Decoding Human Cytomegalovirus
23 Nov 2012-Science (American Association for the Advancement of Science)-Vol. 338, Iss: 6110, pp 1088-1093
TL;DR: The results reveal an unanticipated complexity to the HCMV coding capacity and illustrate the role of regulated changes in transcript start sites in generating this complexity.
Abstract: The human cytomegalovirus (HCMV) genome was sequenced 20 years ago. However, like those of other complex viruses, our understanding of its protein coding potential is far from complete. We used ribosome profiling and transcript analysis to experimentally define the HCMV translation products and follow their temporal expression. We identified hundreds of previously unidentified open reading frames and confirmed a fraction by means of mass spectrometry. We found that regulated use of alternative transcript start sites plays a broad role in enabling tight temporal control of HCMV protein expression and allowing multiple distinct polypeptides to be generated from a single genomic locus. Our results reveal an unanticipated complexity to the HCMV coding capacity and illustrate the role of regulated changes in transcript start sites in generating this complexity.
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28 Jul 2005
TL;DR: PfPMP1）与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations
TL;DR: It is shown that N6-methyladenosine (m6A), a messenger RNA (mRNA) modification present on transcripts of pluripotency factors, drives this transition from the pluripotent to the differentiated state.
Abstract: Naive and primed pluripotent states retain distinct molecular properties, yet limited knowledge exists on how their state transitions are regulated. Here, we identify Mettl3, an N(6)-methyladenosine (m(6)A) transferase, as a regulator for terminating murine naive pluripotency. Mettl3 knockout preimplantation epiblasts and naive embryonic stem cells are depleted for m(6)A in mRNAs, yet are viable. However, they fail to adequately terminate their naive state and, subsequently, undergo aberrant and restricted lineage priming at the postimplantation stage, which leads to early embryonic lethality. m(6)A predominantly and directly reduces mRNA stability, including that of key naive pluripotency-promoting transcripts. This study highlights a critical role for an mRNA epigenetic modification in vivo and identifies regulatory modules that functionally influence naive and primed pluripotency in an opposing manner.
1,181 citations
TL;DR: This work presents a genome-wide approach, based on ribosome profiling, for measuring absolute protein synthesis rates, and reveals how general principles, important both for understanding natural systems and for synthesizing new ones, emerge from quantitative analyses of protein synthesis.
1,115 citations
01 Jun 2013
TL;DR: It is shown that classical noncoding RNAs and 5' UTRs show the same ribosomes occupancy as lincRNAs, demonstrating that ribosome occupancy alone is not sufficient to classify transcripts as coding or nonc coding.
Abstract: Large noncoding RNAs are emerging as an important component in cellular regulation. Considerable evidence indicates that these transcripts act directly as functional RNAs rather than through an encoded protein product. However, a recent study of ribosome occupancy reported that many large intergenic ncRNAs (lincRNAs) are bound by ribosomes, raising the possibility that they are translated into proteins. Here, we show that classical noncoding RNAs and 5′ UTRs show the same ribosome occupancy as lincRNAs, demonstrating that ribosome occupancy alone is not sufficient to classify transcripts as coding or noncoding. Instead, we define a metric based on the known property of translation whereby translating ribosomes are released upon encountering a bona fide stop codon. We show that this metric accurately discriminates between protein-coding transcripts and all classes of known noncoding transcripts, including lincRNAs. Taken together, these results argue that the large majority of lincRNAs do not function through encoded proteins.
606 citations
Cites methods from "Decoding Human Cytomegalovirus"
...…using labor-intensive approaches such as mass spectrometry and or epitope tagging that have been used to evaluate whether translation events observed in ribosome profiling experiments contribute to a cell’s proteome (Bánfai et al., 2012; Slavoff et al., 2013; Stern-Ginossar et al., 2012)....
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TL;DR: In this article, a metric based on the known property of translation whereby translating ribosomes are released upon encountering a bona fide stop codon was defined, which accurately discriminates between protein-coding transcripts and all classes of known noncoding RNAs, including lincRNAs.
591 citations
References
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TL;DR: A new method for determining nucleotide sequences in DNA is described, which makes use of the 2',3'-dideoxy and arabinon nucleoside analogues of the normal deoxynucleoside triphosphates, which act as specific chain-terminating inhibitors of DNA polymerase.
Abstract: A new method for determining nucleotide sequences in DNA is described. It is similar to the “plus and minus” method [Sanger, F. & Coulson, A. R. (1975) J. Mol. Biol. 94, 441-448] but makes use of the 2′,3′-dideoxy and arabinonucleoside analogues of the normal deoxynucleoside triphosphates, which act as specific chain-terminating inhibitors of DNA polymerase. The technique has been applied to the DNA of bacteriophage ϕX174 and is more rapid and more accurate than either the plus or the minus method.
62,728 citations
28 Jul 2005
TL;DR: PfPMP1）与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations
TL;DR: A novel peptide search engine using a probabilistic scoring model that can handle data with arbitrarily high fragment mass accuracy, is able to assign and score complex patterns of post-translational modifications, and accommodates extremely large databases.
Abstract: A key step in mass spectrometry (MS)-based proteomics is the identification of peptides in sequence databases by their fragmentation spectra. Here we describe Andromeda, a novel peptide search engine using a probabilistic scoring model. On proteome data, Andromeda performs as well as Mascot, a widely used commercial search engine, as judged by sensitivity and specificity analysis based on target decoy searches. Furthermore, it can handle data with arbitrarily high fragment mass accuracy, is able to assign and score complex patterns of post-translational modifications, such as highly phosphorylated peptides, and accommodates extremely large databases. The algorithms of Andromeda are provided. Andromeda can function independently or as an integrated search engine of the widely used MaxQuant computational proteomics platform and both are freely available at www.maxquant.org. The combination enables analysis of large data sets in a simple analysis workflow on a desktop computer. For searching individual spect...
4,689 citations
Book•
03 Oct 2000
TL;DR: IPCC Special Report on Emissions Scenarios as mentioned in this paper provides an overview of the scenario literature and the scenario driving forces, as well as a summary of the discussions and recommendations.
Abstract: IPCC Special Report on Emissions Scenarios Contents: Foreword Preface Summary for policymakers Technical Summary Chapter 1: Background and Overview Chapter 2: An Overview of the Scenario Literature Chapter 3: Scenario Driving Forces Chapter 4: An Overview of Scenarios Chapter 5: Emission Scenarios Chapter 6: Summary Discussions and Recommendations
3,304 citations
TL;DR: A suite of techniques, based on ribosome profiling, are presented to provide genome-wide maps of protein synthesis as well as a pulse-chase strategy for determining rates of translation elongation, revealing an unanticipated complexity to mammalian proteomes.
1,953 citations