Genetic studies on premating isolation in Drosophila simulans. II. A D. simulans line highly crossable to males of D. yakuba and D. teissieri

Females of the S1 line of Drosophila simulans, an isofemale line from a natural population at Mishima, Japan, were found to show high crossability to males of D. yakuba and D. teissieri. With D. yakuba males, 24.0-58.5% of the S1 females were inseminated, while the rate was only 0.0-6.3% for the control lines. The high crossability was ascribed to the genes on the X and third chromosomes. With D. teissieri males, 38.0-51.5% of the S1 females were inseminated, while the rate was only 0.0-6.2% for the control lines. The crossability was ascribed to the genes on the third chromosome, and possibly the second chromosome genes acted additively. The crossabilities of hybrid females between the S1 and the control lines were intermediate between the parental lines both to D. yakuba males and to D. teissieri males.     

Modulatory effects of Duguetia furfuracea (A. St. Hil) Benth. and Hook. f. in Drosophila melanogaster somatic and germinative cells

Mutagenic and antimutagenic activities of the medicinal plant Duguetia furfuracea were assessed using SMART/wing and ring-X-loss tests. For the ring-X-loss test, 2- to 3-day-old Drosophila melanogaster ring-X-lineage males and virgin ywsn3 females received D. furfuracea infusion at doses of 0.085, 0.042, or 0.014 g/mL for 24 h. We found that D. furfuracea did not produce any mutagenic effects in D. melanogaster germinative cells. The somatic cells of D. melanogaster were analyzed using the SMART/wing test involving three lineages - mwh, flr3, and ORR - and the same doses of D. furfuracea infusion employed in the ring-X-loss test, as well as 20 mM urethane. The results of both standard (ST) and high bioactivation (HB) crosses showed absence of mutagenic activity of D. furfuracea. In contrast, in both ST and HB crosses, we observed a modulatory effect of D. furfuracea against the genotoxic activity of urethane.     

异戊烯基转移酶基因转化胡卢巴的研究

将含有生长素诱导的小分子RNA启动子与异戊烯基转移酶基因的融合基因 ( pSAUR—ipt)的Ti质粒作为供体DNA ,通过花粉管通道法导入胡卢巴中。D1、D2 代植株经Southern杂交检测 ,有杂交带出现 ,获得了转基因胡卢巴。对转基因胡卢巴D3、D4和D5 代进行了生理生化指标及田间性状分析 ,发现转基因胡卢巴与CK相比有植株略矮、分枝数增多、双角数增多等表型变化 ,D4代叶绿素含量、半乳甘露聚糖含量增加 ,D5 代可溶性蛋白和细胞分裂素含量增加 ,它们都与产量呈正相关性。从而证明了 pSAUR—ipt基因已导入胡卢巴中。     

The polytene chromosomes of Drosophila triauraria and D. quadraria, sibling species of D. auraria.

The polytene chromosomes of Drosophila triauraria and D. quadraria, two of the sibling species of D. auraria, were examined. The polytene chromosomes of all three species exhibit very clear homology. Unlike the stock of D. auraria that we studied, D. triauraria and D. quadraria carry heterozygous paracentric inversions. In both species, 2R and 3R are the arms where these inversions are concentrated. In addition, in D. quadraria, the 3L chromosome arm is very complicated because of heterozygous inversions. The mode of inheritance of these rearrangements was studied. A homozygous strain for all chromosome arms of D. triauraria was isolated, while a homozygous strain was obtained only for the arms X, 2L, 3L, and 4 of D. quadraria. Like D. auraria, both species show a large number of inverted tandem duplications in the paired condition, even in the chromosomes of their hybrids. Small deletions were also detected, one of which, in D. triauraria, is homozygous terminal. Hypotheses are discussed concerning the relationships of the species and the existence of inverted tandem duplications.     

The phylogeny of nine species of the Drosophila obscura group inferred by the banding homologies of chromosomal regions. III. Element D.

The phylogenetic relationships among nine species belonging to the obscura group of the genus Drosophila were deduced, based on similarities of the banding pattern of their polytene chromosomal element D. These similarities were inferred by the comparison of chromosomal photomaps. The phylogenetic reconstruction was the most parsimonious based on seriation by overlapping inversions and on the principle of conservation/disassociation of nearby located segments. The gene sequences of element D for all species studied were relatively easy to recognize in terms of the map of D. obscura, already found to occupy a relative central position in this group. Thus, three clusters of closely related species could be identified: obscura (D. obscura, D. ambigua, and D. tristis), African (D. kitumensis and D. microlabis), and subobscura (D. subobscura, D. madeirensis and D. guanche), with D. subsilvestris standing apart. The results are in agreement with those from the previously studied elements B and E, but element D was found to be much more conclusive concerning the links among the different clusters. Thus, it is inferred that D. guanche occupies an intermediate position between the other two species of its own cluster and all the others. The gene arrangement of D. obscura, directly related to those of the other species, has been identified. In the phylogenetic tree proposed, both the African cluster and D. subsilvestris derive from a hypothetical gene arrangement, intermediate in the pathway between the subobscura and obscura clusters.     

Functional heterogeneity among peritoneal macrophages. II. Enzyme content of macrophage subpopulations.

Rabbit peritoneal exudate (PE) macrophages were separated into subpopulations on discontinuous density gradients of bovine serum albumin. Four such macrophage subpopulations, referred to as bands A, B, C, and D (from lightest to heaviest buoyant density), were examined for differences in enzyme content. With regard to three acid hydrolases—acid phosphatases, β-glucuronidase, and cathepsin D—cells in bands A and B had greater enzyme activity than cells in bands C and D. A similar distribution of activities was observed for acid p-nitrophenylphosphatase. Peroxidase activity was present only in band D. Lysozyme activity was greatest in band D cells and least in band A cells. Only small differences in cytochrome c oxidase activity were observed among the subpopulations. Arginase activity was found to be greater in cells from band A than cells in bands B, C, and D. Macrophage subpopulations derived from PE macrophages placed in tissue culture for 7 days and macrophage subpopulation cells cultured for 2 days showed differences in acid phosphatase content similar to those seen with freshly obtained subpopulations. These results extend previous work demonstrating heterogeneity among PE macrophages.     

Persistence of D.D.T. and Benzene Hexachloride in Soils

Acid and alkaline soils, both alone and mixed with 2 % of D.D.T. or 2 % of benzene hexa-chloride (mixed isomers, containing 10% of the γ-isomer) have been exposed outdoors or subjected to controlled leaching in the laboratory. Residual insecticide has been estimated at intervals by a method involving dehydrohalogenation, and determinations have also been made of chloride content of soil, chloride leached and pH.
Results showed that both D.D.T. and benzene hexachloride were very stable in the soils, about 95 % of the former and 80 % of the latter being recoverable after 18 months. Very little chloride was leached during this period. The residual insecticide exhibited marked toxicity towards woodlice.
Eighteen months after treatment the benzene hexachloride soils prevented root growth of germinating seeds, while germination and early growth were normal in the D.D.T. soils. This harmful effect of the residual benzene hexachloride was still apparent when 1 part of the treated soil was mixed with 99 parts of the control soil (representing a concentration of less than 0–002 % of the γ-isomer).     

D.D.T. Impregnation of Sacks for the Protection of Stored Cereals Against Insect Infestation

Cotton flour sacks, jute flour sacks, jute bran sacks and jute grain sacks have been impregnated with 1 and 5 % by weight of D.D.T. Treated and untreated sacks, each containing 1 cwt. of a mixture of grain (5 parts) and weatings (1 part), were exposed to severe infestation by adults of Calandra granaria, Tribolium castaneum, Ptinus tectus, Oryzaephilus surina-mensis and Ephestia elutella . After storage for 15 weeks at a mean temperature of 21.3 C. and a mean relative humidity of 65 %, the numbers of adult insects in each sack were determined by sieving the contents.
The results with Ephestia elutella were inconclusive. The results with the four species of beetles showed that the eventual degree of infestation of the contents of the sacks was dependent upon the closeness of weave and the D.D.T. content of the sacking material. Impregnation of sacking with 1 % of D.D.T. should afford adequate protection against insect infestation to clean bagged goods stored in stowages which are not heavily infested. Impregnation with 5 % of D.D.T. should offer a very high degree of protection at all times and can almost entirely prevent infestation, if the treated material is of sufficiently close weave to afford some mechanical hindrance to penetration by insects.     

Studies on the Constituents of Aristolochia versicolar S. M. Hwang

Twenty-four constituents were isolated from the root of Aristolochia versicolar S. M. Hwang (collected from Guangxi province, China). Ten of them (two novel sesquiterpene lacrones and eight known compounds) were reported recently. This paper deals with the other eight compounds. From the petroleum ether extraction a sesquiterpene lactone, C15H20O2, mp. 94–95℃ [α]D36 –49˚ (C=1.8, EtOH), confirmed to be isoaristolactone, was obtained from plants for the first time. On the basis of spectral analysis (UV, IR, 1HNMR, 13CNMR, MS) and chemical reactions its structure was determined as B2. From the petroleum enter unsoluble sec- tion 6-methoxyaristolic acid methyl ester (D1), aristolic acid (D3), 6-methoxyaristolic acid (ari- stolinic acid) (D4f), 6-methoxyaristolochic acid methyl ester (D4y), aristolochic acid A(D5), β-sitosterol-D-glucoside (D10) and allantoin (C2) were isolated and identified. Dx, Ds, and Ds show ed antifertility activity in mice.     

Interrelationships in rats of tissue pools of cholecalciferol and 25-hydroxycholecalciferol formed in u.v. light.

Vitamin D-deficient rats were irradiated with u.v. light three times weekly for 30 min for several weeks. D3 (cholecalciferol) and 25(OH)D3 (25-hydroxycholecalciferol) concentrations in skin, plasma, muscle and adipose tissue were measured. In other experiments, isolated skin or the whole animal was irradiated once and the cholecalciferol response monitored. Only a small fraction of the 7-dehydrocholesterol in skin is converted into D3 (less than 2%), and the presence of fur decreases the proportion converted into 20% of that occurring in shaved rat skin. D3 formed in the skin disappears relatively slowly, so that about 90% has gone after 7 days. In normal rats 10 micrograms of D3 formed over 2 h irradiation only caused a small rise in plasma D3 concentration over the following week, indicative of a high rate of clearance from this tissue. Irradiation of vitamin D-deficient rats for a prolonged period raised plasma D3 and 25(OH)D3 concentrations to a constant value. D3, but not 25(OH)D3, could be found in adipose tissue and muscle. Prolonged irradiation of normal rats showed these tissues and plasma could hold very large amounts of D3. Pharmacokinetic analysis of the changes in D3 concentration in rats showed that the disposition kinetics of D3 was explained by a two-compartment model with half-lives of 13.8 and 7.7 days. The volume of distribution of the more-slowly-turning-over compartment was 500 ml, which presumably reflects the large amounts of D3 that can accumulate in adipose tissue. Rat skin can synthesize about 0.85 ng of D3/mJ of u.v. light energy, but it seems that not all this is available to the rat. Adipose-tissue D3 is available for use by the rat, the t1/2 being 12.0 days.     

Genetics of esterases inDrosophila. IX. Characterization of the JH-esterase inD. virilis

The kinetic characteristics of the main isozymes of Drosophila virilis esterase were studied and Km values of esterase-2, -4, and -6 and p-esterase for alpha- and beta-naphthyl acetate were obtained. Juvenile hormone (JH) was shown to inhibit the p-esterase activity when in competition with beta-naphthyl acetate and the general esterase inhibitor, diisopropylphosphofluoridate (DFP), was shown to inhibit all the components of the D. virilis esterase patterns except p-esterase. While studying the changes of p-esterase activity in D. virilis ontogenesis, the increase in p-esterase activity in the wandering larvae, prepupae, and early pupae was found to correlate with a decrease in JH titer at these stages. The decrease in JH level in a temperature-sensitive lethal mutant larvae of D. virilis at high temperatures was shown to correlate with increased p-esterase activity. These results confirm that p-esterase of D. virilis is JH-esterase.     

Rust fungi on Annonaceae II: the genus Dasyspora Berk. & M.A. Curtis

Dasyspora gregaria, the single species of the allegedly monotypic rust genus Dasyspora (Basidiomycota, Pucciniales), was investigated by light microscopy and DNA sequencing (ITS1-5.8S-ITS2 region, partial LSU and SSU of the nuclear rDNA, mt cytochrome oxidase subunit 3). Both methods indicated that D. gregaria is not a single species but can be split in 11 distinct taxa, each of which appear confined to a single Xylopia species (Annonaceae) host. Herein nine of these are described as new. Both the phylogenetic analyses and morphology show that the species are grouped into two main clades designated Dasyspora gregaria and D. winteri. The first comprises D. gregaria, the type species of the genus, which is restricted to X. cayennensis, two new species on X. aromatica, D. segregaria from northern South America and D. echinata from Brazil. The second clade is formed by D. winteri, recombined from Puccinia winteri on X. sericea, and the new species D. amazonica on X. amazonica, D. emarginatae on X. emarginata, D. frutescentis on X. frutescens, D. ferrugineae on X. frutescens var. ferruginea, D. guianensis on X. benthamii, D. mesoamericana on X. frutescens, and D. nitidae on X. nitida. Dasyspora frutescentis and D. mesoamericana were not clearly distinguishable by their morphology and host associations but differed from another in their sequences and geographic distributions. They are considered cryptic species. An identification key and the distributions are given for all recognized species. Along with molecular data we discuss the systematic position of Dasyspora in the Pucciniales.     

Maternal transfer of photoperiodic information in Siberian hamsters. V. Effects of melatonin implants are dependent on photoperiod.

Photoperiodic information is transferred from female Siberian hamsters to their fetuses during gestation. Although maternal melatonin is known to be essential for the transfer of prenatal photoperiodic information, its specific role is not well defined. The duration of the daily melatonin signal, expressed as an elevation of serum melatonin levels in the maternal circulation, has been hypothesized to convey day length information to the fetus. If this hypothesis is valid, it predicts that identical maternal melatonin signals should affect the fetuses identically, regardless of the prenatal photoperiod. To test this hypothesis, adult females received melatonin in beeswax or beeswax alone. They were paired with males and housed in photoperiods of 12L:12D or 16L:8D. On the day of parturition, mother and young were transferred to constant light (LL). Young males were killed on Day 28 of life, and weights of testes were determined. Prenatal treatment with beeswax alone did not affect the nature of the signal transferred from mother to fetus; young gestated in 12L:12D and reared in LL developed small testes, while those gestated in 16L:8D had large testes. On the other hand, the effect of the prenatal melatonin treatment on postnatal testicular development in LL was inversely dependent on the prenatal photoperiod: testicular growth was stimulated in young gestated in 12L:12D, but inhibited in young gestated in 16L:8D. To verify that the melatonin pellets produced equivalent serum melatonin levels in adult females in 12L:12D and 16L:8D, unmated adult females were killed 6-10 wk after receiving melatonin pellets. Serum levels were elevated in both groups throughout the day and night.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fluorescence in situ hybridization mapping of Avena sativa L. cv. SunII and its monosomic lines using cloned repetitive DNA sequences.

Fluorescent in situ hybridization (FISH) employing multiple probes was used with mitotic or meiotic chromosome spreads of Avena sativa L. cv. SunII and its monosomic lines to produce physical chromosome maps. The probes used were Avena strigosa pAs120a (which hybridizes exclusively to A-genome chromosomes), Avena murphyi pAm1 (which hybridizes exclusively to C-genome chromosomes), A. strigosa pAs121 (which hybridizes exclusively to A- and D-genome chromosomes), and the wheat rDNA probes pTa71 and pTa794. Simultaneous and sequential FISH employing two-by-two combinations of these probes allowed the unequivocal identification and genome assignation of all chromosomes. Ten pairs were found carrying intergenomic translocations: (i) between the A and C genomes (chromosome pair 5A); (ii) between the C and D genomes (pairs 1C, 2C, 4C, 10C, and 16C); and (iii) between the D and C genomes (pairs 9D, 11D, 13D, and 14D). The existence of a reciprocal intergenomic translocation (10C-14D) is also proposed. Comparing these results with those of other hexaploids, three intergenomic translocations (10C, 9D, and 14D) were found to be unique to A. sativa cv. SunII, supporting the view that 'SunII' is genetically distinct from other hexaploid Avena species and from cultivars of the A. sativa species. FISH mapping using meiotic and mitotic metaphases facilitated the genomic and chromosomal identification of the aneuploid chromosome in each monosomic line. Of the 18 analyzed, only 11 distinct monosomic lines were actually found, corresponding to 5 lines of the A genome, 2 lines of the C genome, and 4 lines of the D genome. The presence or absence of the 10C-14D interchange was also monitored in these lines.     

Linkage mapping of human chromosome 10 microsatellite polymorphisms.

Ten microsatellite DNA polymorphisms located on human chromosome 10 were regionally mapped using subchromosomal somatic cell hybrids and linkage analysis. The resulting order of the markers from pter-qter was [D10S89, D10S111], D10S107, D10S109, [D10S91, D10S110, D10S108, D10S88, D10S168], and D10S169. Order of the markers within brackets was uncertain, although the order given was most likely. The microsatellites were distributed along the chromosome from the proximal p arm to near qter, with an unlinked gap between D10S168 and D10S169.     

Dehydroepiandrosterone and dehydroepiandrosterone sulfate dynamics in obesity.

Dehydroepiandrosterone (D) and dehydroepiandrosterone sulfate (DS) dynamics were studied in three obese female subjects following a single injection of [4-14-CA1D and [7 alpha-3-H]-DS tracers. Dynamic parameters were calculated simultaneously by both the urinary and blood method of compartmentalization; Estimates for the urinary secretion and production rates of D were found to be high, and those of DS varied within normal range. Calculation of the conversion factors, rho DDS and rho DSD, by the urinary method revealed a noraml extraglandular DS yields D conversion, while that for D yields DS appeared deficient in obese female subjects. Estimates of inner and outer pool distribution volumes were extremely increased for free D; in contrast to this, moderately increased inner and decreased outer pool volumes of DS were observed. The metabolic clearance rates of D were normal or decreased and those for DS were greater than normal. The blood production rates of both B and DS were higher in obese female subjects than those estimated for normal women in our previous study; These observations suggest a considerable uptake of unconjugated D by adipose tissue, an overall poor D yields DS conversion and an accelerated DS metabolism in obese female subjects.     

Individual chromosome assignment and chromosomal collinearity in Gossypium thurberi, G. trilobum and D subgenome of G. barbadense revealed by BAC-FISH

The experiment on individual chromosome assignments and chromosomal diversity was conducted using a multi-probe fluorescence in situ hybridization (FISH) system in D subgenome of tetraploid Gossypium barbadense (D(b)), G. thurberi (D(1)) and G. trilobum (D(8)), which the later two were the possible subgenome donors of tetraploid cottons. The FISH probes contained a set of bacterial artificial chromosome (BAC) clones specific to 13 individual chromosomes from D subgenome of G. hirsutum (D(h)), a D genome centromere-specific BAC clone 150D24, 45S and 5S ribosomal DNA (rDNA) clones, respectively. All tested chromosome orientations were confirmed by the centromere-specific BAC probe. In D(1) and D(8), four 45S rDNA loci were found assigning at the end of the short arm of chromosomes 03, 07, 09 and 11, while one 5S rDNA locus was successfully marked at pericentromeric region of the short arm of chromosome 09. In D(b), three 45S rDNA loci and two 5S rDNA loci were found out. Among them, two 45S rDNA loci were located at the terminal of the short arm of chromosomes D(b)07 and D(b)09, whilst one 5S rDNA locus was found situating near centromeric region of the short arm of chromosome D(b)09. The positions of the BAC clones specific to the 13 individual chromosomes from D(h) were compared between D(1), D(8) and D(b). The result showed the existence of chromosomal collinearity within D(1) and D(8), and as well between them and D(b). The results will serve as a base for understanding chromosome structure of cotton and polyploidy evolution of cotton genome and will provide bio-information for assembling the sequences of finished and the on-going cotton whole genome sequencing projects.     

ICMSF methods studies. VIII. Comparative study for the enumeration of Clostridium perfringens in foods.

Four methods were compared in an international comparative study for the enumeration of Clostridium perfringens: the SFP (Shahidi-Ferguson perfringens) agar (A), TSC (tryptose-sulfite-cycloserin) agar (B), SC (sulfite-cycloserine) agar (C), and neomycin blood agar (D) methods. The confirmed C. perfringens counts were slightly lower for D than for A-C. The percentages of presumptive colonies confirmed as C. perfringens were essentially the same in each method. The relative numbers of nonspecific colonies were the lowest in C, followed by B, D, and A. The methods were also compared for simplicity and for aspects associated with the recognition and selection of presumptive colonies.     

Carbon source utilization by the marine Dendryphiella species D. arenaria and D. salina

Carbon utilization by the marine Dendryphiella species, D. arenaria and D. salina, was investigated to detect differences in utilization and traits associated with their adaptation to the marine habitat. Fifty-four strains were isolated world-wide and tested for the utilization of various carbon sources using BIOLOG phenotype MicroArray (PM) and for the production of extracellular enzymes on solid culture media and on API ZYM assay strips. PM analysis showed that the fastest growth occurred on several monosaccharides and amino acids, 2-keto-d-gluconic acid, succinamide and turanose. Some polyols were poor carbon sources. However, the two species differed in their utilization rates of carbon sources, forming three major clusters: two separate clusters for D. arenaria and D. salina and a third cluster in which strains of the two species formed separate subclades that correlated with geographic origin. Several carbon sources were also found useful in differentiating the two speices. Dendryphiella salina did not utilize xylitol and quinic acid, whereas D. arenaria grew well on these substrates. The latter failed to grow on sorbitol and grew slowly on mannitol, both were good substrates for the former. There were also no qualitative differences between the extracellular enzymes produced, although laccase and peroxidase activities were confined only to some strains. The physiological similarities exhibited by the two species support the close relationship between D. arenaria and D. salina.     

Dynamics of the exotic Daphnia lumholtzii and native macro-zooplankton in a subtropical chain-of-lakes in Florida, U.S.A.

1. Seasonal dynamics of the exotic Daphnia lumholtzii and native macro-zooplankton species were studied for 2 years in six inter-connected lakes in Florida, U.S.A. The lakes ranged widely in pH, colour and trophic status, and were dominated by copepods.
2. All six lakes contained both D. lumholtzii and the native D. ambigua , but the two species did not overlap in time. D. ambigua was dominant in autumn–spring, coinciding with lower water temperature, higher transparency and lower nutrient and chlorophyll a (Chl a ) concentrations than in summer, when D. lumholtzii was dominant.
3. Based on the field observations, temperature optima were 24 °C for D. ambigua and 29 °C for D. lumholtzii , suggesting that temperature plays a role in determining dominance among the daphnids of subtropical Florida lakes.
4.  D. lumholtzii has not displaced native cladocerans but occupies a 'vacant' seasonal niche, unexploited due to the inability of native taxa to tolerate high temperature. Furthermore, D. lumholtzii did not significantly alter algal–zooplankton interactions. There was evidence of top–down control by grazing, but it was primarily attributable to the native taxa.