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... The recent emergence of a unique group of North American type 1 porcine reproductive and respiratory syndrome virus (PRRSV) in the United States presents new disease control problems for a swine industry that has already been impacted seriously by North American type 2 PRRSV. In this study, a full-length cDNA infectious clone was generated from a low-virulence North American type 1 PRRSV isolate, ...
... The random collision hypothesis is a mathematical idealization of intestinal tumor formation that can account for the polyclonal origin of tumors without requiring a mechanistic description of clonal interaction. Using data from recent polyclonality studies in mice, we develop a statistical procedure to test the random collision hypothesis. Elements from stochastic geometry and approximations due ...
... Differential display was used to isolate cDNA clones showing differential expression in response to ABA, drought and cold in barley seedling shoots. One drought-regulated cDNA clone (DD12) was further analyzed and found to encode a branched-chain amino acid aminotransferase (HvBCAT-1). A genomic clone was isolated by probing the Morex BAC library with the cDNA clone DD12 and the structure of Hvbca ...
... In 1994, the bacterial parasite Mycoplasma gallisepticum expanded its host range and swept through populations of a novel host -- eastern US populations of the house finch (Carpodacus mexicanus). This epizootic caused a dramatic decline in finch population numbers, has been shown to have caused strong selection on house finch morphology, and presumably caused evolutionary change at the molecular l ...
... Due to the adverse effects of cold temperatures on winter wheat, frost tolerance is an important trait for breeding programs in regions with severe winters. Frost tolerance locus Fr-A ᵐ 2 was recently discovered in diploid wheat (Triticum monococcum L.). This locus was mapped as a QTL on chromosome 5Aᵐ in the same region as a QTL for the level of transcription of the cold-regulated gene COR14b at ...
... The aim of this investigation was to identify and isolate genes involved in acid tolerance from Sinorhizobium sp. strain BL3. It was hypothesized that acid tolerance of strain BL3 could be enhanced by high level expression of certain genes involved in acid tolerance, following insertion of these genes in a multiple copy plasmid. A cosmid clone library of BL3 was introduced into BL3, and the transc ...
... In an effort to increase the density of sequence-based markers for the horse genome we generated 9473 BAC end sequences (BESs) from the CHORI-241 BAC library with an average read length of 677 bp. BLASTN searches with the BESs revealed 4036 meaningful hits (E ≤ 10−5) in the human genome that provide useful markers for the human–horse comparative map. The 4036 BLASTN hits allowed the anchoring of 3 ...
... A mathematical model for the growth and conversion of somatic embryos was developed with the aim of monitoring the large scale production of oil palm microplants. The predicted biomass of somatic embryos obtained and subcultured (B ₙ), together with the number of harvested shoots (Sh ₙ) – two key parameters for production forecasts – have been modeled for seven different shoot harvesting procedure ...
... As a model for analyzing the production of novel fatty acids in oilseeds, we used the genetic and molecular techniques available for Arabidopsis to characterize modifying mutations affecting the accumulation of hydroxy fatty acids in the seeds of Arabidopsis plants that express a transgene for the castor bean fatty acid hydroxylase, FAH12. We developed a high-throughput analytical system and used ...
... In the present work, we report the use of bacterial colonies to optimize macroarray technique. The devised system is significantly cheaper than other methods available to detect large-scale differential gene expression. Recombinant Escherichia coli clones containing plasmid-encoded copies of 4,608 individual expressed sequence tag (ESTs) were robotically spotted onto nylon membranes that were incu ...
... A pathogenesis related protein (AhPR10) is identified from a clone of 6-day old Arachis hypogaea L. (peanut) cDNA library. The clone expressed as a ~20 kDa protein in E. coli. Nucleotide sequence derived amino acid sequence of the coding region shows its homology with PR10 proteins having Betv1 domain and P loop motif. Recombinant AhPR10 has ribonuclease activity, and antifungal activity against t ...
... Several gibberellic acid (GA₃)-induced cDNA fragments encoding putative serine/threonine protein phosphatase (PP) 2A catalytic subunits were obtained by means of differential reverse transcriptase-PCR approach. The full-length clone, named FsPP2A1, isolated from a beechnut cDNA library, exhibited all the features of and homology to members of the PP2A family. By transient expression of FsPP2A1 in ...
... We have recently described a revised scheme for spermatogonial expansion in non-human primates. We proposed that Apale-spermatogonia act as self-renewing progenitors and premeiotic germ cells are organized and divide as small clones. Here, we are revisiting the model described for man and propose a modified scheme for spermatogonial expansion. Our revised model shows high similarity to the scheme ...
... A transcriptional comparison of wild type and a secondary metabolite deficient Trichoderma virens mutant resulted in the identification of six genes similar to those involved in secondary metabolism in other fungi, including four cytochrome P450 genes, one O-methyl transferase and one terpene cylase. Four of the genes (three cytochrome P450s and the cyclase) are located as a cluster. Transcript le ...
... A sunflower BAC library consisting of 147,456 clones with an average size of 118 kb has been constructed and characterized. It represents approximately 5x sunflower haploid genome equivalents. The BAC library has been arranged in pools and superpools of DNA allowing screening with various PCR-based markers. Each of the 32 superpools contains 4,608 clones and corresponds to a 36 matrix pools. Thus, ...
Saccharum; amplified fragment length polymorphism; breeding programs; clones; cluster analysis; genetic markers; genetic similarity; genetic variation; hybrids; phylogeny; random amplified polymorphic DNA technique; restriction fragment length polymorphism; sugarcane; taxonomy
Abstract:
... Amplified fragment length polymorphism (AFLP) markers were evaluated for determining the phylogenetic relationships, and the diversity in the Saccharum complex using 30 clones belonging to S. officinarum, S. robustum, S. spontaneum, S. barberi, S. sinense and the related genus Erianthus. The phenetic tree of the species clones based on AFLP data was consistent with the known taxonomical relationsh ...
... New individuals in clonal populations arise through the recruitment of sexual or clonal offspring. The predominance of one type of regeneration over the other has been correlated with different selective environmental pressures. We compared the reproductive mode (sexual through seeds and vegetative through plantlets or detached cladodes) of Opuntia microdasys from three desert habitats of the Chih ...
... A polyphasic, culture-independent study was conducted to investigate the abundance and population structure of ammonia-oxidizing bacteria (AOB) in canal sediments receiving wastewater discharge. The abundance of AOB ranged from 0.2 to 1.9% and 1.6 to 5.7% of the total bacterial fraction by real-time PCR and immunofluorescence staining, respectively. Clone analysis and restriction endonuclease anal ...
... Microsatellite-based DNA fingerprinting has been increasingly applied to cacao (Theobroma cacao L.) genotype identification. However, the accuracy and reliability of using high throughput microsatellite analysis for cacao clone identification have not yet been rigorously assessed. Despite the use of highly robust fingerprinting protocols, cacao genotype identification has been affected by genotypi ...
... Clonal testing was studied under different environmental patterns and experimental designs through simulation with the criteria of maximizing broad-sense heritability estimates and genetic gain from clonal selection. Several experimental designs were studied together with three patterns of environmental variability. In addition, empirical 95% confidence intervals for heritability estimates were co ...
... Common wheat (Triticum aestivum L., 2n = 6x = 42) is a polyploid species possessing one of the largest genomes among the cultivated crops (1C is approximately 17 000 Mb). The presence of three homoeologous genomes (A, B and D), and the prevalence of repetitive DNA make sequencing the wheat genome a daunting task. We have developed a novel 'chromosome arm-based' strategy for wheat genome sequencing ...
... To overcome the shortcomings of universal 16S rRNA gene primers 8F and 907R when studying the diversity of complex microbial communities, the 3' termini of both primers were replaced with inosine. A comparison of the clone libraries derived using both primer sets showed seven bacterial phyla amplified by the altered primer set (8F-I/907R-I) whereas the original set amplified sequences belonging al ...
proanthocyanidins; developmental stages; plant-insect relations; herbivores; clones; plant age
Abstract:
... Developmental changes in plant structure and function can influence both mammalian and arthropod feeding preferences for many woody plant species. This study documents age-related changes that occur in the leaf chemistry of trembling aspen (Populus tremuloides Michx., Salicaceae) and discusses implications for the herbivore community and ecosystem processes. We collected leaves from replicate rame ...
... We adapted and optimized the use of the Agrobacterium tumefaciens binary PVX expression system (PVX agroinfection) to screen Solanum plants for response to pathogen elicitors and applied the assay to identify a total of 11 clones of Solanum huancabambense and Solanum microdontum, out of 31 species tested, that respond to the elicitins INF1, INF2A and INF2B of Phytophthora infestans. Prior to this ...
... Standardisation of microsatellite allele profiles between laboratories is of fundamental importance to the transferability of genetic fingerprint data and the identification of clonal individuals held at multiple sites. Here we describe two methods of standardisation applied to the microsatellite fingerprinting of 429 Theobroma cacao L. trees representing 345 accessions held in the worlds largest ...
Archaea; DNA libraries; DNA primers; canyons; clones; community structure; electrons; genes; methane; microbial communities; molecular cloning; oxidation; polymerase chain reaction; ribosomal RNA; sediments; sulfates; Gulf of Mexico
Abstract:
... Sediments overlying a brine pool methane seep in the Gulf of Mexico (Green Canyon 205) were analyzed using molecular and geochemical approaches to identify geochemical controls on microbial community composition and stratification. 16S rRNA gene and rRNA clone libraries, as well as mcrA gene clone libraries, showed that the archaeal community consists predominantly of ANME-1b methane oxidizers; no ...
Cowie, Alison; Cheng, Jiujun; Sibley, Christopher D.; Fong, Ying; Zaheer, Rahat; Patten, Cheryl L.; Morton, Richard M.; Golding, G. Brian; Finan, Turlough M.
... As a means of investigating gene function, we developed a robust transcription fusion reporter vector to measure gene expression in bacteria. The vector, pTH1522, was used to construct a random insert library for the Sinorhizobium meliloti genome. pTH1522 replicates in Escherichia coli and can be transferred to, but cannot replicate in, S. meliloti. Homologous recombination of the DNA fragments cl ...
... There are five cultivated species of pepper, of which Capsicum annuum is the most widely cultivated as a vegetable or spice and the main experimental material of most pepper breeding programs. However, the number of simple sequence-repeat (SSR) markers known for C. annuum is limited. To develop SSR markers for Capsicum species, we constructed four SSR-enriched libraries from the genomic DNA of C. ...
... The characterization of natural recessive resistance genes and virus-resistant mutants of Arabidopsis have implicated translation initiation factors of the 4E family [eIF4E and eIF(iso)4E] as susceptibility factors required for virus multiplication and resistance expression. To date, viruses controlled by these genes mainly belong to the family Potyviridae. Melon necrotic spot virus (MNSV) belongs ...
restriction fragment length polymorphism; fluorescence in situ hybridization; rice; DNA libraries; bacterial artificial chromosomes; Oryza sativa; clones; physical chromosome mapping
Abstract:
... The developments of molecular marker-based genetic linkage maps are now routine. Physical maps based on contigs of large insert genomic clones have been established in several plant species. However, integration of genetic, physical, and cytological maps is still a challenge for most plant species. Here we present an integrated map of rice (Oryza sativa L.) chromosome 5, developed by fluorescence ...
... A cDNA library was constructed from late log-phase cultures of the ichthyotoxin-producing haptophyte, Prymnesium parvum. Approximately 6,300 single-pass 5′ nucleotide sequences (out of nearly 8,000 randomly isolated clones) achieved length and quality criteria for incorporation into an expressed sequence tag (EST) database. Collectively, 3,415 unique genes (tentative unigenes [TUGs]) were assemble ...
... Cryptomeria japonica D. Don is one of the most important forest trees in Japan, but more than 10% of the Japanese population is allergic to its pollen. We constructed a cDNA library derived from pollen grains of C. japonica and performed an analysis of expressed sequence tags (ESTs). We obtained partial sequences from 1929 clones, which represented 1365 unique transcripts. Among the unique transcr ...
... Reassortment is one of the major evolutionary mechanisms of the rotavirus genome. Preferential selection (assortment) of the NSP1 gene segment from either of the parental viruses after coinfection of these viruses has been reported as a notable finding in reassortment. To analyze genetic factors which are associated with preferential selection of the rotavirus NSP1 gene segment into progeny viruse ...
... Pseudomonas fluorescens strain PfG32R, a potential biocontrol agent against soilborne pathogens, frequently loses its antifungal activity and ability to produce enzymes. To characterize genetically the instability of these bacterial functions, we analyzed gacS and gacA genes of PfG32R and three spontaneous mutants of PfG32R (NR1, NR9, and ASW6), which had lost their ability to produce proteases an ...
... Five hundred and six EST-derived markers, 313 SSR markers and 26 BAC end-derived or SCAR markers were anchored by PCR on a subset of a Cabernet Sauvignon BAC library representing six genome equivalents pooled in three dimensions. In parallel, the 12,351 EST clusters of the grapevine UniGene set (build #11) from NCBI were used to design 12,125 primers pairs and perform electronic PCR on 67,543 nonr ...
... Full-length cDNAs are very important for genome annotation and functional analysis of genes. The number of full-length cDNAs from maize (Zea mays L.) remains limited. Here we report the construction of a full-length enriched cDNA library from osmotically stressed maize seedlings by using the modified CAP trapper method. From this library, 2073 full-length cDNAs (accession numbers DQ244142- DQ24621 ...
Jun Li; Michelle M Riehle; Yan Zhang; Jiannong Xu; Frederick Oduol; Shawn M Gomez; Karin Eiglmeier; Beatrix M Ueberheide; Jeffrey Shabanowitz; Donald F Hunt; José MC Ribeiro; Kenneth D Vernick
... BACKGROUND: Complete genome annotation is a necessary tool as Anopheles gambiae researchers probe the biology of this potent malaria vector. RESULTS: We reannotate the A. gambiae genome by synthesizing comparative and ab initio sets of predicted coding sequences (CDSs) into a single set using an exon-gene-union algorithm followed by an open-reading-frame-selection algorithm. The reannotation predi ...
... The tprK gene in the syphilis spirochete, Treponema pallidum subsp. pallidum, undergoes antigenic variation in seven variable (V) regions. tprK is highly variable within T. pallidum strains, and a method has been developed to derive clones of T. pallidum that express a single, unique tprK sequence. Rabbits were infected with three different T. pallidum clones or the parent strain from which the cl ...
Saccharum spontaneum; adverse effects; clones; crossing; flowering; flowers; genotype; pollen; solar radiation; subtropics; sugarcane; temperature
Abstract:
... Four hours extra dark treatment in artificially made photoperiodic chamber induced early flowering in flowering clones i.e. S. 55/99, S. 187/91,S. 301/86, S. 116/2K.S. 73/89 after 12to 14th weeks. Maximum and minimum temperature ranged from 31.0 and 21.4°C respectively. Control plants of respective genotypes flowered generally after one month of the treated plants. Flowered genotypes in photoperio ...
... Association between markers and sugarcane diseases were investigated in a collection of 154 sugarcane clones, consisting of important ancestors or parents, and cultivars. 1,068 polymorphic AFLP and 141 SRR markers were scored across all clones. Data on the four most important diseases in the Australian sugarcane industry were obtained; these diseases being pachymetra root rot (Pachymetra chaunorhi ...
... The relative abundance of bacteria in the mucus and crushed tissue of the Mediterranean coral Oculina patagonica was determined by analyses of the 16S rRNA genes of isolated colonies and from a 16S rRNA clone library of extracted DNA. By SYBR gold staining, the numbers of bacteria in mucus and tissue samples were 6.2 x 10⁷ and 8.3 x 10⁸/cm² of coral surface, respectively, 99.8% of which failed to ...
... We surveyed the diversity of soil Archaea across a large scale elevational gradient of ecosystem types, from foothills forest to alpine tundra in the Front Range of the Rocky Mountains. We used a dilution technique to sequence the single most abundant archaeal 16S rDNA sequence in each of the 40 soil cores distributed across the gradient to compare our results to those of typical 16S clone library ...
gas exchange; drought; carbon; seasonal variation; carbon dioxide; hybrids; stomatal conductance; stems; isotopes; dry matter accumulation; clones; water stress; photosynthesis; Populus; forest trees; net assimilation rate; tree growth; water use efficiency; flood irrigation; genetic variation; Spain
Abstract:
... Seasonal changes in carbon isotope discrimination (Δ) and gas exchange traits were assessed in four Populusxeuramericana clones differing in growth potential. Measurements were made during the second year after establishment in the field under two watering regimes, which were defined by the time-span between flood irrigations, hence resulting in different dry-down cycles: high irrigation (conserva ...
... The white petals of chrysanthemum (Chrysanthemum morifolium Ramat.) are believed to contain a factor that inhibits the accumulation of carotenoids. To find this factor, we performed polymerase chain reaction-Select subtraction screening and obtained a clone expressed differentially in white and yellow petals. The deduced amino acid sequence of the protein (designated CmCCD4a) encoded by the clone ...
... We studied the defense reactions of 33-year-old susceptible and resistant clones of Norway spruce (Picea abies (L.) Karst.) to the major root-rot fungus Heterobasidion annosum (Fr.) Bref. and determined if tissue cultures can be used as a model system for studying defense responses of mature trees at the molecular level. Quantitative PCR analysis of genomic DNA obtained from samples taken at diffe ...
... Six clones of monoclonal antibodies (Mabs) to fowl adenovirus (FAV) serotype 1 were produced. All Mabs reacted positively by enzyme-linked immunosorbent assay. Three Mabs recognized the putative 100-kD hexon protein and reacted to serotype 1 specifically by western blot analysis but did not react to other FAV serotypes (2, 3, 4, 5, 6, 7, and 8a). These Mabs will be useful for immunodiagnosis of FA ...
... Nocardioides aromaticivorans IC177 is a gram-positive carbazole degrader. The genes encoding carbazole degradation (car genes) were cloned into a cosmid clone and sequenced partially to reveal 19 open reading frames. The car genes were clustered into the carAaCBaBbAcAd and carDFE gene clusters, encoding the enzymes responsible for the degradation of carbazole to anthranilate and 2-hydroxypenta-2,4 ...