Project description:The genus Flaveria has been extensively used as a model to study the evolution of C4 photosynthesis as it contains both C3 and C4 species as well as a number of species that exhibit intermediate types of photosynthesis. The current phylogenetic tree of the Flaveria genus contains 21 of the 23 known Flaveria species and has been constructed using a combination of morphologicial data and three non-coding DNA sequences (nuclear encoded ETS, ITS and chloroplast encoded trnl-F). However, recent studies have suggested that phylogenetic trees inferred using a small number of molecular sequences may often be incorrect. Moreover, studies in other genera have often shown substantial differences between trees inferred using morphological data and those using molecular sequence. To provide new insight into the phylogeny of the genus Flaveria we utilize RNA-Seq data to construct a multi-gene concatenated phylogenetic tree of 17 Flaveria species. Furthermore, we use this new data to identify 14 C4 specific non-synonymous mutation sites, 12 of which (86%) can be independently verified by public sequence data. We propose that the data collection method provided in this study can be used as a generic method for facilitating phylogenetic tree reconstruction in the absence of reference genomes for the target species. 18 Flaveria sample including 11 species are sequenced, other three samples were also sequenced as out-group. In all, 21 samples.
Project description:The genus Flaveria has been extensively used as a model to study the evolution of C4 photosynthesis as it contains both C3 and C4 species as well as a number of species that exhibit intermediate types of photosynthesis. The current phylogenetic tree of the Flaveria genus contains 21 of the 23 known Flaveria species and has been constructed using a combination of morphologicial data and three non-coding DNA sequences (nuclear encoded ETS, ITS and chloroplast encoded trnl-F). However, recent studies have suggested that phylogenetic trees inferred using a small number of molecular sequences may often be incorrect. Moreover, studies in other genera have often shown substantial differences between trees inferred using morphological data and those using molecular sequence. To provide new insight into the phylogeny of the genus Flaveria we utilize RNA-Seq data to construct a multi-gene concatenated phylogenetic tree of 17 Flaveria species. Furthermore, we use this new data to identify 14 C4 specific non-synonymous mutation sites, 12 of which (86%) can be independently verified by public sequence data. We propose that the data collection method provided in this study can be used as a generic method for facilitating phylogenetic tree reconstruction in the absence of reference genomes for the target species.
2015-01-08 | GSE54339 | GEO
Project description:Complete chloroplast genome sequences and comparative analysis of three Vaccinium species
Project description:Gigantopithecus blacki was a giant hominid that inhabited Southeast Asia during the Pleistocene. Its evolutionary relationship to other great ape species, and their divergence during the Middle and Late Miocene (16-5.3 Mya), remains disputed. In part, this is due to the absence of cranial and postcranial remains and size-induced allometry. Proposed hypothesis on the phylogenetic positions of Gigantopithecus have therefore been wide-ranging among hominoids, but none has received independent validation based on molecular evidence. To clarify the phylogenetic placement of Gigantopithecus blacki, we retrieved enamel proteome sequences from a 1.9 million years (Mya) old molar found in Chuifeng Cave, China. We demonstrate that Gigantopithecus is most closely related to orangutans (genus Pongo). We also estimate the Gigantopithecus-Pongo divergence to about 10-12 Mya, implying its speciation is part of the Miocene radiation of great apes. These sequences are approximately 6 times older, in a normalized thermal context, than any previously published mammalian proteome or genome. The survival of an Early Pleistocene dental enamel proteome in the subtropics further expands the scope of palaeoproteomic analysis into geographic areas and time periods previously considered incompatible with biomolecular preservation.
Project description:Salvia is an important genus from the Lamiaceae with approximately 1000 species distributed globally. Several Salvia species are commercially important because of their medicinal and culinary properties. We report the construction of the first fingerprinting array for Salvia species enriched with polymorphic and divergent DNA sequences and demonstrate the potential of this array for fingerprinting several economically important members of this genus. In order to generate the Salvia Subtracted Diversity Array (SDA), a Suppression Subtractive Hybridization (SSH) was performed between a pool of ten Salvia species and a pool of non-angiosperm and angiosperms (excluding the Lamiaceae) to selectively isolate Salvia-specific sequences. A total of 285 subtracted genomic DNA (gDNA) fragments were amplified and arrayed. DNA fingerprints were obtained for fifteen Salvia genotypes including three that were not part of the original subtraction pool. Hierarchical cluster analysis indicated that the Salvia-specific SDA was capable of differentiating closely related species of S. officinalis and S. miltiorrhiza and was also able to reveal genetic relationships consistent with geographical origins. Species-specific features were also found for S. elegans, S. officinalis, S. sclarea, S. przewalskii and S. runcinata.
Project description:Hyperthermophilic bacteria of the genus Thermotoga are known to utilize a wide range of simple and complex polysaccharides. T. maritima's transcriptional response to a variety of mono- and poly-saccharides was previously studied to assign functions to genes involved in carbohydrate uptake and utilization. To compare and contrast closely-related members of the Thermotoga genus, a four-species microarray was developed by expanding a whole genome T. maritima array to include unique genes from three other species (T. neapolitana, T. petrophila, and T. sp. RQ2). This multi-species array was used to investigate the diversity of the genus, specifically the response of each of the four species to a mixture of polysaccharides (galactomannan, glucomannan, xylan, pectin, lichenan, and carboxymethyl cellulose).
Project description:Spotted hyena (Crocuta crocuta) is the only extant species of the genus Crocuta, which once occupied a much wider range during the Pliocene and Pleistocene. However, its origin and evolutionary history is somewhat contentious due to discordances being found between morphological, nuclear, and mitochondrial data. Due to the limited molecular data from east Asian Crocuta, and the difficulty of extracting ancient DNA from this area, here we present proteomic analysis of cave hyenas from three locations in northern China. This marks the first proteomic data generated from cave hyenas, adding new molecular data to the east Asian populations. Phylogenetic analysis based on these protein sequences reveals two different groups of cave hyenas in east Asia, one of which could not be distinguished from modern spotted hyenas from northern Africa, tentatively the result of previously suggested gene flow between these lineages. With developments of instrumentation and analytical methods, proteomics holds promising potential for the phylogenetic reconstruction of ancient fauna previously thought to be unreachable using ancient DNA.