Project description:<p><em>Tripterygium wilfordii</em> is a vine used in Traditional Chinese Medicine (TCM) from the family Celastraceae. The active ingredient celastrol is a friedelane-type pentacyclic triterpenoid, with a putative role as an anti-tumor, immunosuppression, and obesity agent. Here we reported a reference genome assembly of <em>T. wilfordii</em> with high-quality annotation by using a hybrid sequencing strategy, which obtained a 340.12 Mb total genome size, a contig N50 reaching 3.09 Mb, 31593 structure genes, and the repeat percentage was 44.31%. Comparative evolutional analyses showed that <em>T. wilfordii</em> diverged from species of Malpighiales about 102.4 million years ago. In addition, we successfully anchored 91.02% sequences into 23 pseudochromosomes using Hi-C technology and the super-scaffold N50 reached 13.03 Mb. Based on integration of genome, transcriptome and metabolite analyses, as well as in vivo and in vitro enzyme assays of the two CYP450 genes, <em>TwCYP712K1</em> and <em>TwCYP712K2</em> the second biosynthesis step of celastrol was investigated and elucidated. Syntenic analysis revealed that <em>TwCYP712K1</em> and <em>TwCYP712K2</em> derived from a common ancestor. These results have provided insights into further investigating pathways for celastrol and valuable information to aid the conservation of resources and helped us reveal the evolution of Celastrales.</p>
Project description:Accurate annotation of transcript isoforms is crucial to understand gene functions, but automated methods for reconstructing full-length transcripts from RNA sequencing (RNA-seq) data remain imprecise. We developed Bookend, a software package for transcript assembly that incorporates data from different RNA-seq techniques, with a focus on identifying and utilizing RNA 5′ and 3′ ends. Through end-guided assembly with Bookend we demonstrate that correct modeling of transcript start and end sites is essential for precise transcript assembly. Furthermore, we discovered that utilization of end-labeled reads present in full-length single-cell RNA-seq (scRNA-seq) datasets dramatically improves the precision of transcript assembly in single cells. Finally, we show that hybrid assembly across short-read, long-read, and end-capture RNA-seq datasets from Arabidopsis, as well as meta-assembly of RNA-seq from single mouse embryonic stem cells (mESCs) can produce end-to-end transcript annotations of comparable quality to reference annotations in these model organisms.
Project description:we determine genome-wide binding profiles of a maize CCA1 homolog, ZmCCA1b, in maize inbreds and F1 hybrids at different times of the day. ZmCCA1b is characterized as a central clock regulator gene with evolutionarily conserved molecular and circadian functions and nonadditively expressed in F1 hybrid seedlings. ZmCCA1b binds to over 4,300 target genes in the maize genomes, of which annotation confirms energy metabolic pathways as the main output. We report that an altered temporal binding activity of ZmCCA1b in the hybrid seedlings, which increases expression of carbon fixation genes, increases carbon fixation rates and biomass, demonstrating a novel example of how circadian-regulatory networks directly contribute to growth vigor in maize hybrids. These results collectively offer new insights into clock-mediated regulation of growth vigor in hybrid plants and crops.
Project description:we determine genome-wide binding profiles of a maize CCA1 homolog, ZmCCA1b, in maize inbreds and F1 hybrids at different times of the day. ZmCCA1b is characterized as a central clock regulator gene with evolutionarily conserved molecular and circadian functions and nonadditively expressed in F1 hybrid seedlings. ZmCCA1b binds to over 4,300 target genes in the maize genomes, of which annotation confirms energy metabolic pathways as the main output. We report that an altered temporal binding activity of ZmCCA1b in the hybrid seedlings, which increases expression of carbon fixation genes, increases carbon fixation rates and biomass, demonstrating a novel example of how circadian-regulatory networks directly contribute to growth vigor in maize hybrids. These results collectively offer new insights into clock-mediated regulation of growth vigor in hybrid plants and crops. Profiling genome-wide binding events of ZmCCA1b in the maize inbreds and F1 hybrids at ZT3, ZT9 and ZT15 using chromatin immunoprecipitation followed by deep sequencing (ChIP-seq). 2 biological replicates for each sample were used. Input DNA sample corresponding to each ChIP sample was also sequenced in parallel. We have developed a native antibody for the protein (GRMZM2G014902; epitope: residues 11-77) for the ChIP-seq study.