Mechanisms and consequences of widespread random monoallelic expression

Although random monoallelic expression has been known for decades to affect genes on the X chromosome in female placental mammals, until a few years ago it was thought that there were few autosomal genes that were regulated in this manner. New tools for assaying gene expression genome-wide are now revealing that there are perhaps more genes that are subject to random monoallelic expression on mammalian autosomes than there are on the X chromosome and that these expression properties are achieved by diverse molecular mechanisms. This mode of expression has the potential to have an impact on natural selection and on the evolution of gene families.     

The Influence of the Inoculum Source of Rhizoctonia solani on Development of Black Scurf on Potato

Rhizoctonia solani, the causal agent of stem canker and black scurf on potato, survives as sclerotia on tubers, in soil and in plant residues. The objective of the present study was to evaluate the importance of inoculum source on disease development. Disease‐free minitubers and seed tubers contaminated with low levels of R. solani were planted in fumigated or artificially inoculated growth mixture in greenhouse experiments. Black scurf incidence and severity were significantly higher when the inoculum was present in both seed tubers and soil, compared with either of them separately. The severity of disease symptoms on the subterranean parts of the plant also were significantly higher in plots where both seed tubers and soil were contaminated, compared with plots where the inoculum source was either the seed tubers or the soil. Thus, both major sources of inoculum, seed tubers and soil, are important in disease development. However, when both sources are present, black scurf incidence and severity are increased, leading to economical damage to tuber yield and quality. Additional results from field trials support these findings. Disease incidence and severity on daughter tubers were correlated with levels of contamination in seed tubers and soil. When seed tubers and soil were heavily infested, the levels of black scurf incidence and severity on daughter tubers were very high; when seed tuber and soil infestation were very low, black scurf incidence and severity on progeny were also lower. Disease levels were reduced by in‐furrow fungicide treatment, but were less effective when the initial levels of the fungus on the seed tubers and in the soil were high.     

The structure of the antennae of the Florida Queen butterfly, Danaus gilippus berenice (Cramer)

Interest in the structure of the antennae of the Florida Queen butterfly arises from the finding that a pheromone is active in their courtship. Light and electron microscopic techniques were used to study the sensilla on the antennae and three types of sensilla with perforated walls were identified. The most common of these are short, thin-walled pegs which are distributed over most of the antennal surface. Long, curved, thin-walled pegs occur in patches on the inner medial antennal surface. Multiple coeloconic sensilla are present having up to 50 pegs in one sensillum. On the outer 28 flagellar subsegments there are two such sensilla per subsegment. In addition there are on the antennae long, thick-walled hairs which are mechanoreceptors and probably also contact chemoreceptors. Sunken pegs, the function of which is not known, occur on the antennae. Grooved sensilla were found with the electron microscope but could not be identified with the light microscope. There was no indication of sexual dimorphism in sensilla types or numbers on the antennae.     

湘江中游江段螺类的种类组成及区系分析

报道了湘江中游江段螺类的调查结果,计有螺类31种(其中5种为湖南省新记录),分别隶属于腹足纲6科11属,其中主要是田螺科的种类.对它们的种类组成、区系、种群大小、分布与栖息环境的关系进行了分析,并讨论了城镇污水未经处理直接排放及修河拦坝对螺类生存环境的影响.     

Identification of surface autoantigens which appear during spermatogenesis

Autoantigens that appear during spermatogenesis in the rabbit were identified using immunoadsorbent chromatography and SDS-PAGE. To identify cell-surface proteins, samples of freshly isolated, staged cells were labeled by the lactoperoxidase or Iodo-Gen iodination procedure and run on SDS-PAGE. Autoradiograms of the stained, dried gels were prepared. By correlating the band patterns in the SDS gels of immunocolumn and surface-labeled samples with the band patterns in the autoradiograms, it was possible to show when the autoantigenic proteins appeared on the cell surface. To further support the identification of membrane autoantigens, surface-labeled, staged cell samples were lysed in Triton X-100 and immunoprecipitated with antitestis cell autoantisera. Three types of autoantigens have been identified: (1) late class antigens that are present only on late spermatids and epididymal spermatozoa, but are intracellular in early stages, (2) early class antigens which occur on the surface of pachytene spermatocytes and are present throughout subsequent stages of development, and (3) early class, transient antigens, which appear on spermatogenic cells but are not present on epididymal spermatozoa.     

Differential Behaviour of Mycelial Growth of Several Botrytis cinerea Strains on either Patchoulol- or Globulol-amended Media

Botrydial and dihidrobotrydial are two characteristic metabolites of the phytopathogenic fungus Botrytis cinerea , which are involved in the development of necrotic lesions on grapevine and tobacco. Patchoulol and globulol, two natural products which are analogues to precursors of botrydial and dihidrobotrydial, were tested on 10 B. cinerea strains which were isolated from different hosts and varied in aggressiveness on grapevine leaves. Mycelial growth of all strains was prevented when they were grown on either patchoulol- or globulol-amended malt agar media (200  μ g/ μ l). Each strain displayed a specific response pattern to those products, according to the high variability previously described for this species. Furthermore, strains were different from one another with regard to their level of aggressiveness against leaves detached from sherry grapevine vineyards.     

Intracellular distribution of neutral proteinases and inhibitors in pig leucocytes. Isolation of two inhibitors of neutral proteinases.

Granule and post-granular-supernatant fractions were obtained from pig leucocyte cells by differential centrifugation in 0.34 M sucrose. Granule extract possesses proteinase activity at acid and at neutral pH. Three groups of neutral and a group of acid proteinases were isolated from granule extracts by chromatography on DEAE-cellulose. In the first group are present elastase-like and plasminogen-activator proteinases, that are inhibited by diisopropylphosphorofluoridate, alpha1-antitrypsin, intracellular leucocyte inhibitor and partly with p-aminomethylbenzoic acid and Trasylol. The second group of neutral proteinases is unstable under the conditions of isolation used the third group of neutral proteinases comprises collagenases that are inhibited by ethylenediamine tetraacetic acid disodium salt, alpha1-antitrypsin and leucocyte inhibitor. The acid proteinases are inhibited only with pepstatin, up to 90%. In the post-granular supernatant was found the acid proteinase activity towards hemoglobin and casein, and non-stable neutral proteolytic activity towards bovine serum albumin and serum gamma globulin. In the post-granular supernatant also the inhibitors of neutral proteinases were found. By gel filtration on Sephadex G-100 and ion-exchange chromatography on CM-cellulose two inhibitors of neutral proteinases were isolated. The majority of the inhibitor capacity (about 80%) of post-granular supernatant was eluted together with ovalbumin (Mr 43000) and the remainder with cytochrome c (12300). These inhibitors inhibit the granule neutral proteinases, acting on all substrates used, but do not inhibit granule acid proteinase. Inhibition effects of post-granular-supernatant inhibitors on trypsin and chymotrypsin were obtained only when bovine serum albumin was used as substrate. Inhibitors of post-granular supernatant are stable at pH 6-8, but unstable in the pH rnage 2-5 and are thermolabile.     

转pGH基因猪外源基因染色体定位研究

应用地高辛标记探针对转pGH基因(猪生长激素基因)猪染色体进行原位杂交,经胶体金抗体、银增强放大系统检测外源pGH基因在染色体上的整合位点。研究表明,转基因阳性个体间外源基因整合位点存在差异,但对个体而言,外源基因总是集中分布于某一特定的染色体上。本研究将为探究外源基因整合位点与其表达效率的关系及今后定点整合的研究提供理论指导。     

Effect of counterions on the influence of dodecyltrimethylammonium halides on thermotropic phase behaviour of phosphatidylcholine bilayers

Effects of dodecyltrimethylammonium chloride (DTAC), dodecyltrimethylammonium bromide (DTAB) and dodecyltrimethylammonium iodide (DTAI) on thermotropic phase behaviour of phosphatidylcholine bilayers as well as on 1H NMR spectra were studied. In order to enhance the effect of counterions on water structure two series of experiments were performed. In the first one the surfactants were added to the water phase and in the other one directly to lipid phase (a mixed film was formed). The effects of particular surfactants on the main phase-transition temperature were more pronounced when they were added to the water phase (1st method) instead of the lipid phase (2nd method). Furthermore, in the case of the first method the transitions were found asymmetrical while in the second method nearly symmetrical. It is suggested that surfactant-poor and surfactant-rich domains are formed when surfactants are added to the water phase.     

Construction of a Not I restriction map of the fission yeast Schizosaccharomyces pombe genome.

Pulsed field gel electrophoresis and large DNA technology were used to construct a Not I restriction map of the entire genome of the fission yeast Schizosaccharomyces pombe. There are 14 detectable Not I sites in S. pombe 972h: 9 sites on chromosome I and 5 sites on chromosome II, while no Not I sites were found on chromosome III. The 17 fragments (including intact chromosome III) generated by Not I digestion were resolved by PFG electrophoresis. These fragments ranged in size from 4.5 kb to approximately 3.5 Mb. Various strategies were applied in determining, efficiently, the order of the fragments on the chromosomes. The genomic size measured by adding all the fragments together is about 14 Mb and the sizes of the three chromosomes are I, 5.7 Mb, II, 4.6 to 4.7 Mb, and III, 3.5 Mb. These are generally somewhat smaller than estimated previously.     

An integrated comparative map of the porcine X chromosome

The objectives of this study were to assign both microsatellite and gene-based markers on porcine chromosome X to two radiation hybrid (RH) panels and to develop a more extensive integrated map of SSC-X. Thirty-five microsatellite and 20 gene-based markers were assigned to T43RH, and 16 previously unreported microsatellite and 15 gene-based markers were added to IMpRH map. Of these, 30 microsatellite and 12 gene-based markers were common to both RH maps. Twenty-two gene-based markers were submitted to BLASTN analysis for identification of orthologues of genes on HSA-X. Single nucleotide polymorphisms (SNPs) were detected for 12 gene-based markers, and nine of these were placed on the genetic map. A total of 92 known loci are present on at least one porcine chromosome X map. Thirty-seven loci are present on all three maps; 31 loci are found on only one map. Location of 33 gene-based markers on the comprehensive map translates into an integrated comparative map that supports conservation of gene order between SSC-X and HSA-X. This integrated map will be valuable for selection of candidate genes for porcine quantitative trait loci (QTLs) that map to SSC-X.     

The degree of oligophagy in Locusta migratoria (L.)

• 1 Locusta migratoria in the field feeds mainly on grasses, including cultivated species, but there are numerous reports of feeding on other monocotyledons. Feeding on dicotyledons is reported, but in many cases non-grasses are only accepted in the absence of grasses. Previous laboratory work also indicates that grasses comprise the main food, though other plants are eaten.
• 2 Field observations on nymphal bands in Australia show that the insects select grasses within the habitat; dicotyledons are generally rejected.
• 3 The feeding response to 209 species of plants from fifty-six families was tested. The grasses and some Cyperaceae and Juncaceae were generally fully eaten. Some other monocotyledons, such as palms, were also accepted though only small amounts were eaten; orchids and lilies were rejected. Very few dicotyledons were eaten. The dicotyledons which were eaten after 5h without food were rejected after only 1 h; the grasses were readily accepted after the shorter interval
• 4 The degree of oligophagy depends on the choice of food available and the time for which the insect has been deprived of food and water. Grass is normally eaten if available; in its absence, insects which have been without food for some hours will feed on a wide range of plants, but the amounts eaten are usually small.

     

Selection Practices of Bonga Sheep Reared in Southern Ethiopia

The study was conducted to assess the traits traditionally used to select the Bonga sheep reared in Southern Ethiopia. The breed was included for improvement under the community based breeding program (CBBP) launched in the year 2009. The results are based on the data collected from the project between 2009 till 2012. The findings are based on focus group discussions with the community elders who have been rearing the Bonga sheep for more than 20 years. The present findings are based on information obtained from 50% of the total respondents who were involved in CBBP. The Bonga sheep is a mutton type breed and the ewes are moderately prolific. In the past this breed of sheep were bartered to settle legal disputes and were traded against household commodities.. However, over the years (and also after the intervention of CBBP) the sheep have been selected for their body weight as well as for their distribution in many parts of Ethiopia The respondents selected the lambs at both pre weaning and post weaning stages. Traditionally the traits of rams are selected based on their body length, canon circumference, broad face, enlarged thyroid, while for the ewes, traits prolificacy, skin thickness and pelvic width are determining characters. Fat tail and brown coat color were preferred irrespective of the sexes in trait selection. The ram lambs selected for breeding purpose are locally known as “Dookoo”. These rams are selected based on some predetermined phenotypic traits and are initially selected at preweaning stage and further, again at the post weaning stage. These rams are preferentially cared and are provided with supplementary feed and comfortable housing.     

Ecology of Arcobacter species in chicken rearing and processing

AIMS: To investigate whether Arcobacter spp. colonize the poultry-rearing environment or whether they are contaminants acquired during transportation and/or from the processing plant. METHODS AND RESULTS: Samples were collected on poultry farms and in the processing plant during slaughter and dressing. Two cultural methods of detection were used. Isolates were identified to species level using a multiplex-polymerase chain reaction (m-PCR) method, either on the initial suspensions, or after enrichment, or on pure cultures of isolates. Of the 62 samples examined from poultry farms, arcobacters were found only outside the rearing sheds (in effluent sludge and stagnant water). Thirty-four samples were examined from the processing plant and 26 were positive for arcobacters. All the isolates were Arcobacter butzleri. Arcobacters were not found in any sample by direct plating nor by m-PCR on the initial suspensions, thus it was concluded that numbers were very low. CONCLUSIONS: Arcobacter spp. were not found in samples from the live birds and their immediate environment, but A. butzleri was found in effluent sludge and stagnant water outside the rearing sheds. However, A. butzleri is common in poultry abattoirs, and it appears that poultry carcasses are contaminated during processing. SIGNIFICANCE AND IMPACT OF THE STUDY: Arcobacters are not found inside poultry-rearing sheds, but are contaminants in the processing environment.     

Limitation of point source pesticide pollution: results of bioremediation system

Groundwater and surface water is at risk of contamination from the use of some agricultural pesticides. In many circumstances pesticide contamination of water resources is more likely to result from point sources than from diffuse sources following approved application to crops in the field. Such point sources include areas on farms where pesticides are handled, filled into sprayers or where sprayers are washed down. To overcome this way of contamination different kind of bio-remediation systems are nowadays in development. In Flanders, Belgium two pilot plants of bioremediation systems for the in situ retention and/or degradation of pesticides were installed. Both systems were based on the Phytobac concept, a watertight excavation filled with straw, peat, compost and soil. The channel was made in the bottom from plastic foil. All kinds of spray rests were captured by the phytobacs. This study focuses on what level pesticides leach, bio-degrade or are retained by the filling of the phytobac. The soil-properties of the filling were investigated. Pesticide tracers were added for monitoring to both phytobacs. Soil and water samples were taken during one year. Pesticides are retained at least for one month by the filling of the phytobac. Almost no pesticide leached out. In winter hardly any pesticide degradation was observed in the filling of the phytobac. In summer no detectable pesticides were still left in the phytobacs.     

The effect of genotype on the rate of regeneration of plants in a microspore culture of Triticum aestivum L

The effect of genotype on the productivity of in vitro microspore culture of wheat (Triticum aestivum) was studied. Wheat cultivars and hybrids bred in Kazakhstan and used in the programs on breeding new high-productivity and disease-resistant cultivars and forms of plants were tested. The genotypes that are responsive to androgenesis have been found among the cultivars tested: cultivars Kazakhstanskaya 4, Kazakhstanskaya 5, and hybrids obtained from crosses with the participation of these cultivars (K-6, B-5, and B-10). Such genotypes are recommended to be used as model objects in the studies on androgenesis and plant biotechnology. Based on the use of haploid technology, wheat dihaploid lines were created that are currently tested by breeders.     

山西历山和庞泉沟自然保护区木生真菌（英文）

对山西省历山和庞泉沟自然保护区的木生真菌进行了野外采集和室内鉴定研究,在532号标本中,鉴定多孔菌105种,革菌及齿菌18种。其中齿状真菌棉毛纤刺皮菌Fibrodontia gossypina、钙生棕绒毛菌Tomentella calcicola和孔状真菌白褐叉丝孔菌Dichomitus albidofuscus为我国木生真菌新记录种。根据采集的标本,对3种真菌进行了详细的描述及显微结构绘图,并列出上述123种木生真菌的名称,同时列出了每种的寄主或基质。     

Descriptions of two new species of coccidia (Protozoa: Eimeriidae) and redescriptions of Eimeria ivensae and Eimeria odocoilei from captive white-tailed deer, Odocoileus virginianus

Two new species of Eimeria were observed in the feces of captive white-tailed deer fawns, Odocoileus virginianus, from Alabama. The first new species was easily recognized because of its small size. Sporulated oocysts are spherical, average 10.2 by 10.0 microm, and lack a micropyle and oocyst residuum. Oocysts contain a polar granule and elongate-ellipsoidal sporocysts that measure 6.7 by 3.1 microm. A Stieda body is present on the sporocysts. Oocysts were observed in the feces, and gamonts and oocysts were observed in the jejunum of a month-old fawn from Minnesota that died from enteritis due to this species. Oocysts of this small species were present in 5 of the 6 white-tailed deer fawns examined. Oocysts of a second new species are ellipsoidal and average 29.5 by 24.6 microm. The oocyst encloses an oocyst residuum, polar granule, and elongate-ellipsoidal sporocysts that average 16.0 by 9.0 microm. A Stieda body and substieda body are present on the sporocysts. Oocysts of the second new species were present in 4 of the 6 white-tailed deer fawns examined. Oocysts of E. ivensae are ovoid or flask-like and average 32.0 by 20.8 microm. The oocyst wall is rough, contains a micropyle, and encloses elongate-ellipsoidal sporocysts that average 16.5 by 7.8 microm. A Stieda body is present on the sporocysts. Oocysts of E. ivensae were present in 4 of the 6 white-tailed deer fawns. Oocysts of E. odocoilei are spherical or slightly subspherical and measure 24.7 by 21.5 microm. They enclose ovoid sporocysts that average 12.7 by 8.8 microm. A Stieda and substieda body are present on the sporocyst. Oocysts of E. odocoilei were present in 4 of the 6 white-tailed deer fawns.     

Coordination of flagella on filamentous cells of Escherichia coli.

Video techniques were used to study the coordination of different flagella on single filamentous cells of Escherichia coli. Filamentous, nonseptate cells were produced by introducing a cell division mutation into a strain that was polyhook but otherwise wild type for chemotaxis. Markers for its flagellar motors (ordinary polyhook cells that had been fixed with glutaraldehyde) were attached with antihook antibodies. The markers were driven alternately clockwise and counterclockwise, at angular velocities comparable to those observed when wild-type cells are tethered to glass. The directions of rotation of different markers on the same cell were not correlated; reversals of the flagellar motors occurred asynchronously. The bias of the motors (the fraction of time spent spinning counterclockwise) changed with time. Variations in bias were correlated, provided that the motors were within a few micrometers of one another. Thus, although the directions of rotation of flagellar motors are not controlled by a common intracellular signal, their biases are. This signal appears to have a limited range.     

An investigation of the binding sites of proteins S8, L23 and L24 on the ribosomal RNAs of Escherichia coli by electron microscopy

Summary An electron microscopic method was used to investigate the binding regions of protein S8 on 16S RNA, and proteins L23 and L24 on 23S RNA. Regions of the RNA that were not stabilised by the protein were completely denatured in 80% dimethylsulfoxide. The lengths of these denatured RNA regions were compared with that of the whole denatured RNA.Conclusions are drawn concerning the approximate location of the three proteins and these results are correlated with both RNA structural data and RNA sequence data on the RNA binding regions of the proteins.