25 research outputs found

    Decreased Genetic Drift under the Overlapping Conservation

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    contributed equally to this work. A B S T R A C T S In order to understand the genetic drift under closed population using equaled family size, two overlapping conservation methods proposed (increment and decrement) were introduced to compare with the discrete population. Finally, the article showed body weight controlled by hundred loci having average gene effect. For increment, the second generation had the parents composed of 400 original population and 100 from first generation; the third population consisted of 300 original population, 100 from first generation and 100 from second generation. The fourth population was composed 200 from original population, 100 from first population, 100 from second population, 100 from third population, and 100 from the fourth population. The fifth population was achieved by randomly selecting 100 from each population. For decrement, the method has the opposite direction. For different population, both more than one thousand and less than family sizes 10 have the stable gene frequency despite the different initial gene frequency and sex ratio. Despite several generations were maintained together, less than 5 generations increment conservation can make the gene frequency improved to less than 0.5, while more than 0.5, increment conservation can make them decrease to less than 5 generations and reach the stable higher gene frequency in the following generations. Generally, less than 0.4 gene frequency can use in the increment conservation. More than 0.7, you can use the decrement method. When 100 loci which have average gene effect and random initial gene frequency were assumed, both increment and decrement conservation methods can keep the phenotype stable

    Combined QTL and Genome Scan Analyses With the Help of 2b-RAD Identify Growth-Associated Genetic Markers in a New Fast-Growing Carp Strain

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    Common carp is one of the oldest and most popular cultured freshwater fish species both globally and in China. In a previous study, we used a carp strain with a long breeding tradition in China, named Huanghe, to create a new fast-growing strain by selection for fast growth for 6 years. The growth performance at 8 months of age has been improved by 20.84%. To achieve this, we combined the best linear unbiased prediction with marker-assisted selection techniques. Recent progress in genome-wide association studies and genomic selection in livestock breeding inspired common carp breeders to consider genome-based breeding approaches. In this study, we developed a 2b-RAD sequence assay as a means of investigating the quantitative trait loci in common carp. A total of 4,953,017,786 clean reads were generated for 250 specimens (average reads/specimen = 19,812,071) with BsaXI Restriction Enzyme. From these, 56,663 SNPs were identified, covering 50 chromosomes and 3,377 scaffolds. Principal component analysis indicated that selection and control groups are relatively clearly distinct. Top 1% of Fst values was selected as the threshold signature of artificial selection. Among the 244 identified loci, genes associated with sex-related factors and nutritional metabolism (especially fat metabolism) were annotated. Eighteen QTL were associated with growth parameters. Body length at 3 months of age and body weight (both at 3 and 8 months) were controlled by polygenic effects, but body size (length, depth, width) at 8 months of age was controlled mainly by several loci with major effects. Importantly, a single shared QTL (IGF2 gene) partially controlled the body length, depth, and width. By merging the above results, we concluded that mainly the genes related to neural pathways, sex and fatty acid metabolism contributed to the improved growth performance of the new Huanghe carp strain. These findings are one of the first investigations into the potential use of genomic selection in the breeding of common carp. Moreover, our results show that combining the Fst, QTL mapping and CRISPR–Cas9 methods can be an effective way to identify important novel candidate molecular markers in economic breeding programs

    Transgenic common carp do not have the ability to expand populations.

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    The ecological safety of transgenic organisms is an important issue of international public and political concern. The assessment of ecological risks is also crucial for realizing the beneficial industrial application of transgenic organisms. In this study, reproduction of common carp (Cyprinus carpio, CC) in isolated natural aquatic environments was analyzed. Using the method of paternity testing, a comparative analysis was conducted on the structure of an offspring population of "all-fish" growth hormone gene-transgenic common carp (afgh-CC) and of wild CC to evaluate their fertility and juvenile viability. Experimental results showed that in a natural aquatic environment, the ratio of comparative advantage in mating ability of afgh-CC over wild CC was 1∶1, showing nearly identical mating competitiveness. Juvenile viability of afgh-CC was low, and the average daily survival rate was less than 98.00%. After a possible accidental escape or release of transgenic CC into natural aquatic environments they are unable to monopolize resources from eggs of natural CC populations, leading to the extinction of transgenic CC. Transgenic CC are also unlikely to form dominant populations in natural aquatic environments due to their low juvenile viability. Thus, it is expected that the proportion of afgh-CC in the natural environment would remain low or gradually decline, and ultimately disappear

    RNA-seq profiles from grass carp tissues after reovirus (GCRV) infection based on singular and modular enrichment analyses

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    Hemorrhagic disease of the grass carp, Ctenopharyngodon idella, is a fatal disease in fingerlings and yearlings caused by a reovirus, GCRV. RNA-seq data from four diseased grass carp tissues (gill, intestine, liver and spleen) were obtained at 2 h before and six times after (2 h, 24 h, 48 h, 72 h, 96 h and 120 h) GCRV challenge. A total of 7.25 +/- 0.18 million (M) clean reads and 3.53 +/- 0.37 M unique reads were obtained per RNA-seq analysis. Compared with controls, there were 9060 unique differentially expressed genes (DEGs) in the four tissues at the six time points post-GCRV challenge. Hierarchical clustering analysis of the DEGs showed that the data from the six time points fell into three branches: 2 h, 24 h/48 h, and 72 h/96 h/120 h. Singular (SEA) and modular enrichment analyses of DEGs per RNA-seq dataset were performed based on gene ontology. The results showed that immune responses occurred in all four tissues, indicating that GCRV probably does not target any tissue specifically. Moreover, during the course of disease, disturbances were observed in lipid and carbohydrate metabolism in each of the organs. SEA of DEGs based on the Kyoto Encyclopedia of Genes and Genomes database was also performed, and this indicated that the complement system and cellular immunity played an important role during the course of hemorrhagic disease. The qPCR of pooled samples of duplicate challenge experiment were used to confirm our RNA-seq approach. (C) 2014 Elsevier Ltd. All rights reserved

    Primers used for PCR amplification.

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    <p>NOTE:+“m” represents the M13 sequence (CACGACGTTGTAAAACGAC).</p

    pCAgcGH structure diagram.

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    <p>1: carp <i>β-actin</i> gene 5′-flanking sequence; 2: carp <i>β-actin</i> gene first exon; 3: carp <i>β-actin</i> gene first intron; 4: grass carp <i>GH</i> gene sequence; 5: grass carp <i>GH</i> gene 3′-flanking sequence; 6: plasmid pUC118. PF and PR indicate PCR primers of transgenes.</p

    Synthesis of Oleanolic Acid-Dithiocarbamate Conjugates and Evaluation of Their Broad-Spectrum Antitumor Activities

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    Efficient and mild synthetic routes for bioactive natural product derivatives are of current interest for drug discovery. Herein, on the basis of the pharmacophore hybrid strategy, we report a two-step protocol to obtain a series of structurally novel oleanolic acid (OA)-dithiocarbamate conjugates in mild conditions with high yields. Moreover, biological evaluations indicated that representative compound 3e exhibited the most potent and broad-spectrum antiproliferative effects against Panc1, A549, Hep3B, Huh-7, HT-29, and Hela cells with low cytotoxicity on normal cells. In terms of the IC50 values, these OA-dithiocarbamate conjugates were up to 30-fold more potent than the natural product OA. These compounds may be promising hit compounds for the development of novel anti-cancer drugs
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