scholarly journals A Victorivirus and Two Novel Mitoviruses Co-Infected the Plant Pathogen Nigrospora oryzae

Viruses ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 83 ◽  
Author(s):  
Hong Liu ◽  
Rui Liu ◽  
Chang Li ◽  
Hui Wang ◽  
Hong Zhu ◽  
...  

Three dsRNAs, in sizes of approximately 2.5–5 kbp, were detected in the plant pathogenic fungus Nigrospora oryzae strain CS-7.5-4. Genomic analysis showed that the 5.0 kb dsRNA was a victorivirus named as Nigrospora oryzae victorivirus 2 (NoRV2). The genome of NoRV2 was 5166 bp in length containing two overlapping open reading frames (ORFs), ORF1 and ORF2. ORF1 was deduced to encode a coat protein (CP) showing homology to the CPs of viruses belonging to the Totiviridae family. The stop codon of ORF1 and the start codon of ORF2 were overlapped by the tetranucleotide sequence AUGA. ORF2 was predicted to encode an RNA-dependent RNA polymerase (RdRp), which was highly similar to the RdRps of victoriviruses. Virus-like particle examination demonstrated that the genome of NoRV2 was solely encapsidated by viral particles with a diameter of approximately 35 nm. The other two dsRNAs that were less than 3.0 kb were predicted to be the genomes of two mitoviruses, named as Nigrospora oryzae mitovirus 1 (NoMV1) and Nigrospora oryzae mitovirus 2 (NoMV2). Both NoMV1 and NoMV2 were A-U rich and with lengths of 2865 and 2507 bp, respectively. Mitochondrial codon usage inferred that each of the two mitoviruses contains a major large ORF encoding a mitoviral RdRp. Horizontal transfer experiments showed that the NoMV1 and NoMV2 could be cotransmitted horizontally via hyphal contact to other virus-free N. oryzae strains and causes phenotypic change to the recipient, such as an increase in growth rate. This is the first report of mitoviruses in N. oryzae.

2021 ◽  
Author(s):  
Yating Liu ◽  
Joseph Dougherty

Whole genome sequencing of patient populations is identifying thousands of new variants in UnTranslated Regions(UTRs). While the consequences of UTR mutations are not as easily predicted from primary sequence as coding mutations are, there are some known features of UTRs modulate their function. utR.annotation is an R package that can be used to annotate potential deleterious variants in the UTR regions for both human and mouse species. Given a CSV or VCF format variant file, utR.annotation provides information of each variant on whether and how it alters known translational regulators including:upstream Open Reading Frames (uORFs), upstream Kozak sequences, polyA signals, the Kozak sequence at the annotated translation initiation site, start codon, and stop codon, conservation scores in the variant position, and whether and how it changes ribosome loading based on a model from empirical data.


2012 ◽  
Vol 78 (19) ◽  
pp. 7082-7089 ◽  
Author(s):  
Y. S. Lapteva ◽  
O. E. Zolova ◽  
M. G. Shlyapnikov ◽  
I. M. Tsfasman ◽  
T. A. Muranova ◽  
...  

ABSTRACTLytic enzymes are the group of hydrolases that break down structural polymers of the cell walls of various microorganisms. In this work, we determined the nucleotide sequences of theLysobactersp. strain XL1alpAandalpBgenes, which code for, respectively, secreted lytic endopeptidases L1 (AlpA) and L5 (AlpB).In silicoanalysis of their amino acid sequences showed these endopeptidases to be homologous proteins synthesized as precursors similar in structural organization: the mature enzyme sequence is preceded by an N-terminal signal peptide and a pro region. On the basis of phylogenetic analysis, endopeptidases AlpA and AlpB were assigned to the S1E family [clan PA(S)] of serine peptidases. Expression of thealpAandalpBopen reading frames (ORFs) inEscherichia coliconfirmed that they code for functionally active lytic enzymes. Each ORF was predicted to have the Shine-Dalgarno sequence located at a canonical distance from the start codon and a potential Rho-independent transcription terminator immediately after the stop codon. ThealpAandalpBmRNAs were experimentally found to be monocistronic; transcription start points were determined for both mRNAs. The synthesis of thealpAandalpBmRNAs was shown to occur predominantly in the late logarithmic growth phase. The amount ofalpAmRNA in cells ofLysobactersp. strain XL1 was much higher, which correlates with greater production of endopeptidase L1 than of L5.


Author(s):  
Delano James ◽  
James Phelan ◽  
Daniel Sanderson

Blackcurrant leaf chlorosis associated virus (BCLCaV) was detected recently by next-generation sequencing (NGS) and proposed as a new and distinct species in the genus Idaeovirus. Genomic components of BCLCaV that were detected and confirmed include: 1) RNA-1 that is monocistronic and encodes the replicase complex; 2) a bicistronic RNA-2 that encodes a movement protein (MP) and the coat protein (CP) of the virus, with open reading frames (ORF) that overlap by a single adenine (A) nucleotide (nt) representing the third position of an opal stop codon of the MP ORF2a and the first position of the start codon of the CP ORF2b; 3) a subgenomic form of RNA-2 (RNA-3) that contains ORF2b; and 4) a concatenated form of RNA-2 that consists of a complementary and inverted RNA-3 conjoined to the full-length RNA-2. Analysis of NGS-derived paired-end reads revealed the existence of bridge reads encompassing the 3’-terminus and 5’-terminus of RNA-2 or RNA-3 of BCLCaV. The full RNA-2 or RNA-3 could be amplified using outward facing or abutting primers; also RNA-2/RNA-3 could be detected even after three consecutive RNase R enzyme treatments with denaturation at 95 oC preceding each digestion. Evidence was obtained indicating that there are circular forms of BCLCaV RNA-2 and RNA-3.


2019 ◽  
Vol 7 (11) ◽  
pp. 507 ◽  
Author(s):  
Jiaqi You ◽  
Kang Zhou ◽  
Xiaolin Liu ◽  
Mingde Wu ◽  
Long Yang ◽  
...  

Trichoderma species are a group of fungi which is widely distributed in major terrestrial ecosystems; they are also commonly used as biocontrol agents for many plant diseases. A virus, namely Trichoderma harzianum hypovirus 1 (ThHV1), was identified in T. harzianum isolate T-70, and also infected isolate T-70D, together with its defective RNA (ThHV1-S). The ThHV1 genome possessed two Open Reading Frames (ORFs), namely ORF1 and ORF2. The start codon of ORF2 overlapped with the stop codon of ORF1 in a 43 nt long region. The polypeptide encoded by ORF2 of ThHV1 shared sequence similarities with those of betahypoviruses, indicating that ThHV1 is a novel member of Hypoviridea. Isolate T-70D, carrying both ThHV1 and ThHV1-S, showed abnormal biological properties, notably a decreased mycoparasitism ability when compared with isolate T-70. Both ThHV1 and ThHV1-S could be vertically transmitted to conidia and horizontally transmitted to T. harzianum isolate T-68 and T. koningiopsis T-51. The derivative strains carrying both ThHV1 and ThHV1-S showed decreased mycoparasitism ability, whereas strains carrying ThHV1 alone were normal, indicating that ThHV1-S is closely associated with the decreased mycoparasitism ability of T. harzianum isolate T-70D. ThHV1 was widely detected in isolates of T. harzianum, T. koningiopsis and T. atroviride originating from soil of China. Therefore, viruses in fungal biocontrol agents may also be a factor associated with the stability of their application.


Viruses ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 54 ◽  
Author(s):  
Yoyeon Cha ◽  
Jihwan Chun ◽  
Bokyung Son ◽  
Sangryeol Ryu

Staphylococcus aureus is one of the notable human pathogens that can be easily encountered in both dietary and clinical surroundings. Among various countermeasures, bacteriophage therapy is recognized as an alternative method for resolving the issue of antibiotic resistance. In the current study, bacteriophage CSA13 was isolated from a chicken, and subsequently, its morphology, physiology, and genomics were characterized. This Podoviridae phage displayed an extended host inhibition effect of up to 23 hours of persistence. Its broad host spectrum included methicillin susceptible S. aureus (MSSA), methicillin resistant S. aureus (MRSA), local S. aureus isolates, as well as non-aureus staphylococci strains. Moreover, phage CSA13 could successfully remove over 78% and 93% of MSSA and MRSA biofilms in an experimental setting, respectively. Genomic analysis revealed a 17,034 bp chromosome containing 18 predicted open reading frames (ORFs) without tRNAs, representing a typical chromosomal structure of the staphylococcal Podoviridae family. The results presented here suggest that phage CSA13 can be applicable as an effective biocontrol agent against S. aureus.


2008 ◽  
Vol 190 (18) ◽  
pp. 6111-6118 ◽  
Author(s):  
P. Rousseau ◽  
C. Loot ◽  
C. Turlan ◽  
S. Nolivos ◽  
M. Chandler

ABSTRACT IS911 is a bacterial insertion sequence composed of two consecutive overlapping open reading frames (ORFs [orfA and orfB]) encoding the transposase (OrfAB) as well as a regulatory protein (OrfA). These ORFs are bordered by terminal left and right inverted repeats (IRL and IRR, respectively) with several differences in nucleotide sequence. IS911 transposition is asymmetric: each end is cleaved on one strand to generate a free 3′-OH, which is then used as the nucleophile in attacking the opposite insertion sequence (IS) end to generate a free IS circle. This will be inserted into a new target site. We show here that the ends exhibit functional differences which, in vivo, may favor the use of one compared to the other during transposition. Electromobility shift assays showed that a truncated form of the transposase [OrfAB(1-149)] exhibits higher affinity for IRR than for IRL. While there was no detectable difference in IR activities during the early steps of transposition, IRR was more efficient during the final insertion steps. We show here that the differential activities between the two IRs correlate with the different affinities of OrfAB(1-149) for the IRs during assembly of the nucleoprotein complexes leading to transposition. We conclude that the two inverted repeats are not equivalent during IS911 transposition and that this asymmetry may intervene to determine the ordered assembly of the different protein-DNA complexes involved in the reaction.


2021 ◽  
Author(s):  
Yang Sun ◽  
Yan qiong Li ◽  
Wen han Dong ◽  
Ai li Sun ◽  
Ning wei Chen ◽  
...  

Abstract The complete genome of the dsRNA virus isolated from Rhizoctonia solani AG-1 IA 9–11 (designated as Rhizoctonia solani dsRNA virus 11, RsRV11 ) were determined. The RsRV11 genome was 9,555 bp in length, contained three conserved domains, SMC, PRK and RT-like super family, and encoded two non-overlapping open reading frames (ORFs). ORF1 potentially coded for a 204.12 kDa predicted protein, which shared low but significant amino acid sequence identities with the putative protein encoded by Rhizoctonia solani RNA virus HN008 (RsRV-HN008) ORF1. ORF2 potentially coded for a 132.41 kDa protein which contained the conserved motifs of the RNA-dependent RNA polymerase (RdRp). Phylogenetic analysis indicated that RsRV11 was clustered with RsRV-HN008 in a separate clade independent of other virus families. It implies that RsRV11, along with RsRV-HN008 possibly a new fungal virus taxa closed to the family Megabirnaviridae, and RsRV11 is a new member of mycoviruses.


2019 ◽  
Vol 8 (43) ◽  
Author(s):  
T. O. C. Faleye ◽  
O. M. Adewumi ◽  
D. Klapsa ◽  
M. Majumdar ◽  
J. Martin ◽  
...  

Here, we describe nearly complete genome sequences (7,361 nucleotides [nt] and 6,893 nt) of two echovirus 20 (E20) isolates from Nigeria that were simultaneously typed as CVB and E20 (dual serotype) by neutralization assay. Both include two overlapping open reading frames (ORFs) of 67 and 2,183 amino acids that encoded a recently described gut infection-facilitating protein and the classic enterovirus proteins, respectively.


Author(s):  
Dylan Aïssi ◽  
Omar Soukarieh ◽  
Carole Proust ◽  
Beatrice Jaspard-Vinassa ◽  
Pierre Fautrad ◽  
...  

AbstractSummaryVariants in 5’UTR regions that create upstream translation initiation AUG codons are a class of neglected non coding variations. When they associate with a premature stop codon and create upstream open reading frames (uORFs) whose translation competes with that of natural proteins, they can have strong impact on human diseases. We here describe MORFEE, a new bioinformatics tool that detects, annotates and predicts, from a standard VCF file, the creation of uORF by any 5’UTR variants on uORF creation. MORFEE was applied to two genomic resources and identified candidate functional variants that could explain statistical association signals observed in the context of Genome Wide Association Studies or could be responsible for rare forms of diseases. In conclusion MORFEE is an easy-to-use tool complementary to existing ones that can help resolving genetic investigations that remained so far unfruitful.Availability and implementationMORFEE is written in R with code and package available at https://github.com/daissi/[email protected]; [email protected]


2021 ◽  
Author(s):  
Hanna Retallack ◽  
Katerina D. Popova ◽  
Matthew T. Laurie ◽  
Sara Sunshine ◽  
Joseph L. DeRisi

Narnaviruses are RNA viruses detected in diverse fungi, plants, protists, arthropods and nematodes. Though initially described as simple single-gene non-segmented viruses encoding RNA-dependent RNA polymerase (RdRp), a subset of narnaviruses referred to as “ambigrammatic” harbor a unique genomic configuration consisting of overlapping open reading frames (ORFs) encoded on opposite strands. Phylogenetic analysis supports selection to maintain this unusual genome organization, but functional investigations are lacking. Here, we establish the mosquito-infecting Culex narnavirus 1 (CxNV1) as a model to investigate the functional role of overlapping ORFs in narnavirus replication. In CxNV1, a reverse ORF without homology to known proteins covers nearly the entire 3.2 kb segment encoding the RdRp. Additionally, two opposing and nearly completely overlapping novel ORFs are found on the second putative CxNV1 segment, the 0.8 kb “Robin” RNA. We developed a system to launch CxNV1 in a naïve mosquito cell line, then showed that functional RdRp is required for persistence of both segments, and an intact reverse ORF is required on the RdRp segment for persistence. Mass spectrometry of persistently CxNV1-infected cells provided evidence for translation of this reverse ORF. Finally, ribosome profiling yielded a striking pattern of footprints for all four CxNV1 RNA strands that was distinct from actively-translating ribosomes on host mRNA or co-infecting RNA viruses. Taken together, these data raise the possibility that the process of translation itself is important for persistence of ambigrammatic narnaviruses, potentially by protecting viral RNA with ribosomes, thus suggesting a heretofore undescribed viral tactic for replication and transmission. IMPORTANCE Fundamental to our understanding of RNA viruses is a description of which strand(s) of RNA are transmitted as the viral genome, relative to which encode the viral proteins. Ambigrammatic narnaviruses break the mold. These viruses, found broadly in fungi, plants, and insects, have the unique feature of two overlapping genes encoded on opposite strands, comprising nearly the full length of the viral genome. Such extensive overlap is not seen in other RNA viruses, and comes at the cost of reduced evolutionary flexibility in the sequence. The present study is motivated by investigating the benefits which balance that cost. We show for the first time a functional requirement for the ambigrammatic genome configuration in Culex narnavirus 1, which suggests a model for how translation of both strands might benefit this virus. Our work highlights a new blueprint for viral persistence, distinct from strategies defined by canonical definitions of the coding strand.


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