Poly(A) tail length change of miRNA targets in HeLa cells
ABSTRACT: MicroRNA induces deadenylation of its targets according to the current model in the scientific community, but this model is based on the studies of a few individual genes. We tested the model by examining the global effect of miRNA on poly(A) tail of the targets. Synthetic miR-1 mimic was transfected into HeLa cells, and the poly(A) length was measured by TAIL-seq. Deadenylation of miR-1 targets was evident as early as 3 hours post-transfection without a significant change in mRNA level. After 6 or 9 hours, target mRNA level was substantially downregulated. Therefore, although there are some exceptions, our result confirms that, in general, miRNA indeed induces deadenylation. Furthermore, our kinetic global analysis confirms that deadenylation precedes mRNA decay. Four culture dishes of HeLa cells were treated with miR-1 all together, then collected and prepared for sequencing after different time of incubation (0, 3, 6, and 9 hours post-transfection)
Project description:Eukaryotic mRNAs are subject to multiple types of tailing which critically influence mRNA stability and translatability. To investigate RNA tails at the genomic scale, we previously developed TAIL-seq, but its low sensitivity precluded its application to biological materials of minute quantity. In this study, we report a new version of TAILseq (mRNA TAIL-seq or mTAIL-seq) with enhanced sequencing depth for mRNAs (by ~1000 fold compared to the previous version). The improved method allows us to investigate the regulation of poly(A) tail in Drosophila oocytes and embryos. We find that maternal mRNAs are polyadenylated mainly during late oogenesis, prior to fertilization, and that further modulation occurs upon egg activation. Wispy, a noncanonical poly(A) polymerase, adenylates the vast majority of maternal mRNAs with a few intriguing exceptions such as ribosomal protein transcripts. By comparing mTAILseq data with ribosome profiling data, we find a strong coupling between poly(A) tail length and translational efficiency during egg activation. Our data suggest that regulation of poly(A) tail in oocytes shapes the translatomic landscape of embryos, thereby directing the onset of animal development. By virtue of the high sensitivity, low cost, technical robustness, and broad accessibility, mTAIL-seq will be a potent tool to improve our understanding of mRNA tailing in diverse biological systems. Ten separate sets of TAIL-seq experiments were performed. Two sets of HeLa cells are untransfected normal cells. Eight sets of fly sample include a pair of wild type and mutant.
Project description:To obtain a global view of mRNA uridylation in Arabidopsis, we generated TAIL-seq libraries from WT plants, urt1 and xrn4 single mutants, and urt1 xrn4 double mutant. The TAIL-seq protocol was recently developed to deep-sequence the 3' ends of RNAs (Chang et al., 2014). We generated TAIL-seq libraries from WT plants, urt1 and xrn4 single mutants, and urt1 xrn4 double mutant.
Project description:Poly(A) tails enhance the stability and translation of most eukaryotic messenger RNAs, but difficulties in globally measuring poly(A)-tail lengths have impeded greater understanding of poly(A)-tail function. Here we describe poly(A)-tail length profiling by sequencing (PAL-seq) and apply it to measure tail lengths of millions of individual RNAs isolated from yeasts, cell lines, Arabidopsis thaliana leaves, mouse liver, and zebrafish and frog embryos. Poly(A)-tail lengths were conserved between orthologous mRNAs, with mRNAs encoding ribosomal proteins and other 'housekeeping' proteins tending to have shorter tails. As expected, tail lengths were coupled to translational efficiencies in early zebrafish and frog embryos. However, this strong coupling diminished at gastrulation and was absent in non-embryonic samples, indicating a rapid developmental switch in the nature of translational control. This switch complements an earlier switch to zygotic transcriptional control and explains why the predominant effect of microRNA mediated deadenylation concurrently shifts from translational repression to mRNA destabilization. 64 samples from a variety of species
Project description:The Poly(A)-Tail focused RNA-seq, or PAT-seq approach was utilised to determine the gene expression, poly(A)-site and polyadenylation state of the transcriptome of early C. elegans embryos having been depleated for a series of RNA binding proteins. Namely; pos-1 and mex-5 were independently knocked down using dsRNA expressing E. coli HT115(DE3) fed to ~100,000 starved/synchronized L1 larvae. When half of the population reached adulthood and half were still in the L4 stage, worms were bleached and embryos harvested and stored in Trizol. This ensured an enrichment of early embryos between 1 and 24 cell stage. mex-6(pk440) were synchronized and grown on OP50 until the same time point and embryos harvested in the same manner. Since prolonged gld-3 and gld-2 RNAi result in sterility, starved/synchronized L1 larvae were fed diluted OP50 (200uL of concentrated OP50 diluted in 2mL of M9 and starved L1s) for 16 hours. At that point the OP50 had been mostly consumed by the larvae and concentrated gld-3 or gld-2 dsRNA expressing E. coli were added to the plates. When half of the population reached adulthood and half were still in the L4 stage, worms were bleached and embryos harvested and stored in Trizol. Total RNA was isolated using standard procedures. Analysis of poly(A) dynamics in early C. elegans embryos reponding to depletion of specific RNA binding proteins and adneylation state regulators
Project description:The post-transcriptional fate of messenger RNAs (mRNAs) is largely dictated by their 3' untranslated regions (3'UTRs), which are defined by cleavage and polyadenylation (CPA) of pre-mRNAs. We used poly(A)-position profiling by sequencing (3P-Seq) to map poly(A) sites at eight developmental stages and tissues in the zebrafish. Analysis of over 60 million 3P-Seq reads substantially increased and improved existing 3'UTR annotations, resulting in confidently identified 3'UTRs for more than 78.79% of the annotated protein-coding genes in zebrafish. Most zebrafish genes undergo alternative CPA with more than a thousand genes using different dominant 3'UTRs at different stages. 3'UTRs tend to be shortest in the ovaries and longest in the brain. Isoforms with some of the shortest 3'UTRs are highly expressed in the ovary yet absent in the maternally contributed RNAs of the embryo, perhaps because their 3'UTRs are too short to accommodate a uridine-rich motif required for stability of the maternal mRNA. At two hours post-fertilization, thousands of unique poly(A) sites appear at locations lacking a typical polyadenylation signal, which suggests a wave of widespread cytoplasmic polyadenylation of mRNA degradation intermediates. Our insights into the identities, formation, and evolution of zebrafish 3'UTRs provide a resource for studying gene regulation during vertebrate development. 3P-Seq was used to map the 3' ends of protein-coding genes in the zebrafish genome
Project description:Agarwood is an expensive resinous heartwood derived from the wounded Aquilaria plants. To identify the primary genes that maybe related to agarwood formation, we sequenced 2 cDNA libraries generated from healthy and wounded A. sinensis (Lour.) Gilg. A total of 89,137 unigenes with an average length of 678.65 bp were obtained, and they were annotated in detail at bioinformatics levels. Of those associated with agarwood formation, 30 putatively encoded enzymes in the sesquiterpene biosynthesis pathway, a handful of transcription factors, and protein kinases related to wound signal transduction. Three full-length cDNAs of sesquiterpene synthases (ASS1-3) were cloned and expressed in Escherichia coli, and enzyme assays revealed that they are active enzymes, with the major products being δ-guaiene. A methyl jasmonate (MJ) induction experiment revealed that the expression of ASS was significantly induced by MJ, and the production of sesquiterpenes was elevated accordingly. The expression of some transcription factors and protein kinases, especially MYB4, WRKY4, MPKK2 and MAPK2, was also induced by MJ and coordinated with ASS expression, suggesting they maybe positive regulators of ASS. This study provides extensive transcriptome information for Aquilaria spp. and valuable clues for elucidating the mechanism of wound-induced agarwood sesquiterpenes biosynthesis and their regulation. healthy and wounded stems of three-year-old A. sinensis trees
Project description:We performed a genome-wide deep sequencing analysis of the microRNAs abundant in mesenchymal stem cells (MSCs) derived from murine brown adipose tissue and in in vitro differentiated mature brown adipocytes. Several microRNAs were identified as differentially regulated when comparing datasets from MSCs vs. mature fat cells. These microRNAs may have an implication in the regulation of adipogenesis as well as thermogenesis in brown adipose tissue (BAT). Examination of BAT-derived MSCs (BAT-MSC; 1 sample) and in vitro differentiated mature brown fat cells (BAT-DIFF; 1 sample) vertis biotechnologie AG, D-85354 Freising, Germany (library construction and sequencing)
Project description:We report the profiling of small RNAs from Nanoarchaeum equitans by high-throughput sequencing. Over 16 million Illumina HiSeq 2000 reads were mapped to the 490,885-nucleotide small genome of Nanoarchaeum equitans. The mapping allowed the identification of highly abundant C/D box sRNAs and crRNAs in an organism that has to import its nucleotides from Ignicoccus hospitalis. The precursor tRNA halves of trans-spliced tRNAs were identified. Analysis of small RNA from one sample of Nanoarchaeum equitans.
Project description:We report the profiling of small RNAs from Methanopyrus kandleri by high throughput sequencing. Over 83 million Illumina Hi Seq2000 reads were obtained for six independent RNA libraries. The reads were mapped to the M. kandleri AV19 genome (Genbank: NC_003551, 1694969 bp). The small RNome of M. kandleri was analyzed. Analysis of small RNome from six Methanopyrus kandleri RNA samples
Project description:Systems responses of mature leaves from 4 reference cultivars of a larger collection of European potato cultivars (Solanum tuberosum L.) are investigated by metabolome profiling and RNA-Sequencing. The chosen reference cultivars, Milva, Alegria, Desiree, and Saturna, vary in ascending order in regard to drought tolerance. Systems analyses are based on 3 independent field trials and 3 paralleled greenhouse trials. Robust responses across all cultivars and conditions to natural seasonal drought stress comprise proline, raffinose, galactinol, arabitol, arabinonic acid, chlorogenic acid, and 102 transcripts which consist to a high proportion of heat shock proteins and genes with signaling or regulatory functions, such as a homolog of abscisic acid receptor PYL4. Constitutive differences of the tolerant cultivars, Desiree and Saturna, compared to the sensitive cultivars include arbutin (hydroquinone-beta-D-glucopyranoside), octopamine (p-hydroxyphenylethanolamine), ribitol and 248 differential transcripts. Many of these transcripts are disease related, receptor kinases, or regulatory genes, for example a homolog of the Arabidopsis FOUR LIPS MYB-regulator of stomatal cell proliferation. Functional enrichment analyses imply that heat stress is a major acclimation component of potato leaves to agronomical relevant drought stress. Enhanced leaf heat stress is a result of drought caused by loss of transpiration cooling. This effect and CO2-limitation are the main dilemmas of drought- or ABA-induced stomatal closure. Constitutive differences between tolerant and sensitive cultivars indicate partially synergistic interactions of drought and biotic stress responses. We suggest that drought tolerance of the potato reference cultivars may be caused by general resistance mechanisms which are part of previously selected pathogen tolerance. Transcriptome profiling by RNA-sequencing of 48 leaf samples from 4 potato cultivars grown under control or drought stress conditions in 6 independent experiments