Molecular Ecology Resources

Publisher: Blackwell Publishing

Description

  • Impact factor
    7.43
  • 5-year impact
    4.15
  • Cited half-life
    3.00
  • Immediacy index
    0.85
  • Eigenfactor
    0.02
  • Article influence
    1.20
  • Other titles
    Molecular ecology resources (Online)
  • ISSN
    1755-0998
  • OCLC
    190864867
  • Material type
    Document, Periodical, Internet resource
  • Document type
    Internet Resource, Computer File, Journal / Magazine / Newspaper

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Blackwell Publishing

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    • Articles in some journals can be made Open Access on payment of additional charge
    • 'Blackwell Publishing' is an imprint of 'Wiley-Blackwell'
  • Classification
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Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: This study represents the first comprehensive molecular assessment of freshwater fishes and lampreys from Germany. We analyzed COI sequences for almost 80% of the species mentioned in the current German Red List. In total, 1056 DNA barcodes belonging to 92 species from all major drainages were used to i) build a reliable DNA barcode reference library, ii) test for phylogeographic patterns, iii) check for the presence of barcode gaps between species, and iv) evaluate the performance of the barcode index number (BIN) system, available on the Barcode of Life Database. For over 78% of all analysed species DNA barcodes are a reliable means for identification, indicated by the presence of barcode gaps. An overlap between intra- and interspecific genetic distances was present in 19 species, six of which belong to the genus Coregonus. The Neighbour-Joining phenogram showed 60 non-overlapping species clusters and three singleton species, which were related to 63 separate BIN numbers. Furthermore, Barbatula barbatula, Leucaspius delineatus, Phoxinus phoxinus and Squalius cephalus exhibited remarkable levels of cryptic diversity. In contrast, eleven clusters showed haplotype sharing, or low levels of divergence between species, hindering reliable identification. The analysis of our barcode library together with public data resulted in 89 BINs, of which 56% showed taxonomic conflicts. Most of these conflicts were caused by the use of synonymies, inadequate taxonomy or misidentifications. Moreover, our study increased the number of potential alien species in Germany from 14 to 21 and is therefore a valuable groundwork for further faunistic investigations. This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
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    ABSTRACT: Single-nucleotide polymorphisms (SNPs) offer numerous advantages over anonymous markers such as microsatellites, including improved estimation of population parameters, finer-scale resolution of population structure, and more precise genomic dissection of quantitative traits. However, many SNPs are needed to equal the resolution of a single microsatellite, and reliable large-scale genotyping of SNPs remains a challenge in non-model species. Here, we document the creation of a 9K Illumina Infinium BeadChip for polar bears (Ursus maritimus), which will be used to investigate: 1) the fine-scale population structure among Canadian polar bears, and 2) the genomic architecture of phenotypic traits in the Western Hudson Bay subpopulation. To this end, we used restriction-site associated DNA (RAD) sequencing from 38 bears across their circumpolar range, as well as blood/fat transcriptome sequencing of 10 individuals from Western Hudson Bay. 6000 RAD SNPs and 3000 transcriptomic SNPs were selected for the chip, based primarily on genomic spacing and gene function respectively. Of the 9000 SNPs ordered from Illumina, 8042 were successfully printed, and—after genotyping 1450 polar bears—5441 of these SNPs were found to be well clustered and polymorphic. Using this array, we show rapid linkage disequilibrium decay among polar bears, we demonstrate that in a subsample of 78 individuals, our SNPs detect known genetic structure more clearly than 24 microsatellites genotyped for the same individuals, and that these results are not driven by the SNP ascertainment scheme. Here we present one of the first large-scale genotyping resources designed for a threatened species.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
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    ABSTRACT: Null alleles are alleles that for various reasons fail to amplify in a PCR assay. The presence of null alleles in microsatellite data is known to bias the genetic parameter estimates. Thus, efficient detection of null alleles is crucial, but the methods available for indirect null-allele detection return inconsistent results. Here, our aim was to compare different methods for null-allele detection, to explain their respective performance, and to provide improvements. We applied several approaches to identify the ‘true’ null alleles based on the predictions made by five different methods, used either individually or in combination. First, we introduced simulated ‘true’ null alleles into 240 population datasets and applied the methods to measure their success in detecting the simulated null alleles. The single best performing method was ML- ML-NullFreq_frequency. Furthermore, we applied different noise reduction approaches to improve the results. For instance, by combining the results of several methods we obtained more reliable results than by using a single one. Rule-based classification was applied to identify population properties linked to the false discovery rate. Rules obtained from the classifier described which population genetic estimates and loci characteristics that were linked to the success of each method. We have shown that by simulating ‘true’ null alleles into a population dataset we may define a null allele frequency threshold, related to a desired true or false discovery rate. Moreover, using such simulated datasets, the expected null allele homozygote frequency may be estimated independently of the equilibrium state of the population.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
  • Lucia R. Weinman, Joseph W. Solomon, Dustin R. Rubenstein
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    ABSTRACT: The development of genetic markers has revolutionized molecular studies within and among populations. Although poly-allelic microsatellites are the most commonly used genetic marker for within-population studies of free-living animals, bi-allelic single nucleotide polymorphisms, or SNPs, have also emerged as a viable option for use in non-model systems. We describe a robust method of SNP discovery from the transcriptome of a non-model organism that resulted in more than 99% of the markers working successfully during genotyping. We then compare the use of 102 novel SNPs with 15 previously-developed microsatellites for studies of parentage and kinship in cooperatively breeding superb starlings (Lamprotornis superbus) that live in highly kin-structured groups. For 95% of the offspring surveyed, SNPs and microsatellites identified the same genetic father, but only when behavioral information about the likely parents at a nest was included to aid in assignment. Moreover, when such behavioral information was available, the number of SNPs necessary for successful parentage assignment was reduced by half. However, in a few cases where candidate fathers were highly related, SNPs did a better job at assigning fathers than microsatellites. Despite high variation between individual pairwise relatedness values, microsatellites and SNPs performed equally well in kinship analyses. This study is the first to compare SNPs and microsatellites for analyses of parentage and relatedness in a species that lives in groups with a complex social and kin structure. It should also prove informative for those interested in developing SNP loci from transcriptome data when published genomes are unavailable.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
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    ABSTRACT: Oxford Nanopore's third-generation, single-molecule sequencing platform promises to decrease costs for reagents and instrumentation. After a two-year hiatus following the initial announcement, the first devices have been released as part of an early access program. We explore the performance of this platform by re-sequencing the lambda phage genome, and amplicons from a snake venom gland transcriptome. Although the handheld MinION sequencer can generate more than 150 megabases of raw data in one run, at most a quarter of the resulting reads map to the reference, with less than average 10% identity. Much of the sequence consists of insertion/deletion errors, or is seemingly without similarity to the template. Using the lambda phage data as an example, although the reads are long, averaging 5kb, at best 890±1,932 bases per mapped read could be matched to the reference without soft clipping. In the course of a 36 hour run on the MinION it was possible to re-sequence the 48kb lambda phage reference at 16x coverage. Currently substantially larger projects would not be feasible using the MinION. Without increases in accuracy, which would be required for applications such as genome scaffolding and phasing, the current utility of the MinION appears limited. Library preparation requires access to a molecular lab, and is of similar complexity and cost to that of other next-generation sequencing platforms. The MinION is an exciting step in a new direction for single-molecule sequencing, though it will require dramatic decreases in error rates before it lives up to its promise.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
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    ABSTRACT: Analyses of pairwise relatedness represent a key component to addressing many topics in biology. However, such analyses have been limited because most available programs provide a means to estimate relatedness based on only a single estimator, making comparison across estimators difficult. Second, all programs to date have been platform-specific, working only on a specific operating system. This has the undesirable outcome of making choice of relatedness estimator limited by operating system preference, rather than being based on scientific rationale. Here we present a new R package, called related, that can calculate relatedness based on seven estimators, can account for genotyping errors, missing data, and inbreeding, and can estimate 95% confidence intervals. Moreover, simulation functions are provided that allow for easy comparison of the performance of different estimators, and for analyses of how much resolution to expect from a given data set. Because this package works in R, it is platform-independent. Combined, this functionality should allow for more appropriate analyses and interpretation of pairwise relatedness, and will also allow for the integration of relatedness data into larger R workflows.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
  • M J Karam, F Lefèvre, M Bou Dagher‐Kharrat, S Pinosio, G G Vendramin
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    ABSTRACT: We combined Restriction site Associated DNA sequencing (RADseq) using a hypomethylation-sensitive enzyme and messenger RNA sequencing (mRNAseq) to develop molecular markers for the 16 Gigabase genome of Cedrus atlantica, a conifer tree species. With each method, Illumina® reads from one individual were used to generate de novo assemblies. SNPs from the RADseq dataset were detected in a panel of one single individual and three pools of three individuals each. We developed a flexible script to estimate the ascertainment bias in SNP detection considering the pooling and sampling effects on the probability of not detecting an existing polymorphism. Gene Ontology (GO) and Transposable Element (TE) search analyses were applied to both datasets. The RADseq and the mRNAseq assemblies represented 0.1% and 0.6% of the genome, respectively. Genome complexity reduction resulted in 17% of the RADseq contigs potentially coding for proteins. This rate was doubled in the mRNAseq dataset, suggesting that RADseq also explores non-coding low repeat regions. The two methods gave very similar GO-slim profiles. As expected, the two assemblies were poor in TE-like sequences (<4% of contigs length). We identified 17,348 single nucleotide polymorphisms (SNPs) in the RADseq dataset and 5,714 simple sequence repeats (SSRs) in the transcriptome. A subset of 282 SNPs was validated using the Fluidigm genotyping technology, giving a conversion rate of 50.4%, falling within the expected range for conifers. Increasing sample size had the greatest effect for ascertainment bias reduction. These results validated the utility of the RADseq approach for highly complex genomes such as conifers.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 09/2014;
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    ABSTRACT: A DNA barcode is a short piece of DNA sequence used for species determination and discovery. The internal transcribed spacer (ITS/ITS2) region has been proposed as the standard DNA barcode for fungi and seed plants, and has been widely used in DNA barcoding analyses for other biological groups, e.g. algae, protists, and animals. The ITS region consists of both ITS1 and ITS2 regions. Here, a large scale meta-analysis was carried out to compare ITS1 and ITS2 from three aspects: PCR amplification, DNA sequencing and species discrimination, in terms of the presence of DNA barcoding gaps, species discrimination efficiency, sequence length distribution, GC content distribution and primer universality. In total, 85,345 sequence pairs in ten major groups of eukaryotes, including ascomycetes, basidiomycetes, liverworts, mosses, ferns, gymnosperms, monocotyledons, eudicotyledons, insects, and fishes, covering 611 families, 3,694 genera, and 19,060 species, were analyzed. Using similarity-based methods, we calculated species discrimination efficiencies for ITS1 and ITS2 in all major groups, families, and genera. Using Fisher's exact test, we found that ITS1 has significantly higher efficiencies than ITS2 in 17 of the 47 families and 20 of the 49 genera, which are sample-rich. By in silico PCR amplification evaluation, primer universality of the extensively applied ITS1 primers was found superior to that of ITS2 primers. Additionally, shorter length of amplification product and lower GC content were discovered to be two other advantages of ITS1 for sequencing. In summary, ITS1 represents a better DNA barcode than ITS2 for eukaryotic species.
    Molecular Ecology Resources 09/2014;
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    ABSTRACT: This is the first de novo transcriptome and complete mitochondrial genome of an Antarctic sea urchin species sequenced to date. Sterechinus neumayeri is an Antarctic sea urchin and a model species for ecology, development, physiology, and global change biology. To identify transcripts important to ocean acidification and thermal stress, this transcriptome was created pooling thirteen larval samples representing developmental stages on day 11 (late gastrula), 19 (early pluteus), and 30 (mid pluteus) maintained at three CO2 levels (421, 652, and 1071 μatm) as well as four additional heat shocked samples. The normalized cDNA pool was sequenced using emulsion PCR (pyrosequencing) resulting in 1.34M reads with an average read length of 492 base pairs. 40,994 isotigs were identified, averaging 1188bp with a median coverage of 11x. Additional primer design and gap sequencing was required to complete the mitochondrial genome. The mitogenome of S. neumayeri is a circular DNA molecule with a length of 15,684 bp that contains all 37 genes normally found in metazoans. We detail the main features of the transcriptome and the mitogenome architecture and investigate the phylogenetic relationships of S. neumayeri within Echinoidea. In addition, we provide comparative analyses of S. neumayeri with its closest relative, Strongylocentrotus purpuratus, including a list of potential ocean acidification gene targets. The resources described here will support a variety of quantitative (genomic, proteomic, multistress and comparative) studies to interrogate physiological responses to OA and other stressors in this important Antarctic calcifier.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: The genus Curcuma L. is commonly used as spices, medicines, dyes and ornamentals. Owing to its economic significance and lack of clear-cut morphological differences between species, this genus is an ideal case for developing DNA barcodes. In the present study, four chloroplast DNA regions (matK, rbcL, trnH-psbA, trnL-F) and one nuclear region (ITS2) were generated for forty-four Curcuma species and five species from closely related genera, represented by 96 samples. PCR amplification success rate, intra- and inter-specific genetic distance variation, and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in matK (89.7%), rbcL (100%), trnH-psbA (100%), trnL-F (95.7%) and ITS2 (82.6%) regions. The results further showed that four candidate chloroplast barcoding regions (matK, rbcL, trnH-psbA and trnL-F) yield no barcode gaps, indicating that the genus Curcuma represents a challenging group for DNA barcoding. The ITS2 region presented large interspecific variation, and provided the highest correct identification rates (46.7%) based on BLASTClust method among the five regions. However, the ITS2 only provided 7.9% based on NJ tree method. An increase in discriminatory power needs the development of more variable markers.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: Evolutionary timescales can be estimated from genetic data using phylogenetic methods based on the molecular clock. To account for molecular rate variation among lineages, a number of relaxed-clock models have been developed. Some of these models assume that rates vary among lineages in an autocorrelated manner, so that closely related species share similar rates. In contrast, uncorrelated relaxed clocks allow all of the branch-specific rates to be drawn from a single distribution, without assuming any correlation between rates along neighboring branches. There is uncertainty about which of these two classes of relaxed-clock models is more appropriate for biological data. We present an R package, NELSI, that allows the evolution of DNA sequences to be simulated according to a range of clock models. Using data generated by this package, we assessed the ability of two Bayesian phylogenetic methods to distinguish among different relaxed-clock models and to quantify rate variation among lineages. The results of our analyses show that rate autocorrelation is typically difficult to detect, even when there is complete taxon sampling. This provides a potential explanation for past failures to detect rate autocorrelation in a range of data sets.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: RAD-tag is a powerful tool for high-throughput genotyping. It relies on PCR amplification of the starting material, following enzymatic digestion and sequencing adaptor ligation. Amplification introduces duplicate reads into the data, which arise from the same template molecule and are statistically non-independent, potentially introducing errors into genotype calling. In shotgun sequencing data duplicates are removed by filtering reads starting at the same position in the alignment. However, restriction enzymes target specific locations within the genome, causing reads to start in the same place, and making it difficult to estimate the extent of PCR duplication. Here we introduce a slight change to the Illumina sequencing adaptor chemistry, appending a unique four-base tag to the first index read, which allows duplicate discrimination in aligned data. This approach was validated on the Illumina MiSeq platform, using double-digest libraries of ants (Wasmannia auropunctata) and yeast (Saccharomyces cerevisiae) with known genotypes, producing modest though statistically significant gains in the odds of calling a genotype accurately. More importantly, removing duplicates also corrected for strong sample-to-sample variability of genotype calling accuracy seen in the ant samples. For libraries prepared from low-input degraded museum bird samples (Mixornis gularis), which had low complexity, having been generated from relatively few starting molecules, adaptor tags show that virtually all of the genotypes were called with inflated confidence as a result of PCR duplicates. Quantification of library complexity by adaptor tagging does not significantly increase the difficulty of the overall workflow or its cost, but corrects for differences in quality between samples, and permits analysis of low-input material.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: Complex microbial communities typically contain a large number of low abundance species, which collectively, comprise a considerable proportion of the community. This “rare biosphere” has been speculated to contain keystone species and act as a repository of genomic diversity to facilitate community adaptation. Many environmental microbes are currently resistant to cultivation, and can only be accessed via culture-independent approaches. To enhance our understanding of the role of the rare biosphere, we aimed to improve their metagenomic representation using DNA normalisation methods, and assess normalisation success via shotgun DNA sequencing. A synthetic metagenome was constructed from the genomic DNA of five bacterial species, pooled in a defined ratio spanning three orders of magnitude. The synthetic metagenome was fractionated and thermally re-natured, allowing the most abundant sequences to hybridise. Double-stranded DNA was removed either by hydroxyapatite chromatography, or by a duplex-specific nuclease (DSN). The chromatographic method failed to enrich for the genomes present in low starting abundance, whereas the DSN method resulted in all genomes reaching near equimolar abundance. The representation of the rarest member was increased by approximately 450-fold. De novo assembly of the normalised metagenome enabled up to 18.0% of genes from the rarest organism to be assembled, in contrast to the un-normalised sample, where genes were not able to be assembled at the same sequencing depth. This study has demonstrated that the application of normalisation methods to metagenomic samples is a powerful tool to enrich for sequences from rare taxa, which will shed further light on their ecological niches.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: Since its introduction in 2003, DNA barcoding has proven to be a promising method for the identification of many taxa, including mosquitoes (Diptera: Culicidae). Many mosquito species are potential vectors of pathogens and correct identification in all life stages is essential for effective mosquito monitoring and control. To use DNA barcoding for species identification, a reliable and comprehensive reference database of verified DNA sequences is required. Hence, DNA sequence diversity of mosquitoes in Belgium was assessed using a 658 bp fragment of the mitochondrial cytochrome oxidase I (COI) gene and a reference dataset was established. Most species appeared as well-supported clusters. Intraspecific Kimura two-parameter (K2P) distances averaged 0.7%, and the maximum observed K2P distance was 6.2% for Aedes koreicus. A small overlap between intra-and interspecific K2P distances for congeneric sequences was observed. Overall, the identification success using Best Match and the Best Close Match criteria was high, i.e. above 98%. No clear genetic division was found between the closely related species Aedes annulipes and Aedes cantans, which can be confused using morphological identification only. The members of the Anopheles maculipennis complex, i.e. Anopheles maculipennis s.s. and An. messeae, were weakly supported as monophyletic taxa. The current study showed that DNA barcoding offers a reliable framework for mosquito species identification in Belgium except for some closely related species.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: Phylin is a package for the R programming environment which offers different methods to spatially interpolate genetic information from phylogeographic data. These interpolations can be used to predict the spatial occurrence of different lineages within a phylogeny using a modified method of kriging, which allows the usage of a genetic distance matrix to derive a model of spatial dependence. Phylin improves the available methods to generate interpolated surfaces from a phylogenetic trees by assessing the autocorrelation structure of the genetic information, interpolating the genetic data based on a statistical model, estimating the uncertainty of the predictions, and identifying lineage occurrence and contact zones probability without projection of pairwise genetic distances into midpoints between sample locations. The package also includes methods to plot interpolation surfaces and provide summary tables from the generated data and models. We provide an example of the usefulness of this tool by inferring the spatial occurrence of distinct historical evolutionary lineages of the Lataste's viper (Vipera latastei Bosca, 1878) in the Iberian Peninsula, and identifying potential contact areas. The maps of phylogenetic patterns obtained with these methods provide a spatial context to test hypotheses related to processes underlying the geographic distribution of genetic diversity and to inform conservation planning.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: Wolves and dogs provide a paradigmatic example of the ecological and conservation implications of hybridization events between wild and domesticated forms. However, our understanding of such implications has been traditionally hampered by both high genetic similarity and the difficulties in obtaining tissue samples (TS), which limit our ability to assess ongoing hybridization events. To assess the occurrence and extension of hybridization in a pack of wolf-dog hybrids in Northwestern Iberia, we compared the power of 52 nuclear markers implemented on TS with a subset of 13 ancestry informative markers (AIMs) typed in non-invasive samples (NIS). We demonstrate that the 13 AIMs are as accurate as the 52 markers that were chosen without regard to the power to differentiate between wolves and dogs, also having the advantage of being rapidly screened on NIS. The efficiency of AIMs significantly outperformed ten random sets of similar size and an additional commercial set of 18 markers. Bayesian clustering analysis implemented on AIMs and NIS identified nine hybrids, two wolves and two dogs. Four hybrids were unambiguously assigned to F1xWolf backcrosses. Our approach (AIMs + NIS) overcomes previous difficulties related to sample availability and informative power of markers, allowing a quick identification of wolf-dog hybrids in the first phases of hybridization episodes. This provides managers with a reliable tool to evaluate hybridization, and estimate the success of their actions. This approach may be easily adapted for other pairs of wild/domesticated species, thus improving our understanding of the introgression of domestication genes into natural populations.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 08/2014;
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    ABSTRACT: The rapid growth rate of human population, along with the public health crisis encountered in many regions, particularly in developing world, create an urgent need for the discovery of alternative drugs. Because medicinal plants are not distributed randomly across lineages, it has been suggested that phylogeny along with traditional knowledge of plant uses can guide the identification of new medicinally useful plants. In this study, we combined different statistical approaches to test for phylogenetic signal in 33 categories of plant uses in South Africa. Depending on the null models considered, we found evidence for signal in up to 45% of plant use categories, indicating the need for multiple tests combination to maximise the chance of discovering new medicinal plants when applying a phylogenetic comparative approach. Furthermore, although there was no signal in the diversity of medicinal uses – i.e. total number of medicinal uses recorded for each plant – our results indicate that taxa that are evolutionarily closely related have significantly more uses than those that are evolutionarily isolated. Our study therefore provides additional support to the body of literature that advocates for the inclusion of phylogeny in bioscreening medicinal flora for the discovery of alternative medicines.
    Molecular Ecology Resources 07/2014;
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    ABSTRACT: Pigs from Asia and Europe were independently domesticated from ~9,000 years ago. During this period, strong artificial selection has led to dramatic phenotypic changes in domestic pigs. However, the genetic basis underlying these morphological and behavioural adaptations is relatively unknown, particularly for indigenous Chinese pigs. Here, we performed a genome-wide analysis to screen 196 regions with selective sweep signals in Tongcheng pigs, which are a typical indigenous Chinese breed. Genes located in these regions have been found to be involved in lipid metabolism, melanocyte differentiation, neural development, and other biological processes, which coincide with the evolutionary phenotypic changes in this breed. A synonymous substitution, c.669T>C, in ESR1, which co-localises with a major quantitative trait locus for litter size, shows extreme differences in allele frequency between Tongcheng pigs and wild boars. Notably, the variant C allele in this locus exhibits high allele frequency in most Chinese populations, suggesting a consequence of positive selection. Five genes (PRM1, PRM2, TNP2, GPR149 and JMJD1C) related to reproductive traits were found to have high haplotype similarity in Chinese breeds. Two selected genes, MITF and EDNRB, are implied to shape the two-end black colour trait in Tongcheng pig. Subsequent SNP microarray studies of five Chinese white-spotted breeds displayed a concordant signature at both loci, suggesting that these two genetic loci are responsible for colour variations in Chinese breeds. Utilising massively parallel sequencing, we characterised the candidate sites that adapt to artificial and environmental selections during the Chinese pig domestication. This study provides fundamental proof for further research on the evolutionary adaptation of Chinese pigs.This article is protected by copyright. All rights reserved.
    Molecular Ecology Resources 07/2014;

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