scholarly journals Reverse transcriptase-related enzymes are associated with horizontal chromosome transfer in an asexual pathogen

2015 ◽  
Author(s):  
Xiaoqiu Huang ◽  
Anindya Das ◽  
Binod B Sahu ◽  
Subodh K Srivastava ◽  
Leonor F Leandro ◽  
...  
Keyword(s):  
Reverse Transcriptase ◽  
Root Rot ◽  
Supernumerary Chromosome ◽  
Open Reading Frames ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Chromosome Transfer ◽  
Supernumerary Chromosomes ◽  
The Mean ◽  
Reading Frames

Supernumerary chromosomes have been shown to transfer horizontally from one isolate to another. However, the mechanism by which horizontal chromosome transfer (HCT) occurs is unknown. In this study, we compared the genomes of 11 isolates comprising six Fusarium species that cause soybean sudden death syndrome (SDS) or bean root rot (BRR), and detected numerous instances of HCT in supernumerary chromosomes. We also identified a statistically significant number (21 standard deviations above the mean) of single nucleotide polymorphisms (SNPs) in the supernumerary chromosomes between isolates of the asexual pathogen F. virguliforme. Supernumerary chromosomes carried reverse transcriptase-related genes (RVT); the presence of long RVT open reading frames (ORFs) in the supernumerary chromosome was correlated with the presence of two or more chromosome copies with a significant number of SNPs between them. Our results suggest that supernumerary chromosomes transfer horizontally via an RNA intermediate. Understanding the mechanism by which HCT occurs will have a profound impact on understanding evolution and applying biotechnology as well as accepting HCT as a natural source of genetic variation.

scholarly journals Reverse transcriptase-related enzymes are associated with horizontal chromosome transfer in an asexual pathogen

2015 ◽  
Author(s):  
Xiaoqiu Huang ◽  
Anindya Das ◽  
Binod B Sahu ◽  
Subodh K Srivastava ◽  
Leonor F Leandro ◽  
...  
Keyword(s):  
Reverse Transcriptase ◽  
Root Rot ◽  
Supernumerary Chromosome ◽  
Open Reading Frames ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Chromosome Transfer ◽  
Supernumerary Chromosomes ◽  
The Mean ◽  
Reading Frames

Supernumerary chromosomes have been shown to transfer horizontally from one isolate to another. However, the mechanism by which horizontal chromosome transfer (HCT) occurs is unknown. In this study, we compared the genomes of 11 isolates comprising six Fusarium species that cause soybean sudden death syndrome (SDS) or bean root rot (BRR), and detected numerous instances of HCT in supernumerary chromosomes. We also identified a statistically significant number (21 standard deviations above the mean) of single nucleotide polymorphisms (SNPs) in the supernumerary chromosomes between isolates of the asexual pathogen F. virguliforme. Supernumerary chromosomes carried reverse transcriptase-related genes (RVT); the presence of long RVT open reading frames (ORFs) in the supernumerary chromosome was correlated with the presence of two or more chromosome copies with a significant number of SNPs between them. Our results suggest that supernumerary chromosomes transfer horizontally via an RNA intermediate. Understanding the mechanism by which HCT occurs will have a profound impact on understanding evolution and applying biotechnology as well as accepting HCT as a natural source of genetic variation.

Genetic diversity of limonene synthase genes in Rongan kumquat (Fortunella crassifolia)

2020 ◽  
Vol 47 (5) ◽  
pp. 425
Author(s):  
Mengyu Liu ◽  
Xiaofeng Liu ◽  
Junhua Hu ◽  
Yang Xue ◽  
Xiaochun Zhao
Keyword(s):  
Large Family ◽  
Open Reading Frames ◽  
Sequencing Analysis ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Geranyl Diphosphate ◽  
Limonene Synthase ◽  
High Amino Acid ◽  
Main Component ◽  
Reading Frames

D-limonene is the main component of citrus essential oils. In the monoterpene biosynthetic pathway, geranyl diphosphate reacts with monoterpenes to form the prenyl-carbocation intermediate to produce d-limonene. In this study, d-limonene synthase (FcLS) genes were first isolated from Rongan kumquat (Fortunella crassifolia Swingle). Sequencing analysis revealed that the open reading frames of 18 FcLS genes contain 12 single nucleotide polymorphisms, which resulted in the variation of FcLS proteins, indicating that the limonene synthase genes are a large family in F. crassifolia. This phenomenon has not been reported in Citrus. The predicted FcLS proteins showed a high amino acid sequence identity with other Citrus limonene synthases and also had the typical structures of limonene synthase protein. FcLS1 was validated to be a functional d-limonene synthase by prokaryotic expression.

scholarly journals FCoV Viral Sequences of Systemically Infected Healthy Cats Lack Gene Mutations Previously Linked to the Development of FIP

Pathogens ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 603
Author(s):  
Mirjam Lutz ◽  
Aline R. Steiner ◽  
Valentino Cattori ◽  
Regina Hofmann-Lehmann ◽  
Hans Lutz ◽  
...  
Keyword(s):  
Gene Mutations ◽  
Open Reading Frames ◽  
Nucleotide Polymorphisms ◽  
Nonstructural Proteins ◽  
Single Nucleotide ◽  
Systemic Spread ◽  
Viral Sequences ◽  
Highly Virulent ◽  
Reading Frames ◽  
S Genes

Feline Infectious Peritonitis (FIP)—the deadliest infectious disease of young cats in shelters or catteries—is induced by highly virulent feline coronaviruses (FCoVs) emerging in infected hosts after mutations of less virulent FCoVs. Previous studies have shown that some mutations in the open reading frames (ORF) 3c and 7b and the spike (S) gene have implications for the development of FIP, but mainly indirectly, likely also due to their association with systemic spread. The aim of the present study was to determine whether FCoV detected in organs of experimentally FCoV infected healthy cats carry some of these mutations. Viral RNA isolated from different tissues of seven asymptomatic cats infected with the field strains FCoV Zu1 or FCoV Zu3 was sequenced. Deletions in the 3c gene and mutations in the 7b and S genes that have been shown to have implications for the development of FIP were not detected, suggesting that these are not essential for systemic viral dissemination. However, deletions and single nucleotide polymorphisms leading to truncations were detected in all nonstructural proteins. These were found across all analyzed ORFs, but with significantly higher frequency in ORF 7b than ORF 3a. Additionally, a previously unknown homologous recombination site was detected in FCoV Zu1.

scholarly journals Pangaea and the Out-of-Africa Model of Varicella-Zoster Virus Evolution and Phylogeography

2012 ◽  
Vol 86 (18) ◽  
pp. 9558-9565 ◽  
Author(s):  
Charles Grose
Keyword(s):  
Varicella Zoster Virus ◽  
Open Reading Frames ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Content Type ◽  
Varicella Zoster ◽  
Building Models ◽  
Anatomically Modern Humans ◽  
Tree Building ◽  
Reading Frames

The goal of this minireview is to provide an overview of varicella-zoster virus (VZV) phylogenetics and phylogeography when placed in the broad context of geologic time. Planet Earth was formed over 4 billion years ago, and the supercontinent Pangaea coalesced around 400 million years ago (mya). Based on detailed tree-building models, the base of the phylogenetic tree of theHerpesviridaefamily has been estimated at 400 mya. Subsequently, Pangaea split into Laurasia and Gondwanaland; in turn, Africa rifted from Gondwanaland. Based on available data, the hypothesis of this minireview is that the ancestral alphaherpesvirus VZV coevolved in simians, apes, and hominins in Africa. When anatomically modern humans first crossed over the Red Sea 60,000 years ago, VZV was carried along in their dorsal root ganglia. Currently, there are five VZV clades, distinguishable by single nucleotide polymorphisms. These clades likely represent continued VZV coevolution, as humans with latent VZV infection left Arabia and dispersed into Asia (clades 2 and 5) and Europe (clades 1, 3, and 4). The prototype VZV sequence contains nearly 125,000 bp, divided into 70 open reading frames. Generally, isolates within a clade display >99.9% identity to one another, while members of one clade compared to a second clade show 99.8% identity to one another. Recently, four different VZV genotypes that do not segregate into the previously defined five clades have been identified, a result indicating a wider than anticipated diversity among newly collected VZV strains around the world.

Assessing single nucleotide polymorphism selection methods for the development of a low-density panel optimized for imputation in South African Drakensberger beef cattle

2021 ◽  
Author(s):  
Simon F Lashmar ◽  
Donagh P Berry ◽  
Rian Pierneef ◽  
Farai C Muchadeyi ◽  
Carina Visser
Keyword(s):  
South African ◽  
Clustering Algorithm ◽  
Imputation Accuracy ◽  
Developed Countries ◽  
Genotype Imputation ◽  
Selection Strategy ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Single Nucleotide Polymorphism Selection ◽  
The Mean

Abstract A major obstacle in applying genomic selection (GS) to uniquely adapted local breeds in less-developed countries has been the cost of genotyping at high densities of single nucleotide polymorphisms (SNP). Cost reduction can be achieved by imputing genotypes from lower to higher densities. Locally adapted breeds tend to be admixed and exhibit a high degree of genomic heterogeneity thus necessitating the optimization of SNP selection for downstream imputation. The aim of this study was to quantify the achievable imputation accuracy for a sample of 1,135 South African (SA) Drakensberger using several custom-derived lower-density panels varying in both SNP density and how the SNP were selected. From a pool of 120,608 genotyped SNP, subsets of SNP were chosen 1) at random, 2) with even genomic dispersion, 3) by maximizing the mean minor allele frequency (MAF), 4) using a combined score of MAF and linkage disequilibrium (LD), 5) using a partitioning-around-medoids (PAM) algorithm, and finally 6) using a hierarchical LD-based clustering algorithm. Imputation accuracy to higher density improved as SNP density increased; animal-wise imputation accuracy defined as the within-animal correlation between the imputed and actual alleles ranged from 0.625 to 0.990 when 2,500 randomly selected SNP were chosen versus a range of 0.918 to 0.999 when 50,000 randomly selected SNP were used. At a panel density of 10,000 SNP, the mean (standard deviation) animal-wise allele concordance rate was 0.976 (0.018) versus 0.982 (0.014) when the worst (i.e., random) as opposed to the best (i.e., combination of MAF and LD) SNP selection strategy was employed. A difference of 0.071 units was observed between the mean correlation-based accuracy of imputed SNP categorized as low (0.01<MAF≤0.1) versus high MAF (0.4<MAF≤0.5). Greater mean imputation accuracy was achieved for SNP located on autosomal extremes when these regions were populated with more SNP. The presented results suggested that genotype imputation can be a practical cost-saving strategy for indigenous breeds such as the South African Drakensberger. Based on the results, a genotyping panel consisting of approximately 10,000 SNP selected based on a combination of MAF and LD would suffice in achieving a less than 3% imputation error rate for a breed characterized by genomic admixture on the condition that these SNP are selected based on breed-specific selection criteria.

scholarly journals The German Shorthair Pointer Dog Breed (Canis lupus familiaris): Genomic Inbreeding and Variability

Animals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 498 ◽  
Author(s):  
Antonio Boccardo ◽  
Stefano Paolo Marelli ◽  
Davide Pravettoni ◽  
Alessandro Bagnato ◽  
Giuseppe Achille Busca ◽  
...  
Keyword(s):  
Canis Lupus ◽  
Inbreeding Coefficient ◽  
Nucleotide Polymorphisms ◽  
Canis Lupus Familiaris ◽  
Runs Of Homozygosity ◽  
Single Nucleotide ◽  
The Mean ◽  
Dog Breed ◽  
Genomic Inbreeding ◽  
Genealogical Information

The German Shorthaired Pointer (GSHP) is a breed worldwide known for its hunting versatility. Dogs of this breed are appreciated as valuable companions, effective trackers, field trailers and obedience athletes. The aim of the present work is to describe the genomic architecture of the GSHP breed and to analyze inbreeding levels under a genomic and a genealogic perspective. A total of 34 samples were collected (24 Italian, 10 USA), and the genomic and pedigree coefficients of inbreeding have been calculated. A total of 3183 runs of homozygosity (ROH) across all 34 dogs have been identified. The minimum and maximum number of Single Nucleotide Polymorphisms (SNPs) defining all ROH are 40 and 3060. The mean number of ROH for the sample was 93.6. ROH were found on all chromosomes. A total of 854 SNPs (TOP_SNPs) defined 11 ROH island regions (TOP_ROH), in which some gene already associated with behavioral and morphological canine traits was annotated. The proportion of averaged observed homozygotes estimated on total number of SNPs was 0.70. The genomic inbreeding coefficient based on ROH was 0.17. The mean inbreeding based on genealogical information resulted 0.023. The results describe a low inbred population with quite a good level of genetic variability.

scholarly journals An in vivo assay for the reverse transcriptase of human retrotransposon L1 in Saccharomyces cerevisiae.

1994 ◽  
Vol 14 (7) ◽  
pp. 4485-4492 ◽  
Author(s):  
B A Dombroski ◽  
Q Feng ◽  
S L Mathias ◽  
D M Sassaman ◽  
A F Scott ◽  
...  
Keyword(s):  
Reverse Transcriptase ◽  
Consensus Sequence ◽  
Unknown Origin ◽  
Open Reading Frames ◽  
Long Terminal Repeats ◽  
Base Pairs ◽  
In Vivo Assay ◽  
Reading Frames

L1 elements constitute a highly repetitive human DNA family (50,000 to 100,000 copies) lacking long terminal repeats and ending in a poly(A) tail. Some L1 elements are capable of retrotransposition in the human genome (Kazazian, H. H., Jr., C. Wong, H. Youssoufian, A. F. Scott, D. G. Phillips, and S.E. Antonarakis, Nature (London) 332:164-166, 1988). Although most are 5' truncated, a consensus sequence of complete L1 elements is 6 kb long and contains two open reading frames (ORFs) (Scott, A. F., B. J. Schmeckpeper, M. Abdelrazik, C. T. Comey, B. O'Hara, J. P. Rossiter, T. Cooley, P. Health, K. D. Smith, and L. Margolet, Genomics 1:113-125, 1987). The protein encoded by ORF2 has reverse transcriptase (RT) activity in vitro (Mathias, S. L., A. F. Scott, H. H. Kazazian, Jr., J. D. Boeke, and A. Gabriel, Science 254:1808-1810, 1991). Because L1 elements are so numerous, efficient methods for identifying active copies are required. We have developed a simple in vivo assay for the activity of L1 RT based on the system developed by Derr et al. (Derr, L. K., J. N. Strathern, and D. J. Garfinkel, Cell 67:355-364, 1991) for yeast HIS3 pseudogene formation. L1 ORF2 displays an in vivo RT activity similar to that of yeast Ty1 RT in this system and generates pseudogenes with unusual structures. Like the HIS3 pseudogenes whose formation depends on Ty1 RT, the HIS3 pseudogenes generated by L1 RT are joined to Ty1 sequences and often are part of complex arrays of Ty1 elements, multiple HIS3 pseudogenes, and hybrid Ty1/L1 elements. These pseudogenes differ from those previously described in that there are base pairs of unknown origin inserted at several of the junctions. In two of three HIS3 pseudogenes studied, the L1 RT appears to have jumped from the 5' end of a Ty1/L1 transcript to the poly(A) tract of the HIS3 RNA.

scholarly journals Complete Genome Sequence of Yersinia pestis Strains Antiqua and Nepal516: Evidence of Gene Reduction in an Emerging Pathogen

2006 ◽  
Vol 188 (12) ◽  
pp. 4453-4463 ◽  
Author(s):  
Patrick S. G. Chain ◽  
Ping Hu ◽  
Stephanie A. Malfatti ◽  
Lyndsay Radnedge ◽  
Frank Larimer ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Yersinia Pestis ◽  
Yersinia Pseudotuberculosis ◽  
Open Reading Frames ◽  
Genomic Diversity ◽  
Avirulent Strain ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Protein Coding ◽  
Definition Of

ABSTRACT Yersinia pestis, the causative agent of bubonic and pneumonic plagues, has undergone detailed study at the molecular level. To further investigate the genomic diversity among this group and to help characterize lineages of the plague organism that have no sequenced members, we present here the genomes of two isolates of the “classical” antiqua biovar, strains Antiqua and Nepal516. The genomes of Antiqua and Nepal516 are 4.7 Mb and 4.5 Mb and encode 4,138 and 3,956 open reading frames, respectively. Though both strains belong to one of the three classical biovars, they represent separate lineages defined by recent phylogenetic studies. We compare all five currently sequenced Y. pestis genomes and the corresponding features in Yersinia pseudotuberculosis. There are strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms, and a unique distribution of insertion sequences. We found 453 single nucleotide polymorphisms in protein-coding regions, which were used to assess the evolutionary relationships of these Y. pestis strains. Gene reduction analysis revealed that the gene deletion processes are under selective pressure, and many of the inactivations are probably related to the organism's interaction with its host environment. The results presented here clearly demonstrate the differences between the two biovar antiqua lineages and support the notion that grouping Y. pestis strains based strictly on the classical definition of biovars (predicated upon two biochemical assays) does not accurately reflect the phylogenetic relationships within this species. A comparison of four virulent Y. pestis strains with the human-avirulent strain 91001 provides further insight into the genetic basis of virulence to humans.

Association Between Two Single-nucleotide Polymorphism of TAAR1 Gene and Suicide Attempts

2017 ◽  
Vol 41 (S1) ◽  
pp. S103-S103
Author(s):  
A. Zdanowicz ◽  
A. Sakowicz ◽  
E. Kusidel ◽  
P. Wierzbinski
Keyword(s):  
Suicide Attempts ◽  
Statistical Tests ◽  
Control Group ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Hardy Weinberg Equilibrium ◽  
The Mean ◽  
Competing Interest ◽  
G Protein Coupled ◽  
The Brain

IntroductionTAAR1 is a G protein-coupled receptor expressed broadly throughout the brain. Recently, TAAR1 has been demonstrated to be an important modulator of the dopaminergic, serotonergic and glutamatergic activity.AimsAssessment of the relation between two single-nucleotide polymorphisms of TAAR1 gene, suicide attempts and alcohol abuse.MethodsA total of 150 Polish patients were included, 59 subjects after suicide attempt vs. 91 controls. The chosen SNPs (rs759733834 and rs9402439) were studied using RFLP-PCR methods. The Hardy-Weinberg equilibrium was tested in control group.Statistical testsChi2 or Yeates Chi2 Test were used.ResultsThe mean age of study subjects and controls was: 38 ± 12.3 and 42 ± 12.8 respectively; 49% study males vs. 54% male controls. We did not observe the association between the carriage of the genotypes GG, GA and AA of rs759733834 polymorphisms in either of the groups. The distribution of genotypes in respect to rs9402439 polymorphism (CC, CG, GG) was also insignificant. Among patients with alcohol dependence, the frequency G allele of rs9402439 polymorphism was lower compared to non-addicted ones (27 vs. 47%) P < 0.01.ConclusionsTAAR1 polymorphisms rs759733834 and rs9402439 are not related to suicide attempts. The carriage of allele G of rs9402439 polymorphism is related to lower risk of alcohol addiction OR 0.40 95%Cl 0.20–0.81. To our knowledge, this is the first study on the TAAR1 receptor and the risk of suicide and it might offer a new insight into genetic etiology of TAAR1 receptor.Disclosure of interestThe authors have not supplied their declaration of competing interest.

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