Deorphanization of Dresden G Protein-Coupled Receptor for an Odorant Receptor

Dresden G protein-coupled receptor (D-GPCR) is one of orphan G protein-coupled receptors (GPCR). Here we report the identification of the ligands and the characterization of D-GPCR. We investigated over 5000 compounds to evoke the response mediated by D-GPCR and identified 3-methyl-valeric acid and 4-methyl-valeric acid as agonists using a cAMP assay. It is of interest that they dramatically enhanced the intracellular cAMP accumulation and the CRE-luciferase activity in CHO-K1 cells and HEK293 cells expressing the chimeric protein of D-GPCR with a rhodopsin-tag at its N-terminus. Our results established new characteristics of D-GPCR as an olfactory receptor. First, agonists of D-GPCR belong to odorants. Second, D-GPCR mRNA is expressed in the olfactory bulb. In addition, D-GPCR was reported to have similar sequences and its genome locus nearby other olfactory receptors. These results suggest D-GPCR is an olfactory receptor.     

Microsatellite loci for the weaver ant Oecophylla smaragdina

We developed 13 microsatellite loci in Oecophylla smaragdina from random amplified polymorphic DNA (RAPD) fragments. These loci showed two to 14 alleles in O. smaragdina with expected heterozygosity of each locus from 0.10 to 0.89, and six were also polymorphic in the related species, O. longinoda. The results suggested that the loci will be useful to analyse the genetic structure of Oecophylla species at both the colony and population levels.     

The role of olfactory cues in the sequential radiation of a gall‐boring beetle,Mordellistena convicta

1. Herbivorous insects often have close associations with specific host plants, and their preferences for mating and ovipositing on a specific host‐plant species can reproductively isolate populations, facilitating ecological speciation. Volatile emissions from host plants can play a major role in assisting herbivores to locate their natal host plants and thus facilitate assortative mating and host‐specific oviposition. 2. The present study investigated the role of host‐plant volatiles in host fidelity and oviposition preference of the gall‐boring, inquiline beetle, Mordellistena convicta LeConte (Coleoptera: Mordellidae), using Y‐tube olfactometers. Previous studies suggest that the gall‐boring beetle is undergoing sequential host‐associated divergence by utilising the resources that are created by the diverging populations of the gall fly, Eurosta solidaginis Fitch (Diptera: Tephritidae), which induces galls on the stems of goldenrods including Solidago altissima L. (Asteraceae) and Solidago gigantea Ait. 3. Our results show that M. convicta adults are attracted to galls on their natal host plant, avoid the alternate host galls, and do not respond to volatile emissions from their host‐plant stems. 4. These findings suggest that the gall‐boring beetles can orient to the volatile chemicals from host galls, and that beetles can use them to identify suitable sites for mating and/or oviposition. Host‐associated mating and oviposition likely play a role in the sequential radiation of the gall‐boring beetle.     

Conservation of electron transport and energy transfer reactions of spinach chloroplasts in glycero

When spinach chloroplasts were suspended in 50% glycerol inthe presence of 5 mM sodium chloride, then stored at –20°Cactivity of the Hill reaction was retained for several monthswith a small loss. Under these conditions photophosphorylationactivity was reduced by half during the month of storage. (Received February 2, 1971; )     

Red and far-red reversible photoreactions on seed germination of Cucumis sativa

The effects of red and far-red light in seed germination ofCucumis sativa differs markedly with the degree of seed ripeningand the variety of seed; reciprocal hybrids are clearly maternal. (Received December 26, 1968; )     

A system for imaging transverse distribution of scattered light and chlorophyll fluorescence in intact rice leaves

In order to examine the transverse distribution of scattered light and chlorophyll fluorescence in intact rice leaves, a micro-fluorescence imaging system was devised using a microscope, a CCD camera with an image intensifier, an Ar and a He-Ne laser light source, an image processor, and a microcomputer. A laser light was projected vertically on to the surface of a rice leaf segment at a cut-edge, and scattered light and induced fluorescence were observed at the cut-section from a 90° angle to the axis of the laser beam. The intensity of scattered light showed a maximum at several micrometres depth from the leaf surface and a steep gradient afterwards. Fluorescence reached a maximum crossing with the decline curve of the scattered light. The maximum of fluorescence measured at 741 nm was observed at a greater depth from the leaf surface than that at 687 nm, suggesting that part of the fluorescence of the longer wavelength was emitted due to absorption of fluorescence of the shorter wavelength. Profiles of the scattered light and the chlorophyll fluorescence depended on leaf anatomy.     

Three Groups of Teratocarcinoma Antigens Co-Expressed in the Visceral Endoderm are Located in Mutually Exclusive Sites in the Adult Kidney

Monoclonal rat antibodies were prepared against glycoproteins isolated from murine teratocarcinoma OTT6050 by affinity chromatography on Ricinus communis agglutinin (RCA). These antibodies defined three distinct groups of antigens (OR antigens) commonly expressed in teratocarcinoma cells and in restricted sites of the kidney. OR 17 antigen was a new glycoprotein antigen and the biochemical properties were different from any membrane glycoprotiens or matrix glycoproteins so far described in teratocarcinoma cells. In the kidney, the antigen was found in the glomerular basement membrane, and to lesser extent in the endothelium of the glomerulus and blood vessels. On the other hand, OR 8 antigen corresponded to "brushin" defined by conventional antibodies, while OR 4 and 19 antigens were carbohydrate antigens resembling "TC antigen". OR 8 antigen was detected in the tubular brush border and the epithelium of Bowman's capsule. OR 4 antigen was present in the collecting tubules and the thin loop of Henle. Although OR 19 antigen showed distribution similar to OR 4 antigen, there were genetic differences in the expression of the former antigen. All of the antigens were present in early postimplantation embryos of the mouse, notably in the visceral endoderm. These antigens are interesting subjects to study the mechanism of differentiation-dependent control of gene expression, since antigenic distribution is specialized as the result of differentiation.     

Effects of photoperiod and temperature on the rhythm and free‐running of adult eclosion in the Indian meal moth Plodia interpunctella

The rhythm of adult eclosion in the Indian meal moth Plodia interpunctella Hübner (Lepidoptera: Pyralidae) is investigated under various photoperiods and temperatures aiming to determine the nature of the temperature compensation and the free‐running period. Insects that are committed to a nondiapause larval development show diel rhythms of adult eclosion at 30, 25 and 20 °C. At 30 °C, the eclosion peak (i.e. the mean time of eclosion) occurs approximately 20 h after lights off under an LD 4 : 20 h photocycle, and at approximately 15 h under an LD 20 : 4 h photocycle. At 25 °C, the peak of eclosion occurs approximately 19 h after lights off under an LD 2 : 20 h photocycle and at approximately 16 h under an LD 20 : 4 h photocycle. At 20 °C, the eclosion peak is significantly advanced under long days of >12 h (i.e. approximately 20 h after lights off under an LD 4 : 20 h photocycle and approximately 9 h under an LD 20 : 4 h photocycle), indicating an effect of both lights‐off and lights‐on signals on the timing of the adult eclosion. To determine the involvement of a self‐sustained oscillator, the rhythm of adult eclosion is examined under darkness at different temperatures (30 to 21 °C). The mean free‐running periods are 22.4, 22.8, 22.0 and 22.5 h at 30, 24, 23 and 22 °C, respectively, indicating that the eclosion rhythm is temperature‐compensated. However, this rhythm does not free‐run under constant darkness at 21 °C. Because a clear diel rhythm is observed under 24‐h photocycles at 20 °C, the oscillator might be damped out within 24 h at the lower temperature.     

Purification and properties of cytochrome c and two peroxidases from spinach leaves

1. A simultaneous purification procedure of cytochrome c, peroxidases,ferredoxin, ferredoxin-NADP reductase and sulfite reductasefrom spinach leaves is described. Cytochrome c, ferredoxin andferredoxin-NADP reductase were prepared in crystalline states.The two peroxidases were obtained in homogeneous states as evidencedby their electrophoretic patterns on acrylamide gel and sedimentationanalysis. 2. Crystalline cytochrome c showed a molecular weight of 13,800and an E₀' of 270 mv at pH 7.0. In addition to these properties,its spectral pattern also indicated that this cytochrome c wasderived from mitochondria. 3. Two peroxidases were isolated in high spin forms after treatmentwith HgCl₂. They had a-peaks at 556 mµ in their reducedforms. Although both peroxidases showed small differences inchromatographic behavior on a carboxymethyl cellulose column,' they had similar spectral properties, dissociation constantsof peroxidase-cyanide complex and rate constants for peroxidasereactions. (Received December 24, 1970; )