keyword
MENU ▼
Read by QxMD icon Read
search

Posttranscriptional modification

keyword
https://www.readbyqxmd.com/read/28623126/crystal-structure-of-trna-his-guanylyltransferase-from-saccharomyces-cerevisiae
#1
Kitaik Lee, Eun Hye Lee, Jonghyeon Son, Kwang Yeon Hwang
tRNA maturation involves several steps, including processing, splicing, CCA addition, and posttranscriptional modifications. tRNA(His) guanylyltransferase (Thg1) is the only enzyme known to catalyze templated nucleotide addition in the 3'-5' direction, unlike other DNA and RNA polymerases. For a better understanding of its unique catalytic mechanism at the molecular level, we determined the crystal structure of GTP-bound Thg1 from Saccharomyces cerevisiae at the maximum resolution of 3.0 Å. The structure revealed the enzyme to have a tetrameric conformation that is well conserved among different species, and the GTP molecule was clearly bound at the active site, coordinating with two magnesium ions...
June 13, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28601222/synthesis-function-and-heterogeneity-of-snorna-guided-posttranscriptional-nucleoside-modifications-in-eukaryotic-ribosomal-rnas
#2
Anthony K Henras, Célia Plisson-Chastang, Odile Humbert, Yves Romeo, Yves Henry
Ribosomal RNAs contain numerous 2'-O-methylated nucleosides and pseudouridines. Methylation of the 2' oxygen of ribose moieties and isomerization of uridines into pseudouridines are catalyzed by C/D and H/ACA small nucleolar ribonucleoprotein particles, respectively. We review the composition, structure, and mode of action of archaeal and eukaryotic C/D and H/ACA particles. Most rRNA modifications cluster in functionally crucial regions of the rRNAs, suggesting they play important roles in translation. Some of these modifications promote global translation efficiency or modulate translation fidelity...
2017: Enzymes
https://www.readbyqxmd.com/read/28601221/posttranscriptional-rna-pseudouridylation
#3
Meemanage D De Zoysa, Yi-Tao Yu
Pseudouridine (Ψ) is the most abundant posttranscriptional modification in noncoding RNAs. Pseudouridines are often clustered in important regions of rRNAs (ribosomal RNAs), snRNAs (small nuclear RNAs), and tRNAs (transfer RNAs), contributing to RNA function. Pseudouridylation is governed by two independent mechanisms. The first involves single protein enzymes called pseudouridine synthases (PUSs) that alone recognize the substrate and catalyze the isomerization of uridine to pseudouridine (RNA-independent pseudouridylation)...
2017: Enzymes
https://www.readbyqxmd.com/read/28601219/the-importance-of-being-modified-the-role-of-rna-modifications-in-translational-fidelity
#4
Paul F Agris, Amithi Narendran, Kathryn Sarachan, Ville Y P Väre, Emily Eruysal
The posttranscriptional modifications of tRNA's anticodon stem and loop (ASL) domain represent a third level, a third code, to the accuracy and efficiency of translating mRNA codons into the correct amino acid sequence of proteins. Modifications of tRNA's ASL domain are enzymatically synthesized and site specifically located at the anticodon wobble position-34 and 3'-adjacent to the anticodon at position-37. Degeneracy of the 64 Universal Genetic Codes and the limitation in the number of tRNA species require some tRNAs to decode more than one codon...
2017: Enzymes
https://www.readbyqxmd.com/read/28576825/identification-of-an-optimized-2-o-methylated-tri-nucleotide-rna-motif-inhibiting-toll-like-receptor-7-and-8
#5
Felix C F Schmitt, Isabel Freund, Markus A Weigand, Mark Helm, Alexander H Dalpke, Tatjana Eigenbrod
Bacterial RNA serves an important function as activator of the innate immune system. In humans bacterial RNA is sensed by the endosomal receptors TLR7 and TLR8. Differences in the posttranscriptional modification profile of prokaryotic as compared to eukaryotic RNA allow innate immune cells to discriminate between 'host' and 'foreign' RNA. Ribose 2'-O-methylation is of particular importance and has been reported to antagonize TLR7/8 activation. Yet, the exact sequence context in which 2'-O-methylation has to occur to mediate its inhibitory activity remains largely undefined...
June 2, 2017: RNA
https://www.readbyqxmd.com/read/28567652/pull-down-assay-to-characterize-ca-2-calmodulin-binding-to-plant-receptor-kinases
#6
Christine Kaufmann, Margret Sauter
Plant receptor-like kinases (RLKs) are regulated by posttranscriptional modification and by interaction with regulatory proteins. A common modification of RLKs is (auto)phosphorylation, and a common regulatory protein is the calcium sensor calmodulin (CaM). We have developed protocols to detect the interaction of an RLK with CaM. The interaction with CaM was shown by bimolecular fluorescence complementation (BiFC) (see Chapter 14) and pull-down assay (this chapter). Both methods offer unique advantages. BiFC is useful in showing interaction of soluble as well as of membrane-bound proteins in planta...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28567651/bifc-assay-to-detect-calmodulin-binding-to-plant-receptor-kinases
#7
Cornelia Fischer, Margret Sauter, Petra Dietrich
Plant receptor-like kinases (RLKs) are regulated at various levels including posttranscriptional modification and interaction with regulatory proteins. Calmodulin (CaM) is a calcium-sensing protein that was shown to bind to some RLKs such as the PHYTOSULFOKINE RECEPTOR1 (PSKR1). The CaM-binding site is embedded in subdomain VIa of the kinase domain. It is possible that many more of RLKs interact with CaM than previously described. To unequivocally confirm CaM binding, several methods exist. Bimolecular fluorescence complementation (BiFC) and pull-down assays have been successfully used to study CaM binding to PSKR1 and are described in this chapter (BiFC) and in Chapter 15 (pull down)...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28549193/label-free-direct-localization-and-relative-quantitation-of-the-rna-nucleobase-methylations-m6a-m5c-m3u-and-m5u-by-top-down-mass-spectrometry
#8
Heidelinde Glasner, Christian Riml, Ronald Micura, Kathrin Breuker
Nucleobase methylations are ubiquitous posttranscriptional modifications of ribonucleic acids (RNA) that can substantially increase the structural diversity of RNA in a highly dynamic fashion with implications for gene expression and human disease. However, high throughput, deep sequencing does not generally provide information on posttranscriptional modifications (PTMs). A promising alternative approach for the characterization of PTMs, i.e. their identification, localization, and relative quantitation, is top-down mass spectrometry (MS)...
May 26, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28546713/current-concepts-of-epigenetics-in-testicular-cancer
#9
REVIEW
Alfredo Harb-De la Rosa, Meenakkshy Manoharan, Ahmed Saeed Goolam
Testicular germ cell tumors (GCTs) are characterized into seminomas (SGCTs) and non-seminomatous testicular germ cell tumors (NSGCTs). Serum tumor markers (STMs) play an important role in testicular cancer as they provide useful information for diagnosis, staging, and detection of recurrence. Nonetheless, additional tumor markers for early diagnosis and therapeutic options are required to enhance specificity of serological diagnosis of testes cancers. Epigenetics is defined as inherited changes in gene expression that are not encoded in the DNA structure...
June 2017: Indian Journal of Surgical Oncology
https://www.readbyqxmd.com/read/28521327/epigenomics-pharmacoepigenomics-and-personalized-medicine-in-cervical-cancer
#10
Shama Prasada Kabekkodu, Sanjiban Chakrabarty, Supriti Ghosh, Angela Brand, Kapaettu Satyamoorthy
Epigenomics encompasses the study of genome-wide changes in DNA methylation, histone modifications and noncoding RNAs leading to altered transcription, chromatin structure, and posttranscription RNA processing, respectively, resulting in an altered rate of gene expression. The role of epigenetic modifications facilitating human diseases is well established. Previous studies have identified histone and cytosine code during normal and pathological conditions with special emphasis on how these modifications regulate transcriptional events...
May 19, 2017: Public Health Genomics
https://www.readbyqxmd.com/read/28484874/effects-of-arsenic-toxicity-beyond-epigenetic-modifications
#11
REVIEW
Geir Bjørklund, Jan Aaseth, Salvatore Chirumbolo, Mauricio A Urbina, Riaz Uddin
Worldwide chronic arsenic (As) poisoning by arsenic-contaminated groundwater is one of the most threatening public health problems. Chronic inorganic As (inAs) exposure has been associated with various forms of cancers and numerous other pathological effects in humans, collectively known as arsenicosis. Over the past decade, evidence indicated that As-induced epigenetic modifications have a role in the adverse effects on human health. The main objective of this article is to review the evidence on epigenetic modifications induced by arsenicals...
May 8, 2017: Environmental Geochemistry and Health
https://www.readbyqxmd.com/read/28484591/brothers-in-arms-emerging-roles-of-rna-epigenetics-in-dna-damage-repair
#12
Jinwei Zhang
N6-methyladenosine (m(6)A) is a widespread posttranscriptional RNA modification that occurs in tRNA, rRNA, snRNA, viral RNAs, and more recently is shown to occur in mRNA in a dynamic, reversible manner. At the epicenter of RNA epigenetics, m(6)A influences essentially all stages of RNA metabolism. As a result, m(6)A modulates cell differentiation and pluripotency, cell cycle and tumorigenesis, and several types of stress responses, etc. A recent report by Shi and colleagues uncovers a novel pathway in which m(6)A RNA, its associated enzymes, and DNA polymerase κ constitute an early-response system that confers cellular resistance to ultraviolet irradiation, separate from the canonical nucleotide excision repair (NER) pathway that normally repairs UV-induced DNA damage...
2017: Cell & Bioscience
https://www.readbyqxmd.com/read/28441146/epigenetic-regulation-of-glucose-metabolism
#13
Sapna Sharma, Jennifer Kriebel, Harald Grallert
PURPOSE OF REVIEW: Glucose metabolism is a central process in mammalian energy homeostasis. Its deregulation is a key factor in development of metabolic disease like diabetes and cancer. In recent decades, our understanding of gene regulation at the signaling, chromatin and posttranscriptional levels has seen dramatic developments. RECENT FINDINGS: A number of epigenetic mechanisms that do not affect the genetic code can be assessed with new technologies. However, increasing complexity becomes a major challenge for translation into clinical application...
July 2017: Current Opinion in Clinical Nutrition and Metabolic Care
https://www.readbyqxmd.com/read/28439027/biochemical-and-structural-characterization-of-oxygen-sensitive-2-thiouridine-synthesis-catalyzed-by-an-iron-sulfur-protein-ttua
#14
Minghao Chen, Shin-Ichi Asai, Shun Narai, Shusuke Nambu, Naoki Omura, Yuriko Sakaguchi, Tsutomu Suzuki, Masao Ikeda-Saito, Kimitsuna Watanabe, Min Yao, Naoki Shigi, Yoshikazu Tanaka
Two-thiouridine (s(2)U) at position 54 of transfer RNA (tRNA) is a posttranscriptional modification that enables thermophilic bacteria to survive in high-temperature environments. s(2)U is produced by the combined action of two proteins, 2-thiouridine synthetase TtuA and 2-thiouridine synthesis sulfur carrier protein TtuB, which act as a sulfur (S) transfer enzyme and a ubiquitin-like S donor, respectively. Despite the accumulation of biochemical data in vivo, the enzymatic activity by TtuA/TtuB has rarely been observed in vitro, which has hindered examination of the molecular mechanism of S transfer...
May 9, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28435892/dramatic-improvement-of-crispr-cas9-editing-in-candida-albicans-by-increased-single-guide-rna-expression
#15
Henry Ng, Neta Dean
The clustered regularly interspaced short palindromic repeat system with CRISPR-associated protein 9 nuclease (CRISPR/Cas9) has emerged as a versatile tool for genome editing in Candida albicans. Mounting evidence from other model systems suggests that the intracellular levels of single guide RNA (sgRNA) limit the efficiency of Cas9-dependent DNA cleavage. Here, we tested this idea and describe a new means of sgRNA delivery that improves previously described methods by ~10-fold. The efficiency of Cas9/sgRNA-dependent cleavage and repair of a single-copy yeast enhanced monomeric red fluorescent protein (RFP) gene was measured as a function of various parameters that are hypothesized to affect sgRNA accumulation, including transcriptional and posttranscriptional processing...
March 2017: MSphere
https://www.readbyqxmd.com/read/28432181/dual-nature-of-pseudouridylation-in-u2-snrna-pus1p-dependent-and-pus1p-independent-activities-in-yeasts-and-higher-eukaryotes
#16
Svetlana Deryusheva, Joseph G Gall
The pseudouridine at position 43 in vertebrate U2 snRNA is one of the most conserved posttranscriptional modifications of spliceosomal snRNAs; the equivalent position is pseudouridylated in U2 snRNAs in different phyla including fungi, insects, and worms. Pseudouridine synthase Pus1p acts alone on U2 snRNA to form this pseudouridine in yeast Saccharomyces cerevisiae and mouse. Furthermore, in S. cerevisiae Pus1p is the only pseudouridine synthase for this position. Using an in vivo yeast cell system we tested enzymatic activity of Pus1p from the fission yeast Schizosaccharomyces pombe, the worm Caenorhabditis elegans, the fruit fly Drosophila melanogaster and the frog Xenopus tropicalis...
April 21, 2017: RNA
https://www.readbyqxmd.com/read/28401060/therapeutic-targeting-of-histone-modifications-in-adult-and-pediatric-high-grade-glioma
#17
REVIEW
Maria J Williams, Will G B Singleton, Stephen P Lowis, Karim Malik, Kathreena M Kurian
Recent exciting work partly through The Cancer Genome Atlas has implicated epigenetic mechanisms including histone modifications in the development of both pediatric and adult high-grade glioma (HGG). Histone lysine methylation has emerged as an important player in regulating gene expression and chromatin function. Lysine (K) 27 (K27) is a critical residue in all seven histone 3 variants and the subject of posttranslational histone modifications, as it can be both methylated and acetylated. In pediatric HGG, two critical single-point mutations occur in the H3F3A gene encoding the regulatory histone variant H3...
2017: Frontiers in Oncology
https://www.readbyqxmd.com/read/28392787/bioconjugation-of-small-molecules-to-rna-impedes-its-recognition-by-toll-like-receptor-7
#18
Isabell Hellmuth, Isabel Freund, Janine Schlöder, Salifu Seidu-Larry, Kathrin Thüring, Kaouthar Slama, Jens Langhanki, Stefka Kaloyanova, Tatjana Eigenbrod, Matthias Krumb, Sandra Röhm, Kalina Peneva, Till Opatz, Helmut Jonuleit, Alexander H Dalpke, Mark Helm
A fundamental mechanism of the innate immune system is the recognition, via extra- and intracellular pattern-recognition receptors, of pathogen-associated molecular patterns. A prominent example is represented by foreign nucleic acids, triggering the activation of several signaling pathways. Among these, the endosomal toll-like receptor 7 (TLR7) is known to be activated by single-stranded RNA (ssRNA), which can be specifically influenced through elements of sequence structure and posttranscriptional modifications...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28353398/a-fly-view-on-the-roles-and-mechanisms-of-the-m-6-a-mrna-modification-and-its-players
#19
Tina Lence, Matthias Soller, Jean-Yves Roignant
RNA modifications are an emerging layer of posttranscriptional gene regulation in eukaryotes. N(6)-methyladenosine (m(6)A) is among the most abundant modifications in mRNAs (mRNAs) that was shown to influence many physiological processes from yeast to mammals. Like DNA methylation, m(6)A in mRNA is dynamically regulated. A conserved methyltransferase complex catalyzes the deposition of the methyl group on adenosine, which can be removed by specific classes of demethylases. Furthermore, YTH-domain containing proteins can recognize this modification to mediate m(6)A-dependent activities...
March 29, 2017: RNA Biology
https://www.readbyqxmd.com/read/28349465/transcriptome-wide-mapping-of-n-1-methyladenosine-methylome
#20
Xiaoyu Li, Jinying Peng, Chengqi Yi
N (1)-Methyladenosine (m(1)A) is a prevalent posttranscriptional RNA modification and commonly found in tRNA and rRNA. Very recent works have also demonstrated the prevalence of m(1)A in mammalian mRNA. Hence, high-throughput methods that allow transcriptome-wide mapping of m(1)A will be important for further functional investigations. Here, we describe a technique called "m(1)A-ID-Seq", which is based on m(1)A immunoprecipitation and the inherent ability of m(1)A to stall reverse transcription, to map m(1)A in the transcriptome...
2017: Methods in Molecular Biology
keyword
keyword
93507
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"