共查询到20条相似文献，搜索用时 15 毫秒
1.
Lauren C. White Claudia Fontsere Esther Lizano David A. Hughes Samuel Angedakin Mimi Arandjelovic Anne‐Cline Granjon Jrg B. Hans Jack D. Lester M. Timothy Rabanus‐Wallace Carolyn Rowney Veronika Stdele Tomas Marques‐Bonet Kevin E. Langergraber Linda Vigilant 《Molecular ecology resources》2019,19(3):609-622
Large‐scale genomic studies of wild animal populations are often limited by access to high‐quality DNA. Although noninvasive samples, such as faeces, can be readily collected, DNA from the sample producers is usually present in low quantities, fragmented, and contaminated by microorganism and dietary DNAs. Hybridization capture can help to overcome these impediments by increasing the proportion of subject DNA prior to high‐throughput sequencing. Here we evaluate a key design variable for hybridization capture, the number of rounds of capture, by testing whether one or two rounds are most appropriate, given varying sample quality (as measured by the ratios of subject to total DNA). We used a set of 1,780 quality‐assessed wild chimpanzee (Pan troglodytes schweinfurthii) faecal samples and chose 110 samples of varying quality for exome capture and sequencing. We used multiple regression to assess the effects of the ratio of subject to total DNA (sample quality), rounds of capture and sequencing effort on the number of unique exome reads sequenced. We not only show that one round of capture is preferable when the proportion of subject DNA in a sample is above ~2%–3%, but also explore various types of bias introduced by capture, and develop a model that predicts the sequencing effort necessary for a desired data yield from samples of a given quality. Thus, our results provide a useful guide and pave a methodological way forward for researchers wishing to plan similar hybridization capture studies. 相似文献
2.
Cristina Linares Rafel Coma Simone Mariani David Díaz Bernat Hereu Mikel Zabala 《Invertebrate Biology》2008,127(1):1-11
Abstract. Knowledge about early stages of marine sessile invertebrates dispersing by means of free-swimming propagules is fundamental toward understanding their population biology. In this study, we describe and quantify survivorship of early stages of the gorgonian Paramuricea clavata to contribute to the understanding of their implications on population dynamics of this emblematic species of the Mediterranean hard-bottom communities. Spawning was recorded in June for the 3 years studied (2001–2003). High levels of fertilization rate were observed during the main spawning in 2001 and 2002 (62–69%). This appears to be related to the surface brooding mode of development, synchronous spawning, and high fecundity of the species. The timing of development of the blastulae was ∼24 h and the planulae appeared after 48–72 h. In the laboratory, metamorphosis into polyp started between 8 and 25 d, but this timing may have been delayed by lack of unknown appropriate cues for settlement. The behavior of first developed planulae exhibited a marked negative phototaxis that may be a strategy to avoid competition with fast-growing algae on photophilous habitats. Despite the high fertilization rate in P. clavata , laboratory and field experiences indicate that survivorship through the planulae and polyp stages was very low, given that none of the settled polyps survived for >7 months in both experimental years. The low survival of the early stages may help explain the low recruitment rates observed in the field in addition to indicating major limitations for colonization of new areas and for persistence of the local population under disturbances. 相似文献
3.
The presence, genetic identity and diversity of algal endosymbionts (Symbiodinium) in 114 species from 69 genera (20 families) of octocorals from the Great Barrier Reef (GBR), the far eastern Pacific (EP) and the Caribbean was examined, and patterns of the octocoral-algal symbiosis were compared with patterns in the host phylogeny. Genetic analyses of the zooxanthellae were based on ribosomal DNA internal transcribed spacer 1 (ITS1) region. In the GBR samples, Symbiodinium clades A and G were encountered with A and G being rare. Clade B zooxanthellae have been previously reported from a GBR octocoral, but are also rare in octocorals from this region. Symbiodinium G has so far only been found in Foraminifera, but is rare in these organisms. In the Caribbean samples, only Symbiodinium clades B and C are present. Hence, Symbiodinium diversity at the level of phylogenetic clades is lower in octocorals from the Caribbean compared to those from the GBR. However, an unprecedented level of ITS1 diversity was observed within individual colonies of some Caribbean gorgonians, implying either that these simultaneously harbour multiple strains of clade B zooxanthellae, or that ITS1 heterogeneity exists within the genomes of some zooxanthellae. Intracladal diversity based on ITS should therefore be interpreted with caution, especially in cases where no independent evidence exists to support distinctiveness, such as ecological distribution or physiological characteristics. All samples from EP are azooxanthellate. Three unrelated GBR taxa that are described in the literature as azooxanthellate (Junceella fragilis, Euplexaura nuttingi and Stereonephthya sp. 1) contain clade G zooxanthellae, and their symbiotic association with zooxanthellae was confirmed by histology. These corals are pale in colour, whereas related azooxanthellate species are brightly coloured. The evolutionary loss or gain of zooxanthellae may have altered the light sensitivity of the host tissues, requiring the animals to adopt or reduce pigmentation. Finally, we superimposed patterns of the octocoral-algal symbiosis onto a molecular phylogeny of the host. The data show that many losses/gains of endosymbiosis have occurred during the evolution of octocorals. The ancestral state (azooxanthellate or zooxanthellate) in octocorals remains unclear, but the data suggest that on an evolutionary timescale octocorals can switch more easily between mixotrophy and heterotrophy compared to scleractinian corals, which coincides with a low reliance on photosynthetic carbon gain in the former group of organisms. 相似文献
4.
Jiamei Jiang Hao Yuan Xin Zheng Qian Wang Ting Kuang Jingyan Li Junning Liu Shuli Song Weicai Wang Fangyuan Cheng Hongjie Li Junman Huang Chenhong Li 《Ecology and evolution》2019,9(7):3973-3983
Gene capture coupled with the next‐generation sequencing has become one of the preferred methods of subsampling genomes for phylogenomic studies. Many exon markers have been developed in plants, sharks, frogs, reptiles, fishes, and others, but no universal exon markers have been tested in ray‐finned fishes. Here, we identified a suite of “single‐copy” protein‐coding sequence (CDS) markers through comparing eight fish genomes, and tested them empirically in 83 species (33 families and nine orders or higher clades: Acipenseriformes, Lepisosteiformes, Elopomorpha, Osteoglossomorpha, Clupeiformes, Cypriniformes, Gobiaria, Carangaria, and Eupercaria; sensu Betancur et al. 2013). Sorting the markers according to their completeness and phylogenetic decisiveness in taxa tested resulted in a selection of 4,434 markers, which were proven to be useful in reconstructing phylogenies of the ray‐finned fishes at different taxonomic levels. We also proposed a strategy of refining baits (probes) design a posteriori based on empirical data. The markers that we have developed may greatly enrich the batteries of exon markers for phylogenomic study in ray‐finned fishes. 相似文献
5.
Single nucleotide polymorphisms (SNPs) are replacing microsatellites for population genetic analyses, but it is not apparent how many SNPs are needed or how well SNPs correlate with microsatellites. We used data from the gopher tortoise, Gopherus polyphemus—a species with small populations, to compare SNPs and microsatellites to estimate population genetic parameters. Specifically, we compared one SNP data set (16 tortoises from four populations sequenced at 17 901 SNPs) to two microsatellite data sets, a full data set of 101 tortoises and a partial data set of 16 tortoises previously genotyped at 10 microsatellites. For the full microsatellite data set, observed heterozygosity, expected heterozygosity and FST were correlated between SNPs and microsatellites; however, allelic richness was not. The same was true for the partial microsatellite data set, except that allelic richness, but not observed heterozygosity, was correlated. The number of clusters estimated by structure differed for each data set (SNPs = 2; partial microsatellite = 3; full microsatellite = 4). Principle component analyses (PCA) showed four clusters for all data sets. More than 800 SNPs were needed to correlate with allelic richness, observed heterozygosity and expected heterozygosity, but only 100 were needed for FST. The number of SNPs typically obtained from next‐generation sequencing (NGS) far exceeds the number needed to correlate with microsatellite parameter estimates. Our study illustrates that diversity, FST and PCA results from microsatellites can mirror those obtained with SNPs. These results may be generally applicable to small populations, a defining feature of endangered and threatened species, because theory predicts that genetic drift will tend to outweigh selection in small populations. 相似文献
6.
7.
Kirsten A. Ziesemer Jazmín Ramos-Madrigal Allison E. Mann Bernd W. Brandt Krithivasan Sankaranarayanan Andrew T. Ozga Menno Hoogland Courtney A. Hofman Domingo C. Salazar-García Bruno Frohlich George R. Milner Anne C. Stone Mark Aldenderfer Cecil M. Lewis Jr Corinne L. Hofman Christina Warinner Hannes Schroeder 《American journal of physical anthropology》2019,168(3):496-509
8.
Park E Hwang DS Lee JS Song JI Seo TK Won YJ 《Molecular phylogenetics and evolution》2012,62(1):329-345
The phylum Cnidaria is comprised of remarkably diverse and ecologically significant taxa, such as the reef-forming corals, and occupies a basal position in metazoan evolution. The origin of this phylum and the most recent common ancestors (MRCAs) of its modern classes remain mostly unknown, although scattered fossil evidence provides some insights on this topic. Here, we investigate the molecular divergence times of the major taxonomic groups of Cnidaria (27 Hexacorallia, 16 Octocorallia, and 5 Medusozoa) on the basis of mitochondrial DNA sequences of 13 protein-coding genes. For this analysis, the complete mitochondrial genomes of seven octocoral and two scyphozoan species were newly sequenced and combined with all available mitogenomic data from GenBank. Five reliable fossil dates were used to calibrate the Bayesian estimates of divergence times. The molecular evidence suggests that cnidarians originated 741 million years ago (Ma) (95% credible region of 686-819), and the major taxa diversified prior to the Cambrian (543 Ma). The Octocorallia and Scleractinia may have originated from radiations of survivors of the Permian-Triassic mass extinction, which matches their fossil record well. 相似文献
9.
Sphaeralcyon shackletonisp. nov. and Sphaeralcyon scottisp. nov. are described and illustrated from material collected at the Scotia Sea and Weddell Sea on the Polarstern cruises ANT XIX/3 (ANDEEP-I), ANT XIX/5 (LAMPOS), and ANT XXI/2 (BENDEX). With the discovery of Sphaeralcyon shackletoni and S. scotti, three species are now known in the genus Sphaeralcyon, all them reported from the Southern Ocean. The diagnosis of the genus has been slightly modified to accommodate some of the characters of the new species. 相似文献
10.
Sonal Singhal Maggie Grundler Guarino Colli Daniel L. Rabosky 《Molecular ecology resources》2017,17(6):e12-e24
The identification of conserved loci across genomes, along with advances in target capture methods and high‐throughput sequencing, has helped spur a phylogenomics revolution by enabling researchers to gather large numbers of homologous loci across clades of interest with minimal upfront investment in locus design. Target capture for vertebrate animals is currently dominated by two approaches—anchored hybrid enrichment (AHE) and ultraconserved elements (UCE)—and both approaches have proven useful for addressing questions in phylogenomics, phylogeography and population genomics. However, these two sets of loci have minimal overlap with each other; moreover, they do not include many traditional loci that that have been used for phylogenetics. Here, we combine across UCE, AHE and traditional phylogenetic gene locus sets to generate the Squamate Conserved Loci set, a single integrated probe set that can generate high‐quality and highly complete data across all three loci types. We use these probes to generate data for 44 phylogenetically disparate taxa that collectively span approximately 33% of terrestrial vertebrate diversity. Our results generated an average of 4.29 Mb across 4709 loci per individual, of which an average of 2.99 Mb was sequenced to high enough coverage (≥10×) to use for population genetic analyses. We validate the utility of these loci for both phylogenomic and population genomic questions, provide a comparison among these locus sets of their relative usefulness and suggest areas for future improvement. 相似文献
11.
del Gaudio D Fortunato G Borriello M Gili JM Buono P Calcagno G Salvatore F Sacchetti L 《Marine biotechnology (New York, N.Y.)》2004,6(6):511-515
Corallium rubrum taxonomy is based on morphologic criteria; little is known about its genome. We set up a rapid, easy method based on amplified fragment length polymorphism to characterize the genetic patterns of C. rubrum in an attempt to understand better the evolutionary relations between species from diverse geographic areas and to help define migration patterns. Applying this procedure to C. rubrum specimens from Spain and Italy, we identified 6 AFLP amplification fragments common to the 4 coral populations studied and 4 fragments that differentiated between these populations. Using this characterization we were able to plot a genetic identity card of this commercially harvested species, which is also a marker of pollution. 相似文献
12.
Pablo J. López-González 《Helgoland Marine Research》2006,60(1):1-6
Mesogligorgia scotiae gen. nov., sp. nov. is described and illustrated from a colony collected in the Scotia Sea, 2,201–2,213 m in depth, on the ANDEEP-I cruise. The new taxon is placed in the family Plexauridae because of: 1) the presence of a horny axis with a cross-chambered central core and numerous loculi, 2) retractile polyps in calyces with distinct spicular components, and 3) armed polyps with large sclerites with a poorly- developed collaret and eight well-developed points. The irregularly distributed sclerites running along the axis, into a thick mesogloeal coenenchyme, and the elongated spindles with irregular ends are the most distinctive characters of the newly proposed genus. 相似文献
13.
Laura‐Jayne Gardiner Pauline Bansept‐Basler Lisa Olohan Ryan Joynson Rachel Brenchley Neil Hall Donal M. O'Sullivan Anthony Hall 《The Plant journal : for cell and molecular biology》2016,87(4):403-419
Previously we extended the utility of mapping‐by‐sequencing by combining it with sequence capture and mapping sequence data to pseudo‐chromosomes that were organized using wheat–Brachypodium synteny. This, with a bespoke haplotyping algorithm, enabled us to map the flowering time locus in the diploid wheat Triticum monococcum L. identifying a set of deleted genes (Gardiner et al., 2014). Here, we develop this combination of gene enrichment and sliding window mapping‐by‐synteny analysis to map the Yr6 locus for yellow stripe rust resistance in hexaploid wheat. A 110 MB NimbleGen capture probe set was used to enrich and sequence a doubled haploid mapping population of hexaploid wheat derived from an Avalon and Cadenza cross. The Yr6 locus was identified by mapping to the POPSEQ chromosomal pseudomolecules using a bespoke pipeline and algorithm (Chapman et al., 2015). Furthermore the same locus was identified using newly developed pseudo‐chromosome sequences as a mapping reference that are based on the genic sequence used for sequence enrichment. The pseudo‐chromosomes allow us to demonstrate the application of mapping‐by‐sequencing to even poorly defined polyploidy genomes where chromosomes are incomplete and sub‐genome assemblies are collapsed. This analysis uniquely enabled us to: compare wheat genome annotations; identify the Yr6 locus – defining a smaller genic region than was previously possible; associate the interval with one wheat sub‐genome and increase the density of SNP markers associated. Finally, we built the pipeline in iPlant, making it a user‐friendly community resource for phenotype mapping. 相似文献
14.
Emily S. Bellis Reid. B. Edlund Hazel K. Berrios Harilaos A. Lessios Dee R. Denver 《Ecology and evolution》2018,8(11):5413-5426
Rising ocean temperatures associated with global climate change induce breakdown of the symbiosis between coelenterates and photosynthetic microalgae of the genus Symbiodinium. Association with more thermotolerant partners could contribute to resilience, but the genetic mechanisms controlling specificity of hosts for particular Symbiodinium types are poorly known. Here, we characterize wild populations of a sea anemone laboratory model system for anthozoan symbiosis, from contrasting environments in Caribbean Panama. Patterns of anemone abundance and symbiont diversity were consistent with specialization of holobionts for particular habitats, with Exaiptasia pallida/S. minutum (ITS2 type B1) abundant on vertical substrate in thermally stable, shaded environments but E. brasiliensis/Symbiodinium sp. (ITS2 clade A) more common in shallow areas subject to high temperature and irradiance. Population genomic sequencing revealed a novel E. pallida population from the Bocas del Toro Archipelago that only harbors S. minutum. Loci most strongly associated with divergence of the Bocas‐specific population were enriched in genes with putative roles in cnidarian symbiosis, including activators of the complement pathway of the innate immune system, thrombospondin‐type‐1 repeat domain proteins, and coordinators of endocytic recycling. Our findings underscore the importance of unmasking cryptic diversity in natural populations and the role of long‐term evolutionary history in mediating interactions with Symbiodinium. 相似文献
15.
Laura‐Jayne Gardiner Piotr Gawroński Lisa Olohan Thorsten Schnurbusch Neil Hall Anthony Hall 《The Plant journal : for cell and molecular biology》2014,80(5):895-904
Mapping‐by‐sequencing analyses have largely required a complete reference sequence and employed whole genome re‐sequencing. In species such as wheat, no finished genome reference sequence is available. Additionally, because of its large genome size (17 Gb), re‐sequencing at sufficient depth of coverage is not practical. Here, we extend the utility of mapping by sequencing, developing a bespoke pipeline and algorithm to map an early‐flowering locus in einkorn wheat (Triticum monococcum L.) that is closely related to the bread wheat genome A progenitor. We have developed a genomic enrichment approach using the gene‐rich regions of hexaploid bread wheat to design a 110‐Mbp NimbleGen SeqCap EZ in solution capture probe set, representing the majority of genes in wheat. Here, we use the capture probe set to enrich and sequence an F2 mapping population of the mutant. The mutant locus was identified in T. monococcum, which lacks a complete genome reference sequence, by mapping the enriched data set onto pseudo‐chromosomes derived from the capture probe target sequence, with a long‐range order of genes based on synteny of wheat with Brachypodium distachyon. Using this approach we are able to map the region and identify a set of deleted genes within the interval. 相似文献
16.
Here we report primers for 10 microsatellite loci from the Caribbean sea fan coral, Gorgonia ventalina. Primers were tested on 237 genomic DNA extracts taken directly from tissue samples of G. ventalina. All loci were polymorphic with allelic richness ranging from 4 to 52. Expected heterozygosity ranged from 0.14 to 0.96. Preliminary data suggest that these microsatellites will be useful tools for studies of the population genetics of this important Caribbean coral species. 相似文献
17.
Background
Microsatellite loci have high mutation rates and thus are indicative of mutational processes within the genome. By concentrating on the symbiotic and aposymbiotic cnidarians, we investigated if microsatellite abundances follow a phylogenetic or ecological pattern. Individuals from eight species were shotgun sequenced using 454 GS-FLX Titanium technology. Sequences from the three available cnidarian genomes (Nematostella vectensis, Hydra magnipapillata and Acropora digitifera) were added to the analysis for a total of eleven species representing two classes, three subclasses and eight orders within the phylum Cnidaria.Results
Trinucleotide and tetranucleotide repeats were the most abundant motifs, followed by hexa- and dinucleotides. Pentanucleotides were the least abundant motif in the data set. Hierarchical clustering and log likelihood ratio tests revealed a weak relationship between phylogeny and microsatellite content. Further, comparisons between cnidaria harboring intracellular dinoflagellates and those that do not, show microsatellite coverage is higher in the latter group.Conclusions
Our results support previous studies that found tri- and tetranucleotides to be the most abundant motifs in invertebrates. Differences in microsatellite coverage and composition between symbiotic and non-symbiotic cnidaria suggest the presence/absence of dinoflagellates might place restrictions on the host genome.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-939) contains supplementary material, which is available to authorized users. 相似文献18.
Andrea M. Quattrini Brant C. Faircloth Luisa F. Dueñas Tom C. L. Bridge Mercer R. Brugler Iván F. Calixto‐Botía Danielle M. DeLeo Santiago Herrera Simon M. Y. Lee David J. Miller Carlos Prada Gandhi Rádis‐Baptista Catalina Ramírez‐Portilla Juan A. Sánchez Estefanía Rodríguez Catherine S. McFadden 《Molecular ecology resources》2018,18(2):281-295
Anthozoans (e.g., corals, anemones) are an ecologically important and diverse group of marine metazoans that occur from shallow to deep waters worldwide. However, our understanding of the evolutionary relationships among the ~7,500 species within this class is hindered by the lack of phylogenetically informative markers that can be reliably sequenced across a diversity of taxa. We designed and tested 16,306 RNA baits to capture 720 ultraconserved element loci and 1,071 exon loci. Library preparation and target enrichment were performed on 33 taxa from all orders within the class Anthozoa. Following Illumina sequencing and Trinity assembly, we recovered 1,774 of 1,791 targeted loci. The mean number of loci recovered from each species was 638 ± 222, with more loci recovered from octocorals (783 ± 138 loci) than hexacorals (475 ± 187 loci). Parsimony informative sites ranged from 26 to 49% for alignments at differing hierarchical taxonomic levels (e.g., Anthozoa, Octocorallia, Hexacorallia). The per cent of variable sites within each of three genera (Acropora, Alcyonium, and Sinularia) for which multiple species were sequenced ranged from 4.7% to 30%. Maximum‐likelihood analyses recovered highly resolved trees with topologies matching those supported by other studies, including the monophyly of the order Scleractinia. Our results demonstrate the utility of this target‐enrichment approach to resolve phylogenetic relationships from relatively old to recent divergences. Redesigning the baits with improved affinities to capture loci within each subclass will provide a valuable toolset to address systematic questions, further our understanding of the timing of diversifications and help resolve long‐standing controversial relationships in the class Anthozoa. 相似文献
19.
We report on the isolation and characterization of five polymorphic microsatellites in the gorgonian Pseudopterogorgia elisabethae from genomic DNA‐enriched libraries. Forty‐four microsatellites were screened from the libraries with the oligonucleotide probe (CA)12. Five of the screened microsatellites were polymorphic. The levels of polymorphism found in 50 genotyped individuals from a single population suggest that microsatellites are useful tools for the study of genetic variation in gorgonians. These are the first microsatellite loci reported from any gorgonian species. 相似文献
20.
燕麦具有较高的营养价值和保健功能,是一种可用于均衡营养、科学饮食的健康食品,正逐渐受到人们的青睐和认可.基因组学研究有助于燕麦重要农艺性状的定位和克隆,对开发利用燕麦优质种质资源具有重要意义.本文从以下几个方面对燕麦基因组学研究进展进行综述:(1)燕麦属基因组类型、大小及染色体倍性研究;(2)基于多种分子标记手段构建燕... 相似文献