scholarly journals Forced Evolution Reveals the Importance of Short Open Reading Frame A and Secondary Structure in the Cauliflower Mosaic Virus 35S RNA Leader

1998 ◽  
Vol 72 (5) ◽  
pp. 4157-4169 ◽  
Author(s):  
Mikhail M. Pooggin ◽  
Thomas Hohn ◽  
Johannes Fütterer
Keyword(s):  
Secondary Structure ◽  
Mosaic Virus ◽  
Pcr Amplification ◽  
Cauliflower Mosaic Virus ◽  
Open Reading Frames ◽  
Reading Frame ◽  
Short Open Reading Frame ◽  
The Stability ◽  
Virus Replication Cycle ◽  
Reading Frames

ABSTRACT Cauliflower mosaic virus pregenomic 35S RNA begins with a long leader sequence containing an extensive secondary structure and up to nine short open reading frames (sORFs), 2 to 35 codons in length. To test whether any of these sORFs are required for virus viability, their start codons were mutated either individually or in various combinations. The resulting viral mutants were tested for infectivity on mechanically inoculated turnip plants. Viable mutants were passaged several times, and the stability of the introduced mutations was analyzed by PCR amplification and sequencing. Mutations at the 5′-proximal sORF A and in the center of the leader resulted in delayed symptom development and in the appearance of revertants. In the central leader region, the predicted secondary structure, rather than the sORF organization, was restored, while true reversions or second-site substitutions in response to mutations of sORF A restored this sORF. Involvement of sORF A and secondary structure of the leader in the virus replication cycle, and especially in translation of the 35S RNA via ribosome shunting, is discussed.

scholarly journals Continuous and Discontinuous Ribosome Scanning on the Cauliflower Mosaic Virus 35 S RNA Leader Is Controlled by Short Open Reading Frames

2000 ◽  
Vol 275 (47) ◽  
pp. 37278-37284 ◽  
Author(s):  
Lyubov A. Ryabova ◽  
Mikhail M. Pooggin ◽  
Diana Ines Dominguez ◽  
Thomas Hohn
Keyword(s):  
Mosaic Virus ◽  
Cauliflower Mosaic Virus ◽  
Open Reading Frames ◽  
Reading Frames

scholarly journals Evidence for a Dual Strategy in the Expression of Cauliflower Mosaic Virus Open Reading Frames I and IV

1998 ◽  
Vol 42 (4) ◽  
pp. 329-334 ◽  
Author(s):  
Kappei Kobayashi ◽  
Seiji Tsuge ◽  
Hitoshi Nakayashiki ◽  
Kazuyuki Mise ◽  
Iwao Furusawa
Keyword(s):  
Mosaic Virus ◽  
Cauliflower Mosaic Virus ◽  
Open Reading Frames ◽  
Dual Strategy ◽  
Reading Frames

scholarly journals Evolutionary History of Cucumber Mosaic Virus Deduced by Phylogenetic Analyses

2002 ◽  
Vol 76 (7) ◽  
pp. 3382-3387 ◽  
Author(s):  
Marilyn J. Roossinck
Keyword(s):  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
Virus Isolate ◽  
Phylogenetic Analyses ◽  
Open Reading Frames ◽  
Broad Host Range ◽  
Nontranslated Region ◽  
History Of ◽  
Evolutionary Success ◽  
Reading Frames

ABSTRACT Cucumber mosaic virus (CMV) is an RNA plant virus with a tripartite genome and an extremely broad host range. Previous evolutionary analyses with the coat protein (CP) and 5′ nontranslated region (NTR) of RNA 3 suggested subdivision of the virus into three groups, subgroups IA, IB, and II. In this study 15 strains of CMV whose nucleotide sequences have been determined were used for a complete phylogenetic analysis of the virus. The trees estimated for open reading frames (ORFs) located on the different RNAs were not congruent and did not completely support the subgrouping indicated by the CP ORF, indicating that different RNAs had independent evolutionary histories. This is consistent with a reassortment mechanism playing an important role in the evolution of the virus. The evolutionary trees of the 1a and 3a ORFs were more compact and displayed more branching than did those of the 2a and CP ORFs. This may reflect more rigid host-interactive constraints exerted on the 1a and 3a ORFs. In addition, analysis of the 3′ NTR that is conserved among all RNAs indicated that evolutionary constraints on this region are specific to the RNA component rather than the virus isolate. This indicates that functions other than replication are encoded in the 3′ NTR. Reassortment may have led to the genetic diversity found among CMV strains and contributed to its enormous evolutionary success.

The positive regulatory function of the 5'-proximal open reading frames in GCN4 mRNA can be mimicked by heterologous, short coding sequences

1988 ◽  
Vol 8 (9) ◽  
pp. 3827-3836
Author(s):  
N P Williams ◽  
P P Mueller ◽  
A G Hinnebusch
Keyword(s):  
Translational Control ◽  
Normal Growth ◽  
Regulatory Elements ◽  
Growth Conditions ◽  
Open Reading Frames ◽  
Regulatory Function ◽  
Yeast Saccharomyces Cerevisiae ◽  
Reading Frame ◽  
Yeast Genes ◽  
Reading Frames

Translational control of GCN4 expression in the yeast Saccharomyces cerevisiae is mediated by multiple AUG codons present in the leader of GCN4 mRNA, each of which initiates a short open reading frame of only two or three codons. Upstream AUG codons 3 and 4 are required to repress GCN4 expression in normal growth conditions; AUG codons 1 and 2 are needed to overcome this repression in amino acid starvation conditions. We show that the regulatory function of AUG codons 1 and 2 can be qualitatively mimicked by the AUG codons of two heterologous upstream open reading frames (URFs) containing the initiation regions of the yeast genes PGK and TRP1. These AUG codons inhibit GCN4 expression when present singly in the mRNA leader; however, they stimulate GCN4 expression in derepressing conditions when inserted upstream from AUG codons 3 and 4. This finding supports the idea that AUG codons 1 and 2 function in the control mechanism as translation initiation sites and further suggests that suppression of the inhibitory effects of AUG codons 3 and 4 is a general consequence of the translation of URF 1 and 2 sequences upstream. Several observations suggest that AUG codons 3 and 4 are efficient initiation sites; however, these sequences do not act as positive regulatory elements when placed upstream from URF 1. This result suggests that efficient translation is only one of the important properties of the 5' proximal URFs in GCN4 mRNA. We propose that a second property is the ability to permit reinitiation following termination of translation and that URF 1 is optimized for this regulatory function.

scholarly journals YeATS - a tool suite for analyzing RNA-seq derived transcriptome identifies a highly transcribed putative extensin in heartwood/sapwood transition zone in black walnut

F1000Research ◽  
2015 ◽  
Vol 4 ◽  
pp. 155 ◽  
Author(s):  
Sandeep Chakraborty ◽  
Monica Britton ◽  
Jill Wegrzyn ◽  
Timothy Butterfield ◽  
Pedro José Martínez-García ◽  
...  
Keyword(s):  
Transition Zone ◽  
Transcript Abundance ◽  
Black Walnut ◽  
Open Reading Frames ◽  
Rna Seq ◽  
Reading Frame ◽  
Homologous Genes ◽  
Associated Proteins ◽  
Molecular Components ◽  
Reading Frames

The transcriptome provides a functional footprint of the genome by enumerating the molecular components of cells and tissues. The field of transcript discovery has been revolutionized through high-throughput mRNA sequencing (RNA-seq). Here, we present a methodology that replicates and improves existing methodologies, and implements a workflow for error estimation and correction followed by genome annotation and transcript abundance estimation for RNA-seq derived transcriptome sequences (YeATS - Yet Another Tool Suite for analyzing RNA-seq derived transcriptome). A unique feature of YeATS is the upfront determination of the errors in the sequencing or transcript assembly process by analyzing open reading frames of transcripts. YeATS identifies transcripts that have not been merged, result in broken open reading frames or contain long repeats as erroneous transcripts. We present the YeATS workflow using a representative sample of the transcriptome from the tissue at the heartwood/sapwood transition zone in black walnut. A novel feature of the transcriptome that emerged from our analysis was the identification of a highly abundant transcript that had no known homologous genes (GenBank accession: KT023102). The amino acid composition of the longest open reading frame of this gene classifies this as a putative extensin. Also, we corroborated the transcriptional abundance of proline-rich proteins, dehydrins, senescence-associated proteins, and the DNAJ family of chaperone proteins. Thus, YeATS presents a workflow for analyzing RNA-seq data with several innovative features that differentiate it from existing software.

scholarly journals Coupled Translation of the Respiratory Syncytial Virus M2 Open Reading Frames Requires Upstream Sequences

2005 ◽  
Vol 280 (23) ◽  
pp. 21972-21980 ◽  
Author(s):  
Phillip S. Gould ◽  
Andrew J. Easton
Keyword(s):  
Respiratory Syncytial Virus ◽  
Secondary Structure ◽  
Significant Degree ◽  
Open Reading Frames ◽  
Translation Process ◽  
Reading Frame ◽  
Coupling Process ◽  
Important Region ◽  
Syncytial Virus ◽  
Overlap Region

We have investigated the mechanism of the translation of the second open reading frame (ORF) of the respiratory syncytial virus M2 transcript that uses a novel coupled translation process requiring prior translation of the upstream ORF. The second M2-2 ORF sequences play no role in the coupling process and can be replaced with other gene sequences. Surprisingly, the overlap region of the two ORFs alone was not sufficient for coupled translation to occur. An analysis of the sequences required for the coupling process showed that portions of the transcript located along the length of the first ORF M2-1, upstream of the ORF overlap region, were essential for coupled translation to occur. A critically important region for this process was centered ∼150 nucleotides upstream of the ORF2 initiation codons. This region was shown to contain a significant degree of secondary structure, and mutation of this sequence to remove predicted areas of base pairing significantly reduced coupled translation, confirming that the secondary structure was important for the coupling process. Additional sequences further upstream increased the efficiency of the coupled translation process. These data indicate that upstream sequences act in conjunction with the M2-1/M2-2 overlap region to promote coupled translation.

scholarly journals High Genetic Variability of the agr Locus in Staphylococcus Species

2002 ◽  
Vol 184 (4) ◽  
pp. 1180-1186 ◽  
Author(s):  
Philippe Dufour ◽  
Sophie Jarraud ◽  
Francois Vandenesch ◽  
Timothy Greenland ◽  
Richard P. Novick ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Quorum Sensing ◽  
Sequence Divergence ◽  
Pcr Amplification ◽  
Variable Region ◽  
Cysteine Residue ◽  
Multiple Alignment ◽  
Open Reading Frames ◽  
Signal Transduction System ◽  
Reading Frames

ABSTRACT The agr quorum-sensing and signal transduction system was initially described in Staphylococcus aureus, where four distinct allelic variants have been sequenced. Western blotting suggests the presence of homologous loci in many other staphylococci, and this has been confirmed for S. epidermidis and S. lugdunensis. In this study we isolated agr-like loci from a range of staphylococci by using PCR amplification from primers common to the six published agr sequences and bracketing the most variable region, associated with quorum-sensing specificity. Positive amplifications were obtained from 14 of 34 staphylococcal species or subspecies tested. Sequences of the amplicons identified 24 distinct variants which exhibited extensive sequence divergence with only 10% of the nucleotides absolutely conserved on multiple alignment. This variability involved all three open reading frames involved in quorum sensing and signal transduction. However, these variants retained several protein signatures, including the conserved cysteine residue of the autoinducing peptide, with the exception of S. intermedius of pigeon origin, which contained a serine in place of cysteine at this position. We discuss hypotheses on the mode of action and the molecular evolution of the agr locus based on comparisons between the newly determined sequences.

SOME HINTS ON OPEN READING FRAME STATISTICS — HOW ORF LENGTH DEPENDS ON SELECTION

1999 ◽  
Vol 10 (04) ◽  
pp. 635-643 ◽  
Author(s):  
AGNIESZKA GIERLIK ◽  
PAWEŁ MACKIEWICZ ◽  
MARIA KOWALCZUK ◽  
STANISŁAW CEBRAT ◽  
MIROSŁAW R. DUDEK
Keyword(s):  
Genetic Code ◽  
Dna Sequences ◽  
Nucleotide Composition ◽  
Open Reading Frames ◽  
Open Reading Frame ◽  
Antisense Strand ◽  
Coding Sequences ◽  
Reading Frame ◽  
Intergenic Sequences ◽  
Reading Frames

Coding sequences of DNA generate Open Reading Frames (ORFs) inside them with much higher frequency than random DNA sequences do, especially in the antisense strand. This is a specific feature of the genetic code. Since coding sequences are selected for their length, the generated ORFs are indirect results of this selection and their length is also influenced by selection. That is why ORFs found in any genome, even much longer ones than those spontaneously generated in random DNA sequences, should be considered as two different sets of ORFs: The first one coding for proteins, the second one generated by the coding ORFs. Even intergenic sequences possess greater capacity for generating ORFs than random DNA sequences of the same nucleotide composition, which seems to be a premise that intergenic sequences were generated from coding sequences by recombinational mechanisms.

scholarly journals Crystal Structure of F-93 from Sulfolobus Spindle-Shaped Virus 1, a Winged-Helix DNA Binding Protein

2004 ◽  
Vol 78 (21) ◽  
pp. 11544-11550 ◽  
Author(s):  
Paul Kraft ◽  
Andrea Oeckinghaus ◽  
Daniel Kümmel ◽  
George H. Gauss ◽  
John Gilmore ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Dna Binding ◽  
Hot Springs ◽  
Sequence Similarity ◽  
Open Reading Frames ◽  
Target Sequence ◽  
Winged Helix ◽  
Reading Frame ◽  
Biochemical Analyses ◽  
Reading Frames

ABSTRACT Sulfolobus spindle-shaped viruses (SSVs), or Fuselloviridae, are ubiquitous crenarchaeal viruses found in high-temperature acidic hot springs around the world (pH ≤4.0; temperature of ≥70°C). Because they are relatively easy to isolate, they represent the best studied of the crenarchaeal viruses. This is particularly true for the type virus, SSV1, which contains a double-stranded DNA genome of 15.5 kilobases, encoding 34 putative open reading frames. Interestingly, the genome shows little sequence similarity to organisms other than its SSV homologues. Together, sequence similarity and biochemical analyses have suggested functions for only 6 of the 34 open reading frames. Thus, even though SSV1 is the best-studied crenarchaeal virus, functions for most (28) of its open reading frames remain unknown. We have undertaken biochemical and structural studies for the gene product of open reading frame F-93. We find that F-93 exists as a homodimer in solution and that a tight dimer is also present in the 2.7-Å crystal structure. Further, the crystal structure reveals a fold that is homologous to the SlyA and MarR subfamilies of winged-helix DNA binding proteins. This strongly suggests that F-93 functions as a transcription factor that recognizes a (pseudo-)palindromic DNA target sequence.

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