Project description:This SuperSeries is composed of the following subset Series: GSE27022: Microarray studies of darkness stress and bleaching in the Caribbean coral Acropora palmata GSE27024: Microarray studies of darkness stress and bleaching in the Caribbean coral Montastraea faveolata Refer to individual Series
Project description:With the creation of accurate, chromosome-scale genomes, the next challenge facing the genomics community is the accurate idenfication of transcriptional units, distinguishing them from aberrant transcriptional noise. This has proven to be a challenge as annotation by traditional means, such as short read RNA-seq followed by transcriptome assembly, which is prone to the generation of in-silico artifacts. To address this issue, we took advantage of epigenomic data in the form of ChIP-seq to unbiasedly annotate plant genomes and identify potential annotation issues, as well as identify novel genes. Histone modifications appear in the genome in a reproducible and predictable manner, making them an ideal resource to use in annotation. Trimethylation of histone 3 lysine 4 (H3K4me3), as well as acetylation of histone 3 lysine 56 are well documented to coincide with initiation of transcription by polymerase II (Pol II) at promoter sequences. These initiation marks, paired with marks deposited across the gene body during transcriptional elongation, such as histone 3 lysine 36 tri-methylation (H3K36me3) and histone 3 lysine 4 mono-methylation (H3K4me1), offer a framework to begin identifying complete transcriptional units. We leveraged these data on a genome-wide scale, allowing for identification of annotations discordant with empirical data. In total, 13,159 potential annotation issues were found in Zea mays across three different tissues, which were corroborated using complementary RNA-based approaches. Upon correction and validation, genes were extended by an average of 2,128 base pairs, and the length of discovered novel genes was 1,962 base pairs. Application of this method to five additional plant genomes revealed a variety of novel gene annotations, including 13,836 in Asparagus officianalis, 2,724 in Setaria viridis, 2,446 in Sorghum bicolor, 8,631 in Glycine max, and 2,585 in Phaseolous vulgaris.
Project description:We collected (Illumina) RNA-seq data (polyadenylated RNA fraction) for a number of tissue samples from common marmoset and elephant. We developed a subtraction approach based on male/female RNA-seq data, Illumina genomic data and available genomes to identify and assemble Y transcripts. For marmoset samples, we added Y coding genes and noncoding sequences to the reference genomes in order to assess their expression levels. We then mapped all RNA-seq reads with TopHat 1.4.0 and used Cufflinks 2.0.0 (all mapped reads, embedded multi-read and fragment bias correction) to calculate the FPKM (Fragments Per Kilobase of transcript per Million mapped reads) values for all genes in the genomes with our refined annotations. Sequence and expression levels of reconstructed Y-linked genes
Project description:We collected (Illumina) RNA-seq data (polyadenylated RNA fraction) for a number of tissue samples from common marmoset and elephant. We developed a subtraction approach based on male/female RNA-seq data, Illumina genomic data and available genomes to identify and assemble Y transcripts. For marmoset samples, we added Y coding genes and noncoding sequences to the reference genomes in order to assess their expression levels. We then mapped all RNA-seq reads with TopHat 1.4.0 and used Cufflinks 2.0.0 (all mapped reads, embedded multi-read and fragment bias correction) to calculate the FPKM (Fragments Per Kilobase of transcript per Million mapped reads) values for all genes in the genomes with our refined annotations.
Project description:Purpose: Saccharomyceatacea yeast are intron-poor species and they contain on average 300 introns in their genomes. We designed RNAseq experiment to investigate if splicing patterns in related yeast species are similar. Methods: Total RNA was extracted from wild type cells and processed by the RiboMinus Transcriptome Isolation Kit for Yeast and Bacteria (Invitrogen) to deplete the rRNA. cDNA libraries were prepared according to manufacturer's protocol and sequenced by SOLiD. Sequence reads were filtered and processed by TopHat. Results: We found 216, 163, 200 and 155 predicted introns with canonical splice signals in S. cerevisiae, S. kudriavzevii, S. bayanus and N. castellii respectively. Three introns in S. cerevisiae, four in S. bayanus and ten in S. castellii are novel compared to Saccharomyces Genome Database (SGD) annotations. The expression of introns and splicing shows very high correlation between species. Conclusion: Transcripts with introns in yeast species tested show similar levels of expression and splicing. We found few novel introns, which are conserved in yeast genomes.
Project description:Fireflies and their fascinating luminous courtships have inspired centuries of scientific study. Today firefly luciferase is widely used in biotechnology, but the evolutionary origin of their bioluminescence remains unclear. To shed light on this long-standing question, we sequenced the genomes of two firefly species that diverged over 100 million-years-ago: the North American Photinus pyralis and Japanese Aquatica lateralis. To compare bioluminescent origins, we also sequenced the genome of a related click-beetle, the Caribbean Ignelater luminosus, with bioluminescent biochemistry near-identical to fireflies, but anatomically unique light organs, suggesting the intriguing but contentious hypothesis of parallel gains of bioluminescence. Our analyses support two independent gains of bioluminescence between fireflies and click-beetles, and provide new insights into the genes, chemical defenses, and symbionts that evolved alongside their luminous lifestyle.