Meiosis: MeiRNA hits the spot. (1/21477)

The protein Mei2 performs at least two functions required in fission yeast for the switch from mitotic to meiotic cell cycles. One of these functions also requires meiRNA. It appears that meiRNA targets Mei2 to the nucleus, where it can promote the first meiotic division.  (+info)

Telomerase reverse transcriptase gene is a direct target of c-Myc but is not functionally equivalent in cellular transformation. (2/21477)

The telomerase reverse transcriptase component (TERT) is not expressed in most primary somatic human cells and tissues, but is upregulated in the majority of immortalized cell lines and tumors. Here, we identify the c-Myc transcription factor as a direct mediator of telomerase activation in primary human fibroblasts through its ability to specifically induce TERT gene expression. Through the use of a hormone inducible form of c-Myc (c-Myc-ER), we demonstrate that Myc-induced activation of the hTERT promoter requires an evolutionarily conserved E-box and that c-Myc-ER-induced accumulation of hTERT mRNA takes place in the absence of de novo protein synthesis. These findings demonstrate that the TERT gene is a direct transcriptional target of c-Myc. Since telomerase activation frequently correlates with immortalization and telomerase functions to stabilize telomers in cycling cells, we tested whether Myc-induced activation of TERT gene expression represents an important mechanism through which c-Myc acts to immortalize cells. Employing the rat embryo fibroblast cooperation assay, we show that TERT is unable to substitute for c-Myc in the transformation of primary rodent fibroblasts, suggesting that the transforming activities of Myc extend beyond its ability to activate TERT gene expression and hence telomerase activity.  (+info)

Tight binding of the 5' exon to domain I of a group II self-splicing intron requires completion of the intron active site. (3/21477)

Group II self-splicing requires the 5' exon to form base pairs with two stretches of intronic sequence (EBS1 and EBS2) which also bind the DNA target during retrotransposition of the intron. We have used dimethyl sulfate modification of bases to obtain footprints of the 5' exon on intron Pl.LSU/2 from the mitochondrion of the alga Pylaiella littoralis, as well as on truncated intron derivatives. Aside from the EBS sites, which are part of the same subdomain (ID) of ribozyme secondary structure, three distant adenines become either less or more sensitive to modification in the presence of the exon. Unexpectedly, one of these adenines in subdomain IC1 is footprinted only in the presence of the distal helix of domain V, which is involved in catalysis. While the loss of that footprint is accompanied by a 100-fold decrease in the affinity for the exon, both protection from modification and efficient binding can be restored by a separate domain V transcript, whose binding results in its own, concise footprint on domains I and III. Possible biological implications of the need for the group II active site to be complete in order to observe high-affinity binding of the 5' exon to domain I are discussed.  (+info)

Telomerase activity is sufficient to allow transformed cells to escape from crisis. (4/21477)

The introduction of simian virus 40 large T antigen (SVLT) into human primary cells enables them to proliferate beyond their normal replicative life span. In most cases, this temporary escape from senescence eventually ends in a second proliferative block known as "crisis," during which the cells cease growing or die. Rare immortalization events in which cells escape crisis are frequently correlated with the presence of telomerase activity. We tested the hypothesis that telomerase activation is the critical step in the immortalization process by studying the effects of telomerase activity in two mortal SVLT-Rasval12-transformed human pancreatic cell lines, TRM-6 and betalox5. The telomerase catalytic subunit, hTRT, was introduced into late-passage cells via retroviral gene transfer. Telomerase activity was successfully induced in infected cells, as demonstrated by a telomerase repeat amplification protocol assay. In each of nine independent infections, telomerase-positive cells formed rapidly dividing cell lines while control cells entered crisis. Telomere lengths initially increased, but telomeres were then maintained at their new lengths for at least 20 population doublings. These results demonstrate that telomerase activity is sufficient to enable transformed cells to escape crisis and that telomere elongation in these cells occurs in a tightly regulated manner.  (+info)

The influence of junction conformation on RNA cleavage by the hairpin ribozyme in its natural junction form. (5/21477)

In the natural form of the hairpin ribozyme the two loop-carrying duplexes that comprise the majority of essential bases for activity form two adjacent helical arms of a four-way RNA junction. In the present work we have manipulated the sequence around the junction in a way known to perturb the global folding properties. We find that replacement of the junction by a different sequence that has the same conformational properties as the natural sequence gives closely similar reaction rate and Arrhenius activation energy for the substrate cleavage reaction. By comparison, rotation of the natural sequence in order to alter the three-dimensional folding of the ribozyme leads to a tenfold reduction in the kinetics of cleavage. Replacement with the U1 four-way junction that is resistant to rotation into the antiparallel structure required to allow interaction between the loops also gives a tenfold reduction in cleavage rate. The results indicate that the conformation of the junction has a major influence on the catalytic activity of the ribozyme. The results are all consistent with a role for the junction in the provision of a framework by which the loops are presented for interaction in order to create the active form of the ribozyme.  (+info)

Molecular dynamics studies of U1A-RNA complexes. (6/21477)

The U1A protein binds to a hairpin RNA and an internal-loop RNA with picomolar affinities. To probe the molecular basis of U1A binding, we performed state-of-the-art nanosecond molecular dynamics simulations on both complexes. The good agreement with experimental structures supports the protocols used in the simulations. We compare the dynamics, hydrogen-bonding occupancies, and interfacial flexibility of both complexes and also describe a rigid-body motion in the U1A-internal loop complex that is not observed in the U1A-hairpin simulation. We relate these observations to experimental mutational studies and highlight their significance in U1A binding affinity and specificity.  (+info)

A novel nucleotide incorporation activity implicated in the editing of mitochondrial transfer RNAs in Acanthamoeba castellanii. (7/21477)

In Acanthamoeba castellanii, most of the mtDNA-encoded tRNAs are edited by a process that replaces one or more of the first three nucleotides at their 5' ends. As a result, base pairing potential is restored at acceptor stem positions (1:72, 2:71, and/or 3:70, in standard tRNA nomenclature) that are mismatched according to the corresponding tRNA gene sequence. Here we describe a novel nucleotide incorporation activity, partially purified from A. castellanii mitochondria, that has properties implicating it in mitochondrial tRNA editing in this organism. This activity is able to replace nucleotides at the first three positions of a tRNA (positions 1, 2, and 3), matching the newly incorporated residues through canonical base pairing to the respective partner nucleotide in the 3' half of the acceptor stem. Labeling experiments with natural (Escherichia coli tRNATyr) and synthetic (run-off transcripts corresponding to A. castellanii mitochondrial tRNALeu1) substrates suggest that the nucleotide incorporation activity consists of at least two components, a 5' exonuclease or endonuclease and a template-directed 3'-to-5' nucleotidyltransferase. The nucleotidyltransferase component displays an ATP requirement and generates 5' pppN... termini in vitro. The development of an accurate and efficient in vitro system opens the way for detailed studies of the biochemical properties of this novel activity and its relationship to mitochondrial tRNA editing in A. castellanii. In addition, the system will allow delineation of the structural features in a tRNA that identify it as a substrate for the labeling activity.  (+info)

Photocrosslinking of 4-thio uracil-containing RNAs supports a side-by-side arrangement of domains 5 and 6 of a group II intron. (8/21477)

Previous studies suggested that domains 5 and 6 (D5 and D6) of group II introns act together in splicing and that the two helical structures probably do not interact by helix stacking. Here, we characterized the major Mg2+ ion- and salt-dependent, long-wave UV light-induced, intramolecular crosslinks formed in 4-thiouridine-containing D56 RNA from intron 5gamma (aI5gamma) of the COXI gene of yeast mtDNA. Four major crosslinks were mapped and found to result from covalent bonds between nucleotides separating D5 from D6 [called J(56)] and residues of D6 near and including the branch nucleotide. These findings are extended by results of similar experiments using 4-thioU containing D56 RNAs from a mutant allele of aI5gamma and from the group IIA intron, aI1. Trans-splicing experiments show that the crosslinked wild-type aI5gamma D56 RNAs are active for both splicing reactions, including some first-step branching. An RNA containing the 3-nt J(56) sequence and D6 of aI5gamma yields one main crosslink that is identical to the most minor of the crosslinks obtained with D56 RNA, but in this case in a cation-independent fashion. We conclude that the interaction between J(56) and D6 is influenced by charge repulsion between the D5 and D6 helix backbones and that high concentrations of cations allow the helices to approach closely under self-splicing conditions. The interaction between J(56) and D6 appears to be a significant factor establishing a side-by-side (i.e., not stacked) orientation of the helices of the two domains.  (+info)

Also, RNA-dependent RNA polymerase is part of the RNA interference pathway in many organisms. Messenger RNA (mRNA) is the RNA ... According to the length of RNA chain, RNA includes small RNA and long RNA. Usually, small RNAs are shorter than 200 nt in ... Biology portal Biomolecular structure RNA virus DNA History of RNA Biology List of RNA Biologists RNA Society Macromolecule RNA ... RNA can also be methylated. Like DNA, RNA can carry genetic information. RNA viruses have genomes composed of RNA that encodes ...
Page for SraJ RNA at Rfam v t e (Articles with short description, Short description matches Wikidata, Non-coding RNA, All stub ... "Targeted decay of a regulatory small RNA by an adaptor protein for RNase E and counteraction by an anti-adaptor RNA". Genes & ... GlmZ (formally known as SraJ) is a small non-coding RNA (ncRNA). It is the functional product of a gene which is not translated ... 2001). "Novel small RNA-encoding genes in the intergenic regions of Escherichia coli". Curr. Biol. 11 (12): 941-950. doi: ...
Diribarne G, Bensaude O (2009). "7SK RNA, a non-coding RNA regulating P-TEFb, a general transcription factor". RNA Biology. 6 ( ... 2): 122-8. doi:10.4161/rna.6.2.8115. PMID 19246988. Peterlin BM, Brogie JE, Price DH (2012). "7SK snRNA: a noncoding RNA that ... Yang Z, Zhu Q, Luo K, Zhou Q (November 2001). "The 7SK small nuclear RNA inhibits the CDK9/cyclin T1 kinase to control ... This release leads to a conformational change in 7SK RNA and the ejection of HEXIM. hnRNPs stabilize the complex lacking P-TEFb ...
RNA is usually responsible for making protein. The process of making RNA from DNA is called transcription. RNA uses a similar ... transcription of DNA into RNA and translation of RNA into protein. After DNA is transcribed into RNA, the molecule is known as ... CRAC integrates genomic locations and local coverage to enable splice junction or fusion RNA predictions directly from RNA-seq ... end of the RNA, generating a functional messenger RNA. This system allows the use of operons - collections of protein-coding ...
In addition to mRNA transcripts, RNA-Seq can look at different populations of RNA to include total RNA, small RNA, such as ... The cellular RNA is selected based on the desired size range. For small RNA targets, such as miRNA, the RNA is isolated through ... Total sample RNA output: Because the same amount of RNA is extracted from each sample, samples with more total RNA will have ... RNA selection/depletion: To analyze signals of interest, the isolated RNA can either be kept as is, filtered for RNA with 3' ...
Although RNA is fragile, some ancient RNAs may have evolved the ability to methylate other RNAs to protect them. If the RNA ... The RNA world hypothesis places RNA at center-stage when life originated. The RNA world hypothesis is supported by the ... doi:10.1261/rna.548807. PMC 1894930. PMID 17586759. Horning DP, Joyce GF (August 2016). "Amplification of RNA by an RNA ... Atkins JF, Gesteland RF, Cech T (2006). The RNA world: the nature of modern RNA suggests a prebiotic RNA world. Plainview, N.Y ...
... is the leading peer-reviewed scientific journal in the field of ribonucleic acid (RNA) research. It is indexed for ... "RNA Biology". 2018 Journal Citation Reports. Web of Science (Science ed.). Thomson Reuters. 2018. Official website (Use dmy ... This initiative is a collaboration between the journal and the consortium that produces the Rfam database of RNA families. The ... of families of RNA molecules in December 2008 and requires contributing authors to also submit a draft article on the RNA ...
The bacterial sroH RNA is a non-coding RNA that is 160 nucleotides in length. The function of this family is unknown. An SroH ... Page for sroH RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... Hobbs EC, Astarita JL, Storz G (January 2010). "Small RNAs and small proteins involved in resistance to cell envelope stress ...
... is a non-coding RNA that is antisense to the RNA-IN non-coding RNA. Transposition of insertion sequence IS10 is ... RNA-OUT consists of a stem-loop domain topped by a flexibly paired loop; the 5′ end of the target molecule, RNA-IN, is ... Page for RNA-OUT at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... end of the target RNA and a loop in the anti-sense RNA". Journal of Molecular Biology. 210 (3): 561-572. doi:10.1016/0022-2836( ...
The PrrF RNAs are analogs of the RyhB RNA, which is encoded by enteric bacteria. Expression of the PrrF RNAs is repressed by ... Page for PrrF RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... The PrrF RNAs are small non-coding RNAs involved in iron homeostasis and are encoded by all Pseudomonas species. ... HrrF RNA NrrF RNA Aggregatibacter iron-regulated sRNA Wilderman PJ, Sowa NA, FitzGerald DJ, FitzGerald PC, Gottesman S, Ochsner ...
This small RNA was shown to be bound by the Hfq protein. This RNA has been renamed as CyaR for (cyclic AMP-activated RNA). It ... The CyaR RNA (formerly known as RyeE RNA) non-coding RNA was identified in a large scale screen of Escherichia coli and was ... RydB RNA RyhB RNA RyeB RNA Wassarman, KM; Repoila F; Rosenow C; Storz G; Gottesman S (2001). "Identification of novel small ... Page for RyeE RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ...
The gcvB RNA gene encodes a small non-coding RNA involved in the regulation of a number of amino acid transport systems as well ... Transcription of the GcvB RNA is activated by the adjacent GcvA gene and repressed by the GcvR gene. A deletion of GcvB RNA ... Busi F, Le Derout J, Cerciat M, Régnier P, Hajnsdorf E (July 2010). "Is the secondary putative RNA-RNA interaction site ... Similar results were recently shown for the DsrA RNA. The physiological relevance of polymerisation is not known. The GcvB RNA ...
Cyanobacterial RNA thermometers Intergenic RNA thermometer Neisseria RNA thermometers Lig RNA thermometer Narberhaus F, ... An RNA thermometer (or RNA thermosensor) is a temperature-sensitive non-coding RNA molecule which regulates gene expression. ... Atkins JF, Gesteland RF, Cech T (2006). The RNA world: the nature of modern RNA suggests a prebiotic RNA world. Plainview, N.Y ... RNA Biology. 7 (1): 84-89. doi:10.4161/rna.7.1.10501. PMID 20009504. Breaker RR (January 2010). "RNA switches out in the cold ...
Page for sroD RNA at Rfam v t e (Articles with short description, Short description matches Wikidata, Non-coding RNA, All stub ... The bacterial sroD RNA gene is a non-coding RNA of 90 nucleotides in length. sroD is found in several Enterobacterial species ...
I. Structures of sar RNA and its target, ant mRNA". RNA. 3 (2): 141-156. PMC 1369469. PMID 9042942. Page for sar RNA at Rfam v ... Sar RNA is an antisense non-coding RNA that is partly responsible for the negative regulation of antirepressor synthesis during ... Structurally, Sar RNA forms two stem-loops. Schaefer KL, McClure WR (February 1997). "Antisense RNA control of gene expression ... The target of Sar RNA is ant mRNA. ... t e (GO template errors, Antisense RNA, All stub articles, ...
C0299 RNA C0343 RNA C0465 RNA Tjaden B, Saxena RM, Stolyar S, Haynor DR, Kolker E, Rosenow C (2002). "Transcriptome analysis of ... The C0719 RNA is a bacterial non-coding RNA of 222 nucleotides in length that is found between the yghK and glcB genes in the ... Page for C0719 RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... This non-coding RNA was originally identified in E.coli using high-density oligonucleotide probe arrays (microarray.) The ...
Page for sroE RNA at Rfam v t e (Articles with short description, Short description matches Wikidata, Non-coding RNA, All stub ... The bacterial sroE RNA gene is a non-coding RNA molecule of 90 nucleotides in length. sroE is found in several Enterobacterial ...
The SL1 RNA is involved in trans-splicing, which is a form of RNA processing. The acquisition of a spliced leader from an SL ... Page for SL1 RNA at Rfam v t e (GO template errors, Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... This family represents the SL1 RNA. The gene encoding SL1 RNA is commonly, but not always, located in the spacer region between ... Dassanayake RS, Chandrasekharan NV, Karunanayake EH (May 2001). "Trans-spliced leader RNA, 5S-rRNA genes and novel variant ...
RyfA RNA RydB RNA RydC RNA MicA RNA Wassarman, KM; Repoila F; Rosenow C; Storz G; Gottesman S (2001). "Identification of novel ... Page for RybB RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... RybB is a small non-coding RNA was identified in a large scale screen of Escherichia coli. The function of this short RNA has ... Desnoyers G, Massé E (2012). "Noncanonical repression of translation initiation through small RNA recruitment of the RNA ...
The GlmY RNA (formally known as tke1) family consists of a number of bacterial RNA genes of around 167 bases in length. The ... Page for tke1 RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... "Targeted decay of a regulatory small RNA by an adaptor protein for RNase E and counteraction by an anti-adaptor RNA". Genes & ... Reichenbach B, Maes A, Kalamorz F, Hajnsdorf E, Görke B (2008). "The small RNA GlmY acts upstream of the sRNA GlmZ in the ...
... is the nanoscale folding of RNA, enabling the RNA to create particular shapes to organize these molecules. It is a ... RNA origami is synthesized by enzymes that fold RNA into particular shapes. The folding of the RNA occurs in living cells under ... RNA origami is represented as a DNA gene, which within cells can be transcribed into RNA by RNA polymerase. Many computer ... Once encoded as a synthetic DNA gene, adding RNA polymerase resulted in the formation of RNA origami. Observation of RNA was ...
RNA pol II) binding and non-coding RNA transcription. The level of RNA pol II-enhancer interaction and RNA transcript formation ... Enhancer RNAs (eRNAs) represent a class of relatively long non-coding RNA molecules (50-2000 nucleotides) transcribed from the ... As a result, polyA+ 1D-eRNAs may represent a mixed group of true enhancer-templated RNAs and multiexonic RNAs. Bidirectional ... RNA-seq) and chromatin immunoprecipitation-sequencing (ChIP-seq). RNA-seq permits the direct identification of eRNAs by ...
The RtT RNA (repeat structure of the tyrT operon) is a RNA element that is released from the tyrT operon of Escherichia coli. ... Page for RtT RNA at Rfam v t e (Cis-regulatory RNA elements, All stub articles, Molecular and cellular biology stubs). ... which lacks RtT RNA and has an alternate starvation response. Bösl M, Kersten H (November 1991). "A novel RNA product of the ...
Ahlquist P (May 2002). "RNA-dependent RNA polymerases, viruses, and RNA silencing". Science. 296 (5571): 1270-3. Bibcode: ... "Double-stranded RNA binding may be a general plant RNA viral strategy to suppress RNA silencing". Journal of Virology. 80 (12 ... RNAi is an RNA-dependent gene silencing process that is controlled by RISC and is initiated by short double-stranded RNA ... RNA interference (RNAi) is a biological process in which RNA molecules are involved in sequence-specific suppression of gene ...
... is a small non-coding RNA found in Vibrio cholerae and related bacteria. MtlS is found in the mannitol operon, which ... Page for MtlS RNA at Rfam v t e (Orphaned articles from November 2017, All orphaned articles, Non-coding RNA, All stub articles ... The MtlS RNA is expressed when the bacteria are grown on carbon sources other than mannitol. MtlS is responsible for the post- ... "The Vibrio cholerae Mannitol Transporter is Regulated Posttranscriptionally by the MtlS Small Regulatory RNA". Journal of ...
In enzymology, a RNA uridylyltransferase (EC 2.7.7.52) is an enzyme that catalyzes the chemical reaction UTP + RNAn ⇌ {\ ... end of an RNA primer". Nucleic Acids Research. 9 (11): 2433-53. doi:10.1093/nar/9.11.2433. PMC 326863. PMID 6269049. Portal: ... RNA uridylyltransferase. Other names in common use include terminal uridylyltransferase, and TUT. As of late 2007, 8 structures ...
indica). αr45C RNA species are 147-153 nt long (Table 1) and share a well defined common secondary structure (Figure 1). All of ... αr45 is a family of bacterial small non-coding RNAs with representatives in a broad group of α-proteobacteria from the order ... Will S, Reiche K, Hofacker IL, Stadler PF, Backofen R (2007). "Inferring Noncoding RNA Families and Classes by Means of Genome- ... Recent deep sequencing-based characterization of the small RNA fraction (50-350 nt) of S. meliloti 2011 further confirmed the ...
This RNA was identified in a computational screen of E. coli. The function of this RNA is unknown. IS061 RNA IS128 RNA Tjaden B ... The IS102 RNA is a non-coding RNA that is found in bacteria such as Shigella flexneri and Escherichia coli. The RNA is 208 ... Page for IS102 RNA at Rfam v t e (Articles with short description, Short description matches Wikidata, Non-coding RNA, All stub ...
... is a non-coding RNA that is an antisense inhibitor of cell division gene ftsZ. DicF is bound by the Hfq protein which ... Page for DicF RNA at Rfam v t e (Articles with short description, Short description matches Wikidata, GO template errors, Non- ... Tétart F, Bouché JP (March 1992). "Regulation of the expression of the cell-cycle gene ftsZ by DicF antisense RNA. Division ... Faubladier M, Cam K, Bouché JP (April 1990). "Escherichia coli cell division inhibitor DicF-RNA of the dicB operon. Evidence ...
The IS128 RNA is a non-coding RNA found in bacteria such as Escherichia coli and Shigella flexneri. The RNA is 209 nucleotides ... The function of this RNA is unknown. IS061 RNA IS102 RNA Tjaden B, Saxena RM, Stolyar S, Haynor DR, Kolker E, Rosenow C ( ... Page for IS128 RNA at Rfam v t e (Non-coding RNA, All stub articles, Molecular and cellular biology stubs). ... The IS128 RNA was initially identified in a computational screen of the E. coli genome. ...

No FAQ available that match "rna"

No images available that match "rna"