Complete Copy Research Articles

The level of ascorbate peroxidase is enhanced in benznidazole-resistant populations of Trypanosoma cruzi and its expression is modulated by stress generated by hydrogen peroxide

Ascorbate peroxidases (APX) are class I heme-containing enzymes that convert hydrogen peroxide into water molecules. The gene encoding APX has been characterized in 11 strains of Trypanosoma cruzi that are sensitive or resistant to benznidazole (BZ). Bioinformatic analysis revealed the presence of two complete copies of the T. cruzi APX (TcAPX) gene in the genome of the parasite, while karyotype analysis showed that the gene was present in the 2.000-kb chromosome of all of the strains analyzed. The sequence of TcAPX exhibited greater levels of similarity to those of orthologous enzymes from Leishmania spp than to APXs from the higher plant Arabidopsis thaliana. Northern blot and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analyses revealed no significant differences in TcAPX mRNA levels between the T. cruzi strains analyzed. On the other hand, Western blots showed that the expression levels of TcAPX protein were, respectively, two and three-fold higher in T. cruzi populations with in vitro induced (17 LER) and in vivo selected (BZR) resistance to BZ, in comparison with their corresponding susceptible counterparts. Moreover, the two BZ-resistant populations exhibited higher tolerances to exogenous hydrogen peroxide than their susceptible counterparts and showed TcAPX levels that increased in a dose-dependent manner following exposure to 100 and 200 µM hydrogen peroxide.

Intellectual Property and Patent Abstracts

Provides summary abstracts from US patents that should be of interest to the readers of this publication. These patent abstracts, from recently issued patents, are intended to provide the minimum information necessary for readers to determine if they are interested in examining the patent in more detail. Complete copies of patents are available for a small fee by writing: US Patent and Trademark Office, Washington, DC, USA.

An investigation on physicians’ acceptance of hospital information systems: A case study

PurposeInformation technology is used to support a wide range of highly specified healthcare tasks and services. There is, therefore, a need to understand the factors affecting the acceptance of this technology by healthcare professionals. Physicians are key providers of healthcare services and are among the principal users of hospital information systems. Their acceptance of hospital information systems is hence of great significance when evaluating the success of those systems. MethodThe survey methodology was employed to targeted physicians in the selected case hospital for investigating factors affecting physicians’ acceptance of hospital information systems. A total of 202 questionnaires were sent out, with 124 completed copies returned, indicating a valid response rate of 61.4%. We used structural equation modeling to analyze the data. ResultsThe results indicated that top management support (γ=0.431, p<0.001) had a significant impact on perceived usefulness. Project team competency (γ=0.381, p<0.001) and system quality (γ=0.369, p<0.001) had a significant impact on physicians’ perceived ease of use of hospital information systems. Physicians’ perceptions of the usefulness (β=0.132, p<0.05, R2=0.296) and ease of use (β=0.952, p<0.001, R2=0.784) of hospital information systems had a significant impact on the acceptance of the systems, accounting for 81.4% of total explained variance. ConclusionsThrough the understanding of the identified critical factors affecting physicians’ HIS acceptance, the planners and managers should ensure that hospital information systems to be introduced into a hospital are useful and ease to use. Effort should be focuses on providing sufficient top management support, selecting qualified project team members, and delivering higher system quality in addressing physicians’ clinical needs. Thus, our research results can help planners and managers understand key considerations affecting HIS development and use, and may be used as a reference for system design, development and implementation.

Git

Git is a distributed revision control system available on all mainstream development platforms through a free software license. An important difference of git over its older ancestors is that it elevates the software's revisions to first-class citizens. Developers care deeply about software revisions, and git supports this by giving each developer a complete private copy of the software repository and numerous ways to manage revisions within its context. The ability to associate a local repository with numerous remote ones allows developers and their managers to build a variety of interesting distributed workflows, most of which are impossible to run on a traditional centralized version control system. The local repository also makes git responsive, easy to setup, and able to operate without Internet connectivity. GitHub is a git repository hosting provider that simplifies many repository management tasks through a Web-based user interface while also promoting cooperation in open source projects.

Tkt1, located on a novel pathogenicity island, is prevalent in avian and human extraintestinal pathogenic Escherichia coli

BackgroundExtraintestinal pathogenic Escherichia coli are important pathogens of human and animal hosts. Some human and avian extraintestinal pathogenic E. coli are indistinguishable on the basis of diseases caused, multilocus sequence and phylogenetic typing, carriage of large virulence plasmids and traits known to be associated with extraintestinal pathogenic E. coli virulence.ResultsThe gene tkt1 identified by a previous signature-tagged transposon mutagenesis study, was found on a 16-kb genomic island of avian pathogenic Escherichia coli (APEC) O1, the first pathogenic Escherichia coli strain whose genome has been completely sequenced. tkt1 was present in 39.6% (38/96) of pathogenic Escherichia coli strains, while only 6.25% (3/48) of E. coli from the feces of apparently healthy chickens was positive. Further, tkt1 was predominantly present in extraintestinal pathogenic E. coli belonging to the B2 phylogenetic group, as compared to extraintestinal pathogenic E. coli of other phylogenetic groups. The tkt1-containing genomic island is inserted between the metE and ysgA genes of the E. coli K12 genome. Among different extraintestinal pathogenic E. coli of the B2 phylogenetic group, 61.7% of pathogenic Escherichia coli, 80.6% of human uropathogenic E.coli and 94.1% of human neonatal meningitis-causing E. coli, respectively, harbor a complete copy of this island; whereas, only a few avian fecal E. coli strains contained the complete island. Functional analysis showed that Tkt1 confers very little transketolase activity but is involved in peptide nitrogen metabolism.ConclusionThese results suggest tkt1 and its corresponding genomic island are frequently associated with avian and human ExPEC and are involved in bipeptide metabolism.

Sensitive and Specific Target Sequences Selected from Retrotransposons of Schistosoma japonicum for the Diagnosis of Schistosomiasis

Background Schistosomiasis japonica is a serious debilitating and sometimes fatal disease. Accurate diagnostic tests play a key role in patient management and control of the disease. However, currently available diagnostic methods are not ideal, and the detection of the parasite DNA in blood samples has turned out to be one of the most promising tools for the diagnosis of schistosomiasis. In our previous investigations, a 230-bp sequence from the highly repetitive retrotransposon SjR2 was identified and it showed high sensitivity and specificity for detecting Schistosoma japonicum DNA in the sera of rabbit model and patients. Recently, 29 retrotransposons were found in S. japonicum genome by our group. The present study highlighted the key factors for selecting a new perspective sensitive target DNA sequence for the diagnosis of schistosomiasis, which can serve as example for other parasitic pathogens.Methodology/Principal FindingsIn this study, we demonstrated that the key factors based on the bioinformatic analysis for selecting target sequence are the higher genome proportion, repetitive complete copies and partial copies, and active ESTs than the others in the chromosome genome. New primers based on 25 novel retrotransposons and SjR2 were designed and their sensitivity and specificity for detecting S. japonicum DNA were compared. The results showed that a new 303-bp sequence from non-long terminal repeat (LTR) retrotransposon (SjCHGCS19) had high sensitivity and specificity. The 303-bp target sequence was amplified from the sera of rabbit model at 3 d post-infection by nested-PCR and it became negative at 17 weeks post-treatment. Furthermore, the percentage sensitivity of the nested-PCR was 97.67% in 43 serum samples of S. japonicum-infected patients.Conclusions/SignificanceOur findings highlighted the key factors based on the bioinformatic analysis for selecting target sequence from S. japonicum genome, which provide basis for establishing powerful molecular diagnostic techniques that can be used for monitoring early infection and therapy efficacy to support schistosomiasis control programs.

Intellectual Property and Patent Abstracts

Provides summary abstracts from US patents that should be of interest to the readers of this publication. These patent abstracts, from recently issued patents, are intended to provide the minimum information necessary for readers to determine if they are interested in examining the patent in more detail. Complete copies of patents are available for a small fee by writing: US Patent and Trademark Office, Washington, DC, USA.

The Chatsworth Uranographia Britannica

In November 1997, two colleagues at Manchester Astronomical Society, Mike Oates and Tony Cross, and I identified, with the help of Peter Hingley, an old star atlas that had been in our library for over 50 years as an Atlas Celeste: an original, bound set of charts from John Bevis’s unpublished atlas Uranographia, ca. 1750. It was the 16th copy known (see Ashworth 1981) and started a quest to learn more about this rare atlas (Kilburn 2007). In about 1745, the London doctor and amateur astronomer Dr John Bevis FRS proposed to compile a modern British star atlas, Uranographia Britannica. He enlisted the help of John Neale, an instrument maker or toy maker of Leadenhall Street, who sought to finance the project with advance subscriptions from those wealthy enough. A copy of the 1746 list of subscribers is held at Glasgow University Library (Sp. Coll. f465). Uranographia was based on Flamsteed’s star positions and Halley’s observations of the southern hemisphere, together with additional stars from Bevis’s own transit observations between 1738 and 1739. In 1750, as Bevis’s atlas was in the process of being printed, disaster struck. Neale was declared bankrupt, the copper plates were sequestered by the London Courts of Chancery and the project was abruptly terminated. It was not until 1785, long after the deaths of Neale and Bevis, that Bevis’s library was auctioned by the widow of his executor, James Horsfall FRS. According to the auction catalogue, which survives in the Whipple Museum, Cambridge, three near-complete atlases were sold, together with an unknown number of pre-printed star charts. These surplus star charts were compiled into an unknown number of atlases and sold cheap, in 1786, as Atlas Celeste. A typical Atlas Celeste comprises: an elaborate frontispiece showing the Muse, Urania, offering a star atlas to a seated man, Frederick, Prince of Wales, with Greenwich Observatory in the background; and 51 star charts, Tab I to LI, each carrying a dedication to institutions or individuals who subscribed to the project. A few atlases have a simple index thought to have been printed in 1786, together with an exceedingly rare title sheet advertising it as Atlas Celeste. Manchester’s Atlas Celeste is considered to be the most complete and original. Of the three, near-complete Uranographia, one was bought at the Sotheby & Wilkinson sale, London, on 21 January 1856 by the American Philosophical Society, Philadelphia. It was formerly owned by Sir George Shuckburgh-Evelyn (1751–1804). This is the atlas on which Ashworth based his 1981 seminal description. Another less complete copy, also identified by Ashworth, is at St John’s Library, Cambridge. The third went unidentified, until November 2011.

Epigenetics for ecotoxicologists

Do genes define your destiny? The field of epigeneticsexamines how genes and the environment interact to formthe basis of heredity and comes up with some surprisingfindings. We often think of deoxyribonucleic acid (DNA) asthe sole physical basis for heredity, the genetic code thatdetermines everything from eye and hair color to specificpersonality traits. The growing field of epigenetics suggeststhat this traditional paradigm is an oversimplification. Epi-genetics is the study of factors that are heritable, but whichoccur by mechanisms other than changes in the DNA codeitself. C.H. Waddington first used the term epigenetics in theearly 1940s to describe ‘‘the interactions of genes with theirenvironment, which bring the phenotype into being.’’ Epi-genetic marks are susceptible to environmental influences—both chemical and nonchemical—and can be inherited inways that may seem counterintuitive (see sidebar, ExpandingIdeas About Biological Inheritance). Effects of early lifeexperiences, such as parental care or nutrition, can showup later in life and even be passed on to future generations.This emerging area of research has interesting and importantimplications for the field of ecotoxicology—from basicscience to international policy.In classic genetics, genetic material is in the form of DNAand encodes all of the information necessary for life. Thisinformation is copied faithfully and passed down as cellsdivide. Every cell contains a complete copy of the DNAcode, but the pattern of gene expression—that is, whichgenes are turned ‘‘on’’ (expressed) or ‘‘off’’ (nonex-pressed)—determines the cell type and function. A skin cellon your arm contains the same DNA code as a nerve cell inyour brain, but their extreme differences in structure andfunction are due to the particular set of genes that each isexpressing. Epigenetics refers to an annotation in the form ofchemical marks on top of the DNA code; the prefix ‘‘epi’’comesfromaGreekwordmeaning‘‘over’’or‘‘above.’’Thesechemical marks, which are discussed in detail below, affectwhich genes are expressed and at what levels. Epigeneticmarks are highly influenced by the environment and can beinherited along with the genetic code as cells divide mitoti-cally, and in some cases meiotically, from one generation tothe next.Epigenetics is receiving significant attention in the field ofbiomedicine. A PubMed search for ‘‘epigenetic’’ revealedthat more than 1,300 review articles have been written on thetopic, of which more than 50% were published in the lastthree years alone. Epigenetics provides a mechanism for theBarker hypothesis, which postulates that nutrition and otherenvironmentalfactorsearlyindevelopmentcanaltersuscept-ibility to chronic diseases in adulthood. A classic exampleof this is that individuals who were conceived during theDutchWinterHunger(1944–1945)havepersistentepigeneticalterations on a characteristic gestational marker, the IGF2gene, as adults. Furthermore, individuals who experiencedthe Dutch Winter Hunger have higher rates of metabolicdisorders and cardiovascular disease, the epigenetic mecha-nisms of which are the focus of ongoing studies. Nutritionaldeprivation may also have an impact on human longevity;indeed, lifespanisnegativelycorrelated withfoodabundance

Molecular and phenotypic characterization of strains nodulating Anthyllis vulneraria in mine tailings, and proposal of Aminobacter anthyllidis sp. nov., the first definition of Aminobacter as legume-nodulating bacteria

Bacterial strains from Zn–Pb mine tailings were isolated by trapping with Anthyllis vulneraria, a legume-host suitable for mine substratum phytostabilisation. Sequence analysis of the 16S rRNA gene and three housekeeping genes (atpD, dnaK and recA) showed that they were related to those of the genus Aminobacter. DNA–DNA relatedness of representative isolates supported the placement of novel strains in Aminobacter as a new species. Phenotypic data emphasize their differentiation from the other related species of Aminobacter and Mesorhizobium. Aminobacter isolates exhibited nodA sequences tightly related with M. loti as the closest nodA relative. By contrast, their nodA sequences were highly divergent from those of M. metallidurans, another species associated with A. vulneraria that carries two complete copies of nodA. Therefore, the novel bacterial strains efficient on A. vulneraria represented the first occurrence of legume symbionts in the genus Aminobacter. They represent a new species for which the name Aminobacter anthyllidis sp. nov. is proposed (type strain STM4645T=LMG26462T=CFBP7437T).

Friend Lens: novel web content sharing through strategic manipulation of cached html

Current methods of content sharing include blogs, social networking sites, and social bookmarking sites. This article details the construction and novel features of Friend Lens, a web application that allows users to both author original content and to extract complete copies of external sites using PHP, making it a hybrid blog and social booking site. Friend Lens implements a method of collaboration with the ability to highlight posts and to make a composite of multiple highlights across many users. Composite highlights use a colour scale to emphasise the content that received the most highlights. Unlike popular social bookmarking sites like Clipmarks or Diigo, all of Friend Lens' functionality works with the need to install a browser plug-in. To evaluate Friend Lens, human subjects rated Facebook, Clipmarks, and Friend Lens in three general categories: community, posting content, and practicality of use. The results are reported in this article.

LTR retrotransposons in fungi.

Transposable elements with long terminal direct repeats (LTR TEs) are one of the best studied groups of mobile elements. They are ubiquitous elements present in almost all eukaryotic genomes. Their number and state of conservation can be a highlight of genome dynamics. We searched all published fungal genomes for LTR-containing retrotransposons, including both complete, functional elements and remnant copies. We identified a total of over 66,000 elements, all of which belong to the Ty1/Copia or Ty3/Gypsy superfamilies. Most of the detected Gypsy elements represent Chromoviridae, i.e. they carry a chromodomain in the pol ORF. We analyzed our data from a genome-ecology perspective, looking at the abundance of various types of LTR TEs in individual genomes and at the highest-copy element from each genome. The TE content is very variable among the analyzed genomes. Some genomes are very scarce in LTR TEs (<50 elements), others demonstrate huge expansions (>8000 elements). The data shows that transposon expansions in fungi usually involve an increase both in the copy number of individual elements and in the number of element types. The majority of the highest-copy TEs from all genomes are Ty3/Gypsy transposons. Phylogenetic analysis of these elements suggests that TE expansions have appeared independently of each other, in distant genomes and at different taxonomical levels. We also analyzed the evolutionary relationships between protein domains encoded by the transposon pol ORF and we found that the protease is the fastest evolving domain whereas reverse transcriptase and RNase H evolve much slower and in correlation with each other.

Current Perspective of HCV NS5B Inhibitors: A Review

Hepatitis C virus (HCV) infection has emerged as one of the most significant disease to affect humans. Despite its large medical and economical impact, there are no vaccines or efficient therapies without major side effects. The HCV non-structural protein 5B (NS5B) is the RNA-dependent RNA polymerase responsible for the complete copy of the RNA viral genome and is a target of choice for the development of anti-HCV drugs. Although many small molecules have been identified as allosteric inhibitors of NS5B, very few are active in clinical applications. Developments in the field have prompted us to review the research work on HCV NS5B polymerase inhibitors, especially their structure activity relationships and molecular modeling studies. This review will focus on the journey of drug discovery of HCV NS5B inhibitors covering both nucleoside and non-nucleosides.

Spider: A System for Finding Illegal 3D Video Copies

Three-dimensional (3D) videos are getting quite popular, and equipment for recording and processing them are becoming affordable. Creating 3D videos is expensive. Thus, protecting 3D videos against illegal copying is an important problem. We present a novel system for finding 3D video copies. Our system also identifies the location of the copied part in the reference video. The system can be used, for example, by video content owners, video hosting sites, and third-party companies to find illegally copied 3D videos. To the best of our knowledge, this is the first complete 3D video copy detection system in the literature. Detecting 3D video copies is a challenging problem. First, comparing numerous numbers of frames from potential copies against reference videos is computationally intensive. Second, many modifications occur on copied videos; some of them are intentional to avoid detection and others are side effects of the copying process. For example, a copied video can be scaled, rotated, cropped, transcoded to a lower bit rate, or embedded into another video. The contrast, brightness, and colors of a video can also be manipulated. Furthermore, 3D videos come in various encoding formats, including stereo, multiview, video plus depth, and multiview plus depth. Changing the format is possible during copying, which complicates the detection process. Finally, new views can be synthesized from existing ones. These views display the scene from different angles, and thus reveal different information than in original views. For example, an object occluded in one view could appear in another. We implemented the proposed system and evaluated its performance using many 3D videos. We created a large set of query videos with 284 videos to represent all practical scenarios. Our results show that the proposed system achieves high precision and recall values in all scenarios. Specifically, our system results in 100% precision and recall when copied videos are unmodified parts of original videos, and it produces more than 90% precision and recall when copied videos are subjected to various transformations. Even in extreme cases where each video is subjected to five different transformations, our system yields more than 75% precision and recall.

Double-Strand Break Repair and Holliday Junction Processing Are Required for Chromosome Processing in Stationary-Phase Escherichia coli Cells

As nutrients are depleted and cell division ceases in batch cultures of bacteria, active processes are required to ensure that each cell has a complete copy of its genome. How chromosome number is manipulated and maintained in nondividing bacterial cells is not fully understood. Using flow cytometric analysis of cells from different growth phases, we show that the Holliday junction–processing enzymes RuvABC and RecG, as well as RecBCD, the enzyme complex that initiates DNA double-strand break repair, are required to establish the normal distribution of fluorescent peaks, which is commonly accepted to reflect the distribution of chromosome numbers. Our results reveal that these proteins are required for the proper processing of chromosomes in stationary phase.

Propagation of histone marks and epigenetic memory during normal and interrupted DNA replication.

Although all nucleated cells within a multicellular organism contain a complete copy of the genome, cell identity relies on the expression of a specific subset of genes. Therefore, when cells divide they must not only copy their genome to their daughters, but also ensure that the pattern of gene expression present before division is restored. While the carrier of this epigenetic memory has been a topic of much research and debate, post-translational modifications of histone proteins have emerged in the vanguard of candidates. In this paper we examine the mechanisms by which histone post-translational modifications are propagated through DNA replication and cell division, and we critically examine the evidence that they can also act as vectors of epigenetic memory. Finally, we consider ways in which epigenetic memory might be disrupted by interfering with the mechanisms of DNA replication.

Identification of potential transcriptionally active Copia LTR retrotransposons in Eucalyptus

Background Long Terminal Repeat retrotransposons (LTR-RTs) represent the most abundant genomic component in all plant genomes thus far investigated. They are transposable elements that replicate through a “copy/paste” mechanism that relies on reverse transcription and integration of a RNA intermediate. Plant LTR-RTs can be divided in two major superfamilies: Copia and Gypsy[1]. LTR-RTs have impact on genome size variation, as well as in the expression of adjacent genes in their host genomes, providing a “genomic plasticity” [2]. Their transcription was believed to be extremely repressed in plants. However, despite their potential mutagenic and deleterious effects, LTR-RTs were proven to be transcriptionally active in several plant species [3]. Eucalyptus is one of the most commercially important forest genus in the world, due to their superior growth, broad adaptability and multipurpose wood properties. Most molecular studies in Eucalyptus are focused on cellulose production and wood development, and there are few works on genome composition, structure and evolution. Pinus and Populus, the tree genera with most available genomic resources, have several works analyzing their repertoire of LTR-RTs [i. e 4, 5], but only one study characterized LTR-RTs in Eucalyptus[6], with no detailed manual checking or phylogenetic analysis. Here, we used FOREST database as a starting point to identify transcriptionally active Copia LTR-RTs in Eucalyptus, that were further analyzed regarding their in silico expression, evolutionary diversity, and distribution in public genomic databases. Methods A previous survey with 88 CopiaLTR-RTs from diverse plants defined six major common evolutionary Copialineages [7]. The 22 Arabidopsis thaliana families analyzed in that study were used as queries to the identify EucalyptusEST sequences related to Copiaelements in FORESTS database [8], by tBLASTx (e-value >1e-50). Sequences were then analyzed in RepBase [9] to confirm their similarity to Copia LTR-RTs. EucalyptusESTs with >200bp of copia-like retrotransposon fragments were used to identify complete copies in Eucalyptusgrandis genome v 1.0 in a BLASTn search (identity >80%; in a region >250bp). We picked up 10000bp surrounding the aligned region, that were analyzed using LTR-Finder [10] and LTR_STRUC [11]. Full-length LTR-RTs were then used as queries in GenBank to retrieve related EucalyptusEST sequences (>200bp; >80% identity). Phylogenetic analyses using the reverse transcriptase of these elements (alignment in MUSCLE, Maximimum Likelihood method, bootstrap 1000 replicates) were done using MEGA 5.01 [12].

Getting In and Out of Mitosis

Mitosis is the process of one cell dividing into two replicate cells. This process is a universal one, occurring throughout the phyla. Mitosis is a fundamental process. Without it, life ceases to exist. A series of preparatory steps must take place before a cell enters mitosis, and these steps must be undone to exit mitosis. The cell has a nucleus which contains the genetic material, the DNA, as chromosomes packaged with proteins. Before the cell undergoes mitosis, the cell must make two copies of its DNA so that each daughter cell has a complete copy of the genetic material. At the onset of mitosis the nuclear envelope dissolves, and each chromosome lines up with its copy. The chromosomes are connected to proteins known as the mitotic spindle, which in turn are connected to two centrosomes at the two opposite poles of the cell. At the climax of mitosis, the two chromosome copies are pulled apart and each copy is assigned to opposite daughter cells. This is how cell inheritance works. The information on how to direct these dividing cells into making a human being or any organism is contained in those chromosomes. The whole point of cell division is to distribute the DNA molecules (the chromosomes) to each daughter cell accurately and equally. When that goes wrong and a cell has lost genetic material or has received a surplus of genetic material, the result may be cell death, a defective cell, or cancer. During mitosis, under light microscopy, it seems at first that nothing is happening. Suddenly, the cell splits into two daughter cells followed by another period of quiescence. It is as if a switch is turned on and then turned off again. An on/off mechanical switch, like a light switch, may look very simple from the outside, but it has many intricate parts inside. So too, the biological switch which controls mitosis has very intricate inner workings. This article explores these inner workings.

Soybean Plastidal Omega‐3 Fatty Acid Desaturase Genes GmFAD7 and GmFAD8: Structure and Expression

ABSTRACTWe characterized soybean [Glycine max (L.) Merr.] FAD7 and FAD8 gene structure and expression responses to temperature and pathogen stress to compare and contrast these features to those reported for higher plant plastidal omega‐3 (ω‐3) desaturases. We found that the genomic structure and deduced amino acid sequence of soybean FAD7 and FAD8 are similar to other higher plant plastidal ω‐3 desaturases: eight exons and seven introns, predicted proteins of 453 amino acid residues containing three conserved histidine motifs, amino terminal chloroplast transit peptides, and molecular masses of 51.3 and 51.4 kDa, respectively. GmFAD7 has 76% amino acid sequence identity to GmFAD8. Two complete copies of GmFAD7, one on chromosome 18 and one on chromosome 7, and two complete copies of GmFAD8, one on chromosome 3 and one on chromosome 1 of the ‘Williams 82’ soybean genome, were found with strong sequence similarity to GmFAD7 and GmFAD8 of cultivar Dare. Dare GmFAD7 transcript expression in leaves remained at a relatively low level and was unaffected by any of the temperature treatments we imposed, but GmFAD8 transcript accumulation was sharply upregulated by a cool temperature (20/16°C day/night) after a 12 h exposure and total linolenic acid as a percent of total leaf fatty acids increased from 60 to about 68% after 48 h at the cool temperature. Inoculation of soybean leaves with the fungal pathogen Cercospora kikuchii differentially upregulated the level of GmFAD7 transcripts to twice that of GmFAD8 by 12 h postinoculation. The response of soybean foliar FAD8 expression and linolenic acid levels to cool temperature was similar to observations in other plants. On the other hand, despite increased soybean FAD7 expression in response to foliar pathogen stress the expected associated increase in foliar linolenic acid was not detected.

The Left Half of the XMRV Retrovirus Is Present in an Endogenous Retrovirus of NIH/3T3 Swiss Mouse Cells

Xenotropic murine leukemia virus-related virus (XMRV) is a gammaretrovirus found in association with human prostate cancer and chronic fatigue syndrome, although these associations are controversial. XMRV shows at most 94% identity to known mouse retroviruses. Here we used XMRV-specific PCR to search for a more closely related source of XMRV in mice. While we could not find a complete copy, we did find a 3,600-bp region of XMRV in an endogenous retrovirus present in NIH/3T3 cells. These results show that XMRV has clear ancestors in mice and highlight another possible source of contamination in PCR assays for XMRV.