Project description:We describe an application of deep sequencing and de novo assembly of short RNA reads to investigate small interfering (si)RNAs mediated immunity in leaf samples from eight tree taxa naturally occurring in Wytham Woods, Oxfordshire, UK. BLAST search for homologues of contigs in the GenBank identified siRNA populations against a number of RNA viruses and a Ty1-copia retrotransposons in these tree species. Small RNA sequencing and de novo assembly
Project description:This work describes the molecular mechanisms of meiotic maturation and cell cycle in the starfish Astropecten Aranciacus. The study has been conducted assembling a de-novo transcriptome from the different cellular stages: oocytes, egg, zygote and early embryos. Differential expression analysis followed by rtPCR are used to assess the validity of the assembly.
Project description:Long-term perturbation of de novo chromatin assembly during DNA replication has profound effects on epigenome maintenance and cell fate. The early mechanistic origin of these defects is unknown. Here, we combine acute degradation of Chromatin Assembly Factor 1 (CAF-1), a key player in de novo chromatin assembly, with single-cell genomics, quantitative proteomics, and live-microscopy to uncover these initiating mechanisms in human cells. CAF-1 loss immediately slows down DNA replication speed and renders nascent DNA hyper-accessible. A rapid cellular response, distinct from canonical DNA damage signaling, is triggered and lowers histone mRNAs. As a result, histone variants usage and their modifications are altered, limiting transcriptional fidelity and delaying chromatin maturation within a single S-phase. This multi-level response induces a cell-cycle arrest after mitosis. Our work reveals the immediate consequences of defective de novo chromatin assembly during DNA replication, explaining how at later times the epigenome and cell fate can be altered.
Project description:We describe an application of deep sequencing and de novo assembly of short RNA reads to investigate small interfering (si)RNAs mediated immunity in leaf samples from eight tree taxa naturally occurring in Wytham Woods, Oxfordshire, UK. BLAST search for homologues of contigs in the GenBank identified siRNA populations against a number of RNA viruses and a Ty1-copia retrotransposons in these tree species.
Project description:Orchidaceae are renowned for their spectacular flowers as well as other reproductive and ecological adaptations. After the genome of the tropical epiphytic orchid Phalaenopsis equestris was sequenced, we combined Trinity data for de novo assembly and Illumina HiSeq1500 data for RNA-Seq analysis to characterize the transcriptomes of four different organs for a better understanding of the molecular mechanisms driving these characteristics. We present four de novo assembled transcripts reconstructed from RNA collected from the root, stem, leaf, and flower of Phalaenopsis equestris. These sets of transcripts greatly enrich the available data for Phalaenopsis equestris. Here, we present two databases, and each dataset allows for a different type of search for candidate homologues. The first dataset consists of the sets of assembled unigenes, which enable a sequence-based search. A comprehensive analysis of the assembled unigenes revealed the unigenes from root, stem, leaf, and flower with high e-values aligned versus the Nr, Swiss-Port, KEGG, COG, and GO database, respectively. This analysis enabled the production of a second database, which includes sequences correlated with annotated transcript names as well as the confidence of the best hit from BLAST.
Project description:We have performed deep RNA-Seq and de novo transcriptome assembly at different stages of mouse oogenesis. This revealed thousands of novel non-annotated genes as well as alternative promoters for ~10% of reference genes expressed in oocytes, a large fraction of which coincide with transposable elements of the MaLR and ERVK families. We defined the oocyte DNA methylation landscape as composed of large-scale hyper- and hypo-methylated domains. Correlation with our transcriptome assembly revealed that transcription correlates accurately with DNA methylation and potentially account for ~85-90% of the DNA methylome. RNA-Seq in mouse oocytes at different stages of folliculogenesis
Project description:We reported an atlas of de novo-defined, full-length macaque gene models on the basis of single molecule long-read transcriptome sequencing (Iso-seq).
Project description:We developed a software package STITCH (https://github.com/snijderlab/stitch) to perform template-based assembly of de novo peptide reads from antibody samples. As a test case we generated de novo peptide reads from protein G purified whole IgG from COVID-19 patients.