Deep sequencing reveals divergent expression patterns within the small RNA transcriptomes of cultured and vegetative tissues of sugarcane
ABSTRACT: We report the deep sequencing of small RNA populations derived from apex, internode 3, internode 6, internode 16, leaf +3, calli and suspesion cells from sugarcane cultivar Q117 Each vegetative tissue was sampled from three independent field grown plants, pooled and sequenced using the GAIIx platform. Calli and suspension cell cultures were sequenced using the HiSeq 2000 platform.
Project description:we report the identification and sequences of the tRNAome of industrially relevant microorganism Lactococcus lactis Three Next Generation sequencing runs annotated as S1, S2 and S3 were performed. Cells were harvested at exponential phase and tRNA was isolated. S1 and S2 were spiked with Phe-tRNAGAA from yeast and Lys-tRNAUUU from E. coli prior to cell lysis. S3 was spiked with Phe-tRNAGAA from yeast and Lys-tRNAUUU from E. coli before the library preparation to estimate the possible loss of tRNA in the extraction process.
Project description:The recent reports of two circular RNAs (circRNAs) with strong potential to act as microRNA (miRNA) sponges suggest that circRNAs might play important roles in regulating gene expression. However, the global properties of circRNAs are not well understood. We developed a computational pipeline to identify circRNAs and quantify their relative abundance from RNA-seq data. Applying this pipeline to a large set of non-poly(A)-selected RNA-seq data from the ENCODE project, we annotated 7,112 human circRNAs that were estimated to comprise at least 10% of the transcripts accumulating from their loci. Most circRNAs are expressed in only a few cell types and at low abundance, but they are no more cell-type–specific than are mRNAs with similar overall expression levels. Although most circRNAs overlap protein-coding sequences, ribosome profiling provides no evidence for their translation. We also annotated 635 mouse circRNAs, and although 20% of them are orthologous to human circRNAs, the sequence conservation of these circRNA orthologs is no higher than that of their flanking linear exons. The previously proposed miR-7 sponge, CDR1as, is one of only two circRNAs with more miRNA sites than expected by chance, with the next best miRNA-sponge candidate deriving from a primate-specific zinc-finger gene, ZNF91. These results provide a new framework for future investigation of this intriguing topological isoform while raising doubts regarding a biological function of most circRNAs. Examination of 9 samples in 1 cell type Note: The ENCODE data we used are under GEO SuperSeries GSE26284 (all samples labeled "_cell_total"). But they were not used in the processing of the U2OS data.
Project description:PIWI proteins bind to PIWI-interacting RNAs (piRNAs) and play key roles in the biogenesis and functions of piRNAs. It has been reported that PIWI proteins are essential for stem cell self-renewal and germline development in diverse organisms, and are ectopically expressed in multiple forms of cancer. However, the role of PIWI in cancer remains elusive. Here we report that one of the four PIWI proteins in humans, PIWIL4, is highly expressed in both breast cancer tissues and the cytoplasm of MDA-MB-231 cell line derived from breast cancer. Reducing PIWIL4 expression drastically impairs migration ability of MDA-MB-231 cells, significantly increases their apotosis, and mildly affects their proliferation. Our transcriptome and proteome analyses reveal that these functions are at least partially achieved via the PIWIL4 regulation of TGF-beta and FGF signaling pathways and major histocompatibility complex (MHC) class II proteins. These findings suggest that PIWIL4 may serve as a potential therapeutic target for breast cancer. Examination of small RNAs in two conditions
Project description:Homeostatic control mechanisms are essentil to life. One such mechanism, the unfolded protein response (UPR) operates in all eukarytic cells to adjust protein folding capacity of the endoplasmic reticulum (ER) according to need. UPR induction in all eurkarytic cells to date involves Ire1 (kinase/endonuclease transmembrane protein) mediated a non-convential splicing of Hac1/XBP1 mRNA, encoding for a potent transcription factor. UPR induction causes a comprehensive transcriptional upregulation of the folding capacity in the ER. Here we studied the global transcriptional profile of the UPR in fission yeast. Fission yeast lacks a clear homolog of Hac1/XBP1. Instead Ire1 maintains ER homeostasis through two post-transciptional programs: selective mRNA decay and processing of Bip1 mRNA (encoding for a major HS70-familiy member in the ER) thereby stabilizing it. S. pombe cells were grown in liquid medium (YE5S) to OD600=0.25. Cells were treated with or without 2 mM DTT (Dithiothreitol, impairs disulfid bond formation) for 60 min at 30℃. Total RNA was extracted from cells using hot phenol method. PolyA+ mRNA were enriched by two sequential rounds of oligo-dT (Invitrogen) selection. rRNA depletion was performed by depletion of ll RNA smaller than 200nt (mirVana miRNA Purification Kit (Ambion) followed by two rounds of subtractive hybridization using Ribominus EukaryoteKit for RNA-seq (Invitrogen). To sequence 2',3'-cyclic phosphate cleavage products tRNA ligase was used to selectively ligate an RNA linker to all 2',3'-cyclic phosphatesin total RNA. (described in Schutz et al., 2010). Two biological repeats were performed for the following samples with different conditions and yeast strains: poly A+ mRNA sample and mRNA enriched (ribosome depletion). On replicate was performed for RNA 3' end mapping carrying a 2',3'-cyclic phosphate: 1 replicate
Project description:Sugarcane is a very efficient crop to produce ethanol. In recent years, extensive efforts have been made in order to increase sugarcane yields. To reach this goal, molecular biology tools have been used comprehensively, identifying genes, pathways and genetic polymorphisms. However, some important molecular components, like microRNAs, have not been deeply investigated. MicroRNAs are an important class of endogenous small, noncoding RNAs that regulate gene expression at the post-transcription level and play fundamental roles in diverse aspects of animal and plant biology. Plant genomes harbor numerous miRNA genes that regulate many protein-coding genes to influence key processes ranging from development, metabolism, and responses to abiotic and biotic stresses. There is wide range of pests and diseases that affect sugarcane, yet the mechanisms that regulate pathogen interactions with sugarcane have not been thoroughly investigated. To gain knowledge on the physiological responses to pathogens mediated by microRNAs in sugarcane, we screened the transcriptoma of sugarcane plants infected with Acidovorax avenae subsp avenae, the causal agent of red stripe disease in sugarcane, and detected several microRNAs modulated in the presence of the pathogen. Furthermore, we validated with qPCR a number of microRNA expression patterns observed by bioinformatics analysis. In addition, we observed high expression levels of several star microRNAs, in numbers larger than the mature microRNAs in some cases. Interestingly, sof-miR408 was consistently down-regulated in the presence of several pathogens, but not in the presence beneficial microbes. This result indicates that the sugarcane senses pathogenic or beneficial microorganisms differentially and triggers specific epigenetic regulatory mechanisms accordingly Screenning of sRNA transcriptome of sugarcane plants infected with Acidovorax avenae subsp avenae after seven days
Project description:Argonaute (AGO) proteins interact with distinct classes of small RNAs to direct multiple regulatory outcomes. In many organisms, including plants, fungi and nematodes, cellular RNAdependent RNA polymerases (RdRPs) utilize AGO targets as templates for amplification of silencing signals. Here, we show that distinct RdRPs function sequentially to produce small RNAs that target endogenous loci in C. elegans. We show that DCR-1, the RdRP RRF-3, and the dsRNA-binding protein RDE-4, are required for the biogenesis of 26nt RNAs, termed 26GRNAs, and that 26G-RNAs engage the Piwi-clade AGO, ERGO-1. Our findings support a model in which targeting by ERGO-1 recruits a second RdRP (RRF-1 or EGO-1), which in turn transcribes 22G-RNAs that interact with worm-specific AGOs (WAGOs) to direct gene silencing. ERGO-1 targets exhibit a non-random distribution in the genome and appear to include many gene duplications, suggesting that this pathway may control over-expression resulting from gene expansion. 8 samples examined. Small RNA libraries generated from: C. elegans animals.
Project description:High-throughput pyrosequencing of endogenous small RNAs from >95% male enriched populations of alg-3(tm1155);alg-4(ok1041);fog-2(q71) and fog-2(q71) worms as well as purified spermatids from fem-3(q20) adult worms. Gametogenesis is thermosensitive in numerous metazoa ranging from worms to man. In C. elegans a variety of germ-line nuage- (P-granule) -associated RNA-binding proteins including the Piwi-clade Argonaute, PRG-1, have been implicated in temperature-dependent fertility. Here, we describe the role of two AGO-class paralogs, alg-3 (T22B3.2) and alg-4 (ZK757.3) in promoting male fertility at elevated temperatures. A rescuing GFP::alg-3 transgene is localized in P-granules beginning at the late pachytene stage of male gametogenesis. alg-3/4 double mutants lack a subgroup of small RNAs, named 26G-RNAs, which target and appear to down-regulate numerous spermatogenesis-expressed mRNAs. These findings add to a growing number of AGO pathways required for temperature-dependent fertility in C. elegans and support a model in which AGOs and their small RNA co-factors function to promote robustness in gene-expression networks. 3 samples examined. Small RNAs from alg-3(tm1155);alg-4(ok1041);fog-2(q71) males and fog-2(q71) males. Small RNAs from spermatids isolated from ferm-3(q20) worms.