Experiments inducing prospective polar body nuclei to participate in embryogenesis of the sawfly Athalia rosae (Hymenoptera)

Summary Mature eggs dissected from ovaries of unmated females of Athalia rosae (Hymenoptera: Tenthredinidae), if placed on a filter-paper soaked with distilled water, are activated and develop to haploid males. Occasionally, however, diploid females develop from these artificially activated eggs. Treatment of mature unfertilized eggs dissected from diploid females with ice-cold temperatures immediately before activation and with a high temperature (36° C) upon and immediately after activation resulted in the production of diploid males, diploid females, triploid females and gynandromorphs at high frequency. The same treatment of mature unfertilized eggs dissected from triploid females resulted in the production of only triploid survivors. These results, together with the results on the segregation of a marker mutation, yellow fatbody (yfb), appear to indicate that meiotic divisions were complete in the treated eggs, and that all four nuclei became potentially capable of participating in development with or without automictic fusion.Studies on the sawfly, Athalia rosae (Insecta, Hymenoptera, Tenthredinidae), part V     

A Comparative Study of the Structures of {alpha}-Glucans from Suspension-Cultured Nonglutinous and Glutinous Rice Cells

-Glucans (average mol wt, 1.3 ? 10⁴) extracted with perchloricacid from 8-day-old suspension-cultured nonglutinous (var. Sasanishiki)and glutinous rice (var. Miyakogane) cells were compared. Theresults of hydrolysis by alpha;-, ß- and iso-amylasesand methylation analysis of the -glucans suggested that theirbasic structures are almost the same. These -glucans are highly-branchedpolysaccharides with an average chain length of about 9–10,with exterior and interior chain lengths of about 6–7and 2–3, respectively. ¹Current address: Laboratory of Food Science, Faculty of Education,Hirosaki University, Hirosaki, Aomori 036, Japan. (Received April 27, 1987; Accepted March 2, 1988)     

Analysis of intergenic spacer regions in the nuclear rDNA of Pharbitis nil.

The nucleotide sequence of a 4.2-kb EcoRI fragment from the intergenic region between the genes for 25S and 18S ribosomal RNA of Pharbitis nil Choisy was determined. The region contained a unique repetitive family of DNA sequences, called the RsaI family, composed of 32-bp units. The 32-bp unit was tandemly repeated in the intergenic region, and four subfamilies of repeating units were clustered as discrete blocks. The RsaI family of repeats was shown to be specific to the genus Pharbitis by Southern blot hybridization.     

Phylogeny of gymnosperms inferred fromrbcL gene sequences

Partial nucleotide sequences of the large subunit of ribulose-1,5-bisphosphate carboxylase (rubisco) gene (1333 base pairs: about 90% of the gene) from several seed plants were determined. Phylogenetic trees based on amino acid sequences were inferred by using the neighbor joining and maximum likelihood methods. The results indicate (1) monophyly of gnetum group (Ephedra, Gnetum, Welwitschia), (2) monophyly of extant gymnosperms containing gnetum group, which contradicts the results of morphological data.     

Mutagenicity and antimutagenicity of air-borne particulates

A methanol extract of air-borne particulates collected in a suburban area of Okayama City showed not only mutagenicity but also antimutagenicity in the Ames test. Thus, when the mutagenicity of this preparation in Salmonella typhimurium TA98 (with metabolic activation) was measured, we observed that the dose response reached a plateau at 27 m3 air equivalent of the particulate, showing approximately equal numbers of revertants in the dose range 27-270 m3 equivalent. This plateau formation was not seen in the dose response of a blue-cotton extract of this preparation: the extract gave a linearly increasing dose response up to 270 m3 equivalent. This finding suggests that some factors that inhibit the mutagenicity were present in this methanol extract and that these inhibitors were not adsorbable to blue cotton, an adsorbent selective for compounds having 3 or more fused rings. From the portion unadsorbed to blue cotton, we isolated the antimutagenic factors and identified them as long-chain fatty acids: palmitic, stearic, oleic and linoleic acids. Analysis of several samples, including those from other parts of Japan, has suggested that these antimutagenic fatty acids are ubiquitous in air-borne particulates.     

Regulated Expression of a Gene-Fusion Product Derived from the Gene for Phytochrome I from Pisum sativum and the uidA Gene from E. coli in Transgenic Petunia hybrida

The 5'-upstream region (2.4 kb) of the gene for phytochromeI from Pisum sativum (phyl) was fused to the uidA gene fromEscherichia coli that encodes ß-glucuronidase (GUS).The resulting PHY-GUS fusion was introduced into Petunia hybridaand was used as a reporter of the expression of the phyI genewhich was recognized by GUS activity. The PHY-GUS fusion wasexpressed at a relatively high level when transgenic plantswere grown in the dark, while leaves and stems of light-grownplants showed background activity. Flowers of light-grown plantswere shown to have significant levels of GUS activity but rootsdid not have such activity. When light-grown transgenic plantswere transferred to the dark, they expressed the activity atlevels that corresponded to those of dark-grown plants. Lighttreatment prior to growth in darkness revealed red/far-red reversibilityof recovery of the activity. Thus, the 2.4-kb fragment fromthe 5' region of the phyI gene carries the information necessaryfor the light-repressible autoregulation. (Received March 30, 1991; Accepted May 20, 1991)     

Ca2+/Diacylglycerol-Activated, Phospholipid-Dependent Protein Kinase in the Hermissenda CNS

In mammalian systems, Ca2+/diacylglycerol-activated phospholipid-dependent protein kinase (C-kinase) appears to play an important role in regulating physiological responses that outlast the transient rise in cytosolic Ca2+. Electrophysiological experiments in neurons of the nudibranch mollusc, Hermissenda crassicornis, have suggested a role for C-kinase in the long-lasting reductions in early and late K+ currents that have been observed following associative learning. Accordingly, we have investigated the catalytic properties of C-kinase in Hermissenda CNS. Following homogenization in Ca2+-free buffer, C-kinase can be separated from Ca2+/calmodulin-dependent protein kinase by centrifugation; C-kinase activity is found in the supernatant whereas essentially all of the Ca2+/calmodulin-dependent protein kinase is found in the membrane fraction. Addition of Ca2+, phosphatidylserine, and diacylglycerol to the cytosol results in phosphorylation of at least eight endogenous proteins. The Hermissenda CNS C-kinase can also phosphorylate lysine-rich histone, a substrate for mammalian C-kinase. The molluscan enzyme exhibits phospholipid specificity in that phosphatidylserine is much more effective than phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, and phosphatidic acid. Addition of diacylglycerol, in the presence of Ca2+ and phosphatidylserine, increases the activity of the C-kinase. The percentage of activation by diacylglycerol is larger at lower Ca2+ concentrations. Enzyme activity is inhibited by trifluoperazine and polymixin B sulfate. These studies indicate that the Hermissenda C-kinase is catalytically similar to mammalian C-kinase.     

Fluorometric determination of gizzerosine, a histamine H2-receptor agonist discovered in feedstuffs, employing high-performance liquid chromatography

Gizzerosine (2-amino-9-(4-imidazolyl)-7-azanonanoic acid) was discovered in fish meal as a causative material of gizzard erosion in chicks. This compound stimulates gastric acid secretion as a histamine H2-receptor agonist and induces gizzard erosion in chicks. A method of fluorometric determination of this compound was developed employing high-performance liquid chromatography. By this method, 0.2 to 5.0 micrograms of gizzerosine in fish meals was quantitated with the recovery of 95-102%. Fish meals, which induced severe gizzard erosion in chicks, contained more than 20 mg/kg of gizzerosine. The present method will be useful in preventing gizzard erosion in chicks, which is a big problem in the poultry industry all over the world.     

Reduction of Aluminum Toxicity by Addition of a Conditioned Medium from Aluminum-Tolerant Cells of Carrot

The toxic effect of aluminum (Al) on the growth of Carrot cells(SO-l) decreased to a greater degree with addition of a mediumconditioned by Al-tolerant carrot cells (TA-l) than with a mediumconditioned by SO-l cells. The toxic effect of Al was reducedgreatly by adding an acidic fraction of the conditioned media,but little or not at all by a neutral or basic fraction. Offour organic acids detected in the acidic fraction, the majorone was citric acid which was present in a much greater amountin the conditioned medium of TA-l cells than in that of SO-lcells. The toxic effect of Al was reduced by adding citric or malicacid instead of the conditioned medium, but not by succinicor fumaric acid. Chelating abilities of the organic acids wereevaluated by shifts in their titration curves, and were foundto be closely correlated with the detoxification effects. Thus,the Al tolerance of TA-l cells may in fact be due to the chelatingeffect of citric acid which is abundantly released into themedium by the Al-tolerant carrot cells. (Received July 9, 1984; Accepted November 22, 1984)