological conditions. Full understanding of how such signals are integrated to regulate feeding activities has, however, been hampered by a lack of knowledge about the genes involved. Here, we identified an anorexic Drosophila melanogaster mutant (GS1189) in which the expression of a newly identified gene, Anorexia (Anox), is mutated. In Drosophila larvae, Anox encodes an acyl-CoA binding protein with an ankyrin repeat domain that is expressed in the cephalic chemosensory organs and various neurons in the central nervous system (CNS). Loss of its expression or disturbance of neural transmission in Anox-expressing cells decreased feeding activity. Conversely, overexpression of Anox in the CNS increased food intake. We further found that Anox regulates expression of the insulin receptor gene (dInR); overexpression and knockdown of Anox in the CNS, respectively, elevated and repressed dInR expression, which altered larval feeding activity in parallel with Anox expression levels. Anox mutant adults also showed significant repression of sugar-induced nerve responses and feeding potencies. Although Anox expression levels did not depend on the fasting and feeding states cycle, stressors such as high temperature and desiccation significantly repressed its expression levels. These results strongly suggest that Anox is essential for gustatory sensation and food intake of Drosophila through regulation of the insulin signaling activity that is directly regulated by internal nutrition status. Therefore, the mutant strain lacking Anox expression cannot enhance feeding potencies even under starvation. [ABSTRACT FROM AUTHOR]

Abstract: The lattice energies for the enantiopure and racemic crystals of α-(trifluoromethyl)lactic acid were calculated by a combination of the DFT calculations with the periodic boundary condition and the MP2 calculations of the interactions with neighboring molecules. The lattice energies calculated for the two crystals (−16.56 and −17.35kcal/mol, respectively) show that the racemic crystals are thermodynamically more stable, although the racemic crystals sublime faster than the enantiopure crystals. The calculations suggest that the relative thermodynamic stability is not the cause of the faster sublimation rate of the racemic crystals compared with the enantiopure crystals. Although the crystals have hydrogen-bonding networks, the dispersion interactions contribute to the lattice energies significantly. The MP2 calculations for the evaluation of the dispersion interactions with the neighboring molecules are important for an accurate evaluation of the lattice energies. The relative thermodynamic stability of the two crystals is not determined solely by the hydrogen bonds. The interactions with other neighboring molecules also play important roles in determining the relative stability. We demonstrate that the geometry optimization is essential for an accurate evaluation of the lattice energy by the first principle calculation. The interaction energies calculated using the structure by X-ray diffraction often have large errors. [Copyright &y& Elsevier]

Abstract: To examine the mechanism by which insects change their food preferences, a simple method was developed to measure their preferences. By using this method, we demonstrated preference of Drosophila melanogaster larvae of the y control strain for a food based on soybeans over one based on cornmeal. We then screened for mutant strains with food preferences clearly different from the control y strain, using the Gene Search collection of P-element insertions (GS strains). Among 380 GS strains screened using an assay plate-containing soybean and corn tastants, we identified one mutant, GS1189 that did not show any preference for either of the foods. Further behavioral assays indicated that the GS1189 larvae could have impaired olfactory and gustatory systems. The fact that the CG33071 gene expression was inactivated by the P-element insertion in the GS1189 strain, and that reversion of this gene completely recovered the normal food preference, indicates that this gene contributes to the control of food preferences in Drosophila larvae. [Copyright &y& Elsevier]

Abstract: It is widely known that addition of a radical species to the sulfur atom of a reduced sulfur molecule results in formation of a two-center three-electron (2c-3e) bond, but relatively few investigations have been reported for the 2c-3e bond between the NO3 radical and a sulfur molecule. This article presents results of gas-phase DFT and ab initio investigations on the 2c-3e type adducts of the NO3 radical with reduced sulfur molecules. By using correlation consistent basis sets, geometry optimizations at the MP2 and BH&HLYP levels and single-point energy evaluations at the CCSD(T) level were carried out. Our estimates for the dissociation enthalpies (ΔH (298K)) of the 2c-3e S–O bonds in the NO3 radical adducts of the CH3SH, CH3SCH3, and CH3SSCH3 molecules are 7∼10, 15∼16, and 10∼12kcal/mol, respectively, but our calculations suggest that the H2S molecule will not actually form a 2c-3e adduct with the NO3 radical. [Copyright &y& Elsevier]

Abstract: Ab initio and DFT investigations on H2S–OH and (CH3)2S–OH adducts have shown that electron correlation is essential for an accurate description of the two-center three-electron S–O bonds in the adducts. Calculations at the BH&HLYP, B3LYP, MP2, and CCSD(T) levels indicate that the S–O bond in the (CH3)2S–OH adduct is considerably stronger and shorter than that in the H2S–OH adduct. Our best estimate for the dissociation enthalpy at 298K for the S–O bond in the (CH3)2S–OH adduct is 9.0kcal/mol, which is in satisfactory agreement with experimentally derived values. [Copyright &y& Elsevier]

Abstract: The suboesophageal body of insects was identified over a century ago in the silkworm embryo, but its biological function is still unknown. We discovered that this tissue is differentiated in the earliest embryonic stages of the cabbage armyworm and secretes the insect cytokine, growth-blocking peptide (GBP), transiently from 24 to 60h after oviposition when gastrulation is in progress. Over-expression of GBP, achieved by microinjection of the GBP gene driven by a cytomegalovirus (CMV) constitutive promoter, resulted in complex deformities of the procephalon (embryonic head). Severe abnormal phenotypes of the head structure were produced by silencing the GBP expression in the embryo by treating with GBP double-stranded RNA: the procephalon-containing optic lobes diminished and completely separated into bilateral halves. This indicates that GBP secreted from the suboesophageal body plays an essential role in the formation of the procephalic domain during early embryogenesis. The cytokine-induced fusion of bilateral procephalic lobes is thought to be evolutionarily conserved at least in insects, because of the widespread occurrence of the suboesophageal body in insect embryos. [Copyright &y& Elsevier]

Ab initio investigations on the gas-phase reaction pathways for the hydrolytic decomposition of CF2O molecule have indicated that the energy barriers for the reaction channels of CF2O with a single H2O molecule are significantly reduced when an additional H2O molecule is brought into the reaction system. The additional H2O molecule serves as a proton relay acting simultaneously as a proton donor and acceptor in the transition states. These findings may imply that reaction channels in which multiple, at least two, H2O molecules participate will be important for the homogeneous gas-phase hydrolysis of CF2O. [Copyright &y& Elsevier]

Abstract: Ab initio magnetic shielding calculations (GIAO, HF/6-311G**) were performed for five compounds that contain 2-methylenepropane-1,3-diyl (so-called isobutenylene) group. By comparison among methyl-, phenyl-, and naphthyl-bearing compounds, the roles of each substituent in the stability of conformation and in the magnetic shielding were elucidated. The shielding constant of the olefinic protons showed an obvious dependence on the conformation of CC–C moiety. The conformational dependence was analyzed in terms of the shielding and deshielding effects of the ring current of aromatic substituents, leading to a general formulation for conformation-dependent shielding of olefinic protons. The results were utilised to interpret the chemical shifts observed for several macrocyclic compounds. [Copyright &y& Elsevier]

Abstract: Irradiation of the crystal of 1-perfluorophenyl-6-phenyl-1,3,5-hexatriene (1), the 1:1 cocrystal of 1,6-diphenyl-1,3,5-hexatriene (2) and 1,6-bis(perfluorophenyl)-1,3,5-hexatriene (3) (2/3), and crystal 3 gave a mixture of dimer, trimer and higher oligomers that was soluble in common organic solvents. The highest molecular weight was 5000–8000 (the degree of polymerization=15–20). The order of reactivity was 1 > 2/3 ≫ 3. The reaction of 1 was relatively efficient compared to typical organic crystals. The conversion reached 100% after 3h irradiation. In each case, the regio- and stereoselectivity in the photodimerization was high, whereas in the formation of trimer and higher oligomers, the selectivity was much lower. The main dimer was spectroscopically identified to be the face-to-face dimer formed by the [2+2] cycloaddition at the 1,2-position of the triene double bonds. The photoproducts from 1 and 2/3 were amorphous, as evidenced by powder X-ray diffraction and polarizing optical microscopy. This is probably due to the nonplanar and bulky structures of the cyclobutane products. The photodimerization and polymerization are considered to be non-topochemical reactions. [Copyright &y& Elsevier]

• The Bu 4 N+-assisted Norrish-Yang cyclization affords trans -dihydrobenzofuranols. • Cation-pi interactions increase the population of syn -conformers of substrates. • A new type of organocatalyst accelerates the Norrish-Yang cyclizations. The tetrabutylammonium-accelerated Norrish-Yang cyclization of 2-ethoxycarbonylmethyloxy- and 2-cyanomethyloxyacetophenones afforded trans -dihydrobenzofuranols in good stereoselectivities through cation-π interactions between the ammonium and the carbonyl and cyano groups. Furthermore, a new type of organocatalyst possessing both conformation-controlling and triplet-sensitizing units was developed, and was found to be effective in accelerating the Norrish-Yang photocyclization of 2-cyanomethyloxyacetophenone. [ABSTRACT FROM AUTHOR]