[Transcriptome characterization of Ephedra sinica with 454 ESTs].

Using the latest 454 GS FLX platform and Titanium regent, a substantial expressed sequence tag (ESTs) dataset of Ephedra sinica was produced, and the profile of gene expression and function gene of which were investigated. A total of 48 389 reads with an average length of 373 bp were generated. These 454 reads were assembled into 18 801 unigenes, which were all 454 sequencing identified. A total number of 10 531 unigenes(56.0%) were annotated using BLAST searches (E-value≤1×10⁻5) against the Nr, Nt, TAIR, SwissProt and KEGG databases. With respect to genes related to ephedrine biosynthesis, 19 unigenes(encoding 9 enzymes) were found. A total of 97 putative genes encoding cytochrome P450s were also discovered. Data presented in this study will provide an important resource for the scientific community that is interested in the functional genomics and secondary metabolism of E. sinica.

Microbial diversity in four Mediterranean irciniid sponges.

This paper describes a dataset of microbial communities from four different sponge species: Irciniaoros (Schmidt, 1864), Irciniavariabilis (Schmidt, 1862), Sarcotragusspinosulus Schmidt, 1862 and Sarcotragusfasciculatus (Pallas, 1766). The examined sponges all belong to Demospongiae (Class); Keratosa (Subclass); Dictyoceratida (Order); Irciniidae (Family). Samples were collected by scuba diving at depths between 6-14 m from two sampling sites of rocky formations at the northern coast of Crete (Cretan Sea, eastern Mediterranean) and were subjected to metabarcoding for the V5-V6 region of the 16S rRNA gene.

Low-depth shotgun sequencing resolves complete mitochondrial genome sequence of Labeo rohita.

Labeo rohita, popularly known as rohu, is a widely cultured species in whole Indian subcontinent. In the present study, we used in-silico approach to resolve complete mitochondrial genome of rohu. Low-depth shotgun sequencing using Roche 454 GS FLX (Branford, Connecticut, USA) followed by de novo assembly in CLC Genomics Workbench version 7.0.4 (Aarhus, Denmark) revealed the complete mitogenome of L. rohita to be 16 606 bp long (accession No. KR185963). It comprised of 13 protein-coding genes, 22 tRNAs, 2 rRNAs and 1 putative control region. The gene order and organization are similar to most vertebrates. The mitogenome in the present investigation has 99% similarity with that of previously reported mitogenomes of rohu and this is also evident from the phylogenetic study using maximum-likelihood (ML) tree method. This study was done to determine the feasibility, accuracy and reliability of low-depth sequence data obtained from NGS platform as compared to the Sanger sequencing. Thus, NGS technology has proven to be competent and a rapid in-silico alternative to resolve the complete mitochondrial genome sequence, thereby reducing labors and time.

DNA-Based Characterization and Identification of Arbuscular Mycorrhizal Fungi Species.

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts of most land plants. They have great ecological and economic importance as they can improve plant nutrition, plant water supply, soil structure, and plant resistance to pathogens. We describe two approaches for the DNA-based characterization and identification of AMF, which both can be used for single fungal spores, soil, or roots samples and resolve closely related AMF species: (a) Sanger sequencing of a 1.5 kb extended rDNA-barcode from clone libraries, e.g., to characterize AMF isolates, and (b) high throughput 454 GS-FLX+ pyrosequencing of a 0.8 kb rDNA fragment, e.g., for in-field monitoring.

Very high resolution single pass HLA genotyping using amplicon sequencing on the 454 next generation DNA sequencers: Comparison with Sanger sequencing.

Compared to Sanger sequencing, next-generation sequencing offers advantages for high resolution HLA genotyping including increased throughput, lower cost, and reduced genotype ambiguity. Here we describe an enhancement of the Roche 454 GS GType HLA genotyping assay to provide very high resolution (VHR) typing, by the addition of 8 primer pairs to the original 14, to genotype 11 HLA loci. These additional amplicons help resolve common and well-documented alleles and exclude commonly found null alleles in genotype ambiguity strings. Simplification of workflow to reduce the initial preparation effort using early pooling of amplicons or the Fluidigm Access Array™ is also described. Performance of the VHR assay was evaluated on 28 well characterized cell lines using Conexio Assign MPS software which uses genomic, rather than cDNA, reference sequence. Concordance was 98.4%; 1.6% had no genotype assignment. Of concordant calls, 53% were unambiguous. To further assess the assay, 59 clinical samples were genotyped and results compared to unambiguous allele assignments obtained by prior sequence-based typing supplemented with SSO and/or SSP. Concordance was 98.7% with 58.2% as unambiguous calls; 1.3% could not be assigned. Our results show that the amplicon-based VHR assay is robust and can replace current Sanger methodology. Together with software enhancements, it has the potential to provide even higher resolution HLA typing.

Development of 14 microsatellite markers in the Queensland koala (Phascolarctos cinereus adustus) using next generation sequencing technology.

We report the development of 14 new microsatellite markers in the Queensland koala (Phascolarctos cinereus adustus). Ten unrelated Queensland koala individuals from the San Diego Zoo, USA, were genotyped. The number of alleles per locus ranged from 2 to 7, with an average of 5.14 alleles per locus. Across all loci, the average observed and expected heterozygosity values were both 0.69. These polymorphic microsatellite loci will be useful for genetic studies relevant to the conservation of the koala, a species listed as vulnerable.

Development of microsatellite markers for two Australian Persoonia (Proteaceae) species using two different techniques.

PREMISE OF THE STUDY: Microsatellite markers were developed and cross-species transferability assessed for two Persoonia species to evaluate genetic diversity and population genetic structure of these broadly distributed southwest Australian tree species. • METHODS AND RESULTS: Microsatellite-enriched libraries and 454 GS-FLX shotgun sequencing were used to identity nine microsatellite loci for P. elliptica (one 454; eight cloning) and six for P. longifolia (three 454; three cloning). These loci were screened for variation in individuals from populations in southwestern Australia. In P. elliptica, observed and expected heterozygosities ranged from 0.46 to 0.93 and 0.42 to 0.88, respectively. For P. longifolia, observed and expected heterozygosities ranged from 0.04 to 0.88 and 0.04 to 0.84, respectively. • CONCLUSIONS: The microsatellites identified in this study will enable the examination of population and spatial structuring of genetic diversity in P. elliptica and P. longifolia, two priority species for mine site restoration in southwestern Australia.

Isolation, via 454 sequencing, and characterization of microsatellites for Vachellia farnesiana (Fabaceae: Mimosoideae).

PREMISE OF THE STUDY: We isolated 15 polymorphic microsatellite markers from Vachellia farnesiana for use in population genetic studies to determine the native range of the species. • METHODS AND RESULTS: Initially, 454 shotgun sequencing was used to identify and design primers for 68 microsatellite loci. Of these, we trialed 47 loci in the target species, and 42 (89%) amplified a product of expected size. Fifteen of the 47 loci were screened for variation in 21 individuals from the native range of V. farnesiana in southern Mexico and 20 from northwestern Australia. Fourteen loci were polymorphic, with observed heterozygosity ranging from 0.026 to 1.00 (mean = 0.515) and two to 12 alleles per locus (average = 5.2). Cross-amplification was successful in four to 11 loci in three other Vachellia species. • CONCLUSIONS: The new microsatellite loci will be useful in understanding genetic variation and investigating the role of human-mediated dispersal in the current distribution of V. farnesiana.

Microsatellite primers identified by 454 sequencing in the floodplain tree species Eucalyptus victrix (Myrtaceae).

PREMISE OF THE STUDY: Microsatellite primers were developed for Eucalyptus victrix (Myrtaceae) to evaluate the population and spatial genetic structure of this widespread northwestern Australian riparian tree species, which may be impacted by hydrological changes associated with mining activity. • METHODS AND RESULTS: 454 GS-FLX shotgun sequencing was used to obtain 1895 sequences containing putative microsatellite motifs. Ten polymorphic microsatellite loci were identified and screened for variation in individuals from two populations in the Pilbara region. Observed heterozygosities ranged from 0.44 to 0.91 (mean: 0.66) and the number of alleles per locus ranged from five to 25 (average: 11). • CONCLUSIONS: These microsatellite loci will be useful in future studies of population and spatial genetic structure in E. victrix, and inform the development of seed sourcing strategies for the species.

Development of microsatellite loci for the riparian tree species Melaleuca argentea (Myrtaceae) using 454 sequencing.

PREMISE OF THE STUDY: Microsatellite primers were developed for Melaleuca argentea (Myrtaceae) to evaluate genetic diversity and population genetic structure of this broadly distributed northern Australian riparian tree species. • METHODS AND RESULTS: 454 GS-FLX shotgun sequencing was used to obtain 5860 sequences containing putative microsatellite motifs. Two multiplex PCRs were optimized to genotype 11 polymorphic microsatellite loci. These loci were screened for variation in individuals from two populations in the Pilbara region, northwestern Western Australia. Overall, observed heterozygosities ranged from 0.27 to 0.86 (mean: 0.52) and the number of alleles per locus ranged from two to 13 (average: 4.3). • CONCLUSIONS: These microsatellite loci will be useful in future studies of the evolutionary history and population and spatial genetic structure in M. argentea, and inform the development of seed sourcing strategies for the species.

Development and multiplexed amplification of SSR markers for Thuja occidentalis (Cupressaceae) using shotgun pyrosequencing.

PREMISE OF THE STUDY: Sixteen novel, polymorphic, multiplexed microsatellite loci were developed for eastern white cedar (Thuja occidentalis) using simple sequence repeat (SSR)-enriched shotgun pyrosequencing. • METHODS AND RESULTS: Sixteen loci were tested on a panel of 24 individuals from different populations. The number of observed alleles ranged from four to 22. Four sets of multiplex PCR for the 16 loci were then carried out on 60 individuals of two populations from islands of FERLD Duparquet Forest, Canada. Mean number of alleles, observed heterozygosity, and expected heterozygosity were respectively 5.75, 0.594, and 0.574 for Island 58, and 5.50, 0.704, and 0.624 for Island 134. • CONCLUSIONS: Four sets of multiplex microsatellite loci can be used for future genetic studies, which includes investigating genetic diversity and structure, and fragmentation and regeneration studies.

Allele identification for transcriptome-based population genomics in the invasive plant Centaurea solstitialis.

Transcriptome sequences are becoming more broadly available for multiple individuals of the same species, providing opportunities to derive population genomic information from these datasets. Using the 454 Life Science Genome Sequencer FLX and FLX-Titanium next-generation platforms, we generated 11-430 Mbp of sequence for normalized cDNA for 40 wild genotypes of the invasive plant Centaurea solstitialis, yellow starthistle, from across its worldwide distribution. We examined the impact of sequencing effort on transcriptome recovery and overlap among individuals. To do this, we developed two novel publicly available software pipelines: SnoWhite for read cleaning before assembly, and AllelePipe for clustering of loci and allele identification in assembled datasets with or without a reference genome. AllelePipe is designed specifically for cases in which read depth information is not appropriate or available to assist with disentangling closely related paralogs from allelic variation, as in transcriptome or previously assembled libraries. We find that modest applications of sequencing effort recover most of the novel sequences present in the transcriptome of this species, including single-copy loci and a representative distribution of functional groups. In contrast, the coverage of variable sites, observation of heterozygosity, and overlap among different libraries are all highly dependent on sequencing effort. Nevertheless, the information gained from overlapping regions was informative regarding coarse population structure and variation across our small number of population samples, providing the first genetic evidence in support of hypothesized invasion scenarios.