Isolation of a yeast gene involved in species-specific pre-tRNA processing.

To identify genes involved in pre-tRNA processing, we searched for yeast DNA sequences that specifically enhanced the expression of the SUP4(G37) gene. The SUP4(G37) gene possesses a point mutation at position 37 of suppressor tRNA(Tyr). This lesion results in a reduced rate of pre-tRNA splicing and a decreased level of nonsense suppression. A SUP4(G37) strain was transformed with a yeast genomic library, and the transformants were screened for increased suppressor activity. One transformant contained a plasmid that encoded an unessential gene, STP1, that in multiple copies enhanced the suppression of SUP4(G37) and caused increased production of mature SUP4(G37) product. Disruption of the genomic copy of STP1 resulted in a reduced efficiency of SUP4-mediated suppression and the accumulation of pre-tRNAs. Not all intron-containing pre-tRNAs were affected by the stp1-disruption. At least five of the nine families of pre-tRNAs were affected. Two other species, pre-tRNA(Ile) and pre-tRNA(3Leu), were not. We propose that STP1 encodes a tRNA species-specific product that functions as a helper for pre-tRNA splicing. The STP1 product may interact with pre-tRNAs to generate a structure that is efficiently recognized by splicing machinery.

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A species-specific oligonucleotide DNA probe for the identification of Meloidogyne incognita

Parasitology ◽

10.1017/s003118200005959x ◽

1991 ◽

Vol 103 (2) ◽

pp. 315-319 ◽

Cited By ~ 4

Author(s):

M. R. Chacon ◽

R. M. E. Parkhouse ◽

M. P. Robinson ◽

P. R. Burrows ◽

T. Garate

Keyword(s):

Dna Sequences ◽

Diagnostic Tool ◽

Meloidogyne Incognita ◽

Genomic Dna ◽

Genomic Library ◽

Dna Probe ◽

Equal Length ◽

Race 1 ◽

Species Specific

A genomic library of Meloidogyne incognita Race 1 has been prepared in the bacteriophage λgt10 and screened for specific DNA sequences by hybridization with radio-isotope labelled total genomic DNA from a number of Meloidogyne species. One clone isolated (MR1#15), although not totally species specific, clearly showed preferential hybridization to M. incognita. Following subcloning and sequencing of the 255 bp insert, four stretches of the sequence corresponding to oligonucleotides of approximately equal length (~60 bp) were synthesized and examined for specificity. One of them, MR1#15.2, showed the necessary specificity to be used as a diagnostic tool.

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Codon harmonization reduces amino acid misincorporation in bacterially expressed P. falciparum proteins and improves their immunogenicity

AMB Express ◽

10.1186/s13568-019-0890-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Neeraja Punde ◽

Jennifer Kooken ◽

Dagmar Leary ◽

Patricia M. Legler ◽

Evelina Angov

Keyword(s):

Protein Structure ◽

Amino Acid ◽

Codon Usage ◽

Dna Sequences ◽

Structural Integrity ◽

Host Cells ◽

Loss Of Function ◽

Species Specific ◽

And Function ◽

The Impact

Abstract Codon usage frequency influences protein structure and function. The frequency with which codons are used potentially impacts primary, secondary and tertiary protein structure. Poor expression, loss of function, insolubility, or truncation can result from species-specific differences in codon usage. “Codon harmonization” more closely aligns native codon usage frequencies with those of the expression host particularly within putative inter-domain segments where slower rates of translation may play a role in protein folding. Heterologous expression of Plasmodium falciparum genes in Escherichia coli has been a challenge due to their AT-rich codon bias and the highly repetitive DNA sequences. Here, codon harmonization was applied to the malarial antigen, CelTOS (Cell-traversal protein for ookinetes and sporozoites). CelTOS is a highly conserved P. falciparum protein involved in cellular traversal through mosquito and vertebrate host cells. It reversibly refolds after thermal denaturation making it a desirable malarial vaccine candidate. Protein expressed in E. coli from a codon harmonized sequence of P. falciparum CelTOS (CH-PfCelTOS) was compared with protein expressed from the native codon sequence (N-PfCelTOS) to assess the impact of codon usage on protein expression levels, solubility, yield, stability, structural integrity, recognition with CelTOS-specific mAbs and immunogenicity in mice. While the translated proteins were expected to be identical, the translated products produced from the codon-harmonized sequence differed in helical content and showed a smaller distribution of polypeptides in mass spectra indicating lower heterogeneity of the codon harmonized version and fewer amino acid misincorporations. Substitutions of hydrophobic-to-hydrophobic amino acid were observed more commonly than any other. CH-PfCelTOS induced significantly higher antibody levels compared with N-PfCelTOS; however, no significant differences in either IFN-γ or IL-4 cellular responses were detected between the two antigens.

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Species-diagnostic and species-specific DNA sequences evenly distributed throughout pine and spruce chromosomes

Genome ◽

10.1139/g10-065 ◽

2010 ◽

Vol 53 (10) ◽

pp. 769-777 ◽

Cited By ~ 1

Author(s):

Melanie Mehes-Smith ◽

Paul Michael ◽

Kabwe Nkongolo

Keyword(s):

Dna Sequences ◽

Random Amplified Polymorphic Dna ◽

Inter Simple Sequence Repeat ◽

Issr Markers ◽

Pinus Monticola ◽

The Family ◽

Species Specific ◽

Rapd And Issr ◽

Specific Sequences

Genome organization in the family Pinaceae is complex and largely unknown. The main purpose of the present study was to develop and physically map species-diagnostic and species-specific molecular markers in pine and spruce. Five RAPD (random amplified polymorphic DNA) and one ISSR (inter-simple sequence repeat) species-diagnostic or species-specific markers for Picea mariana , Picea rubens , Pinus strobus , or Pinus monticola were identified, cloned, and sequenced. In situ hybridization of these sequences to spruce and pine chromosomes showed the sequences to be present in high copy number and evenly distributed throughout the genome. The analysis of centromeric and telomeric regions revealed the absence of significant clustering of species-diagnostic and species-specific sequences in all the chromosomes of the four species studied. Both RAPD and ISSR markers showed similar patterns.

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Retention of relict satellite DNA sequences in Anemone (Ranunculaceae)

Acta Botanica Croatica ◽

10.2478/v10184-012-0010-z ◽

2013 ◽

Vol 72 (1) ◽

pp. 1-133 ◽

Cited By ~ 2

Author(s):

Višnja Besendorfer ◽

Jelena Mlinarec

Keyword(s):

Dna Sequences ◽

Southern Hybridization ◽

Repeat Unit ◽

Similar Species ◽

Genomic Component ◽

Library Hypothesis ◽

Species Specific ◽

Eukaryotic Organisms ◽

Fish Signal

Abstract Satellite DNAis a genomic component present in virtually all eukaryotic organisms. The turnover of highly repetitive satellite DNAis an important element in genome organization and evolution in plants. Here we study the presence, physical distribution and abundance of the satellite DNAfamily AhTR1 in Anemone. Twenty-two Anemone accessions were analyzed by PCR to assess the presence of AhTR1, while fluorescence in situ hybridization and Southern hybridization were used to determine the abundance and genomic distribution of AhTR1. The AhTR1 repeat unit was PCR-amplified only in eight phylogenetically related European Anemone taxa of the Anemone section. FISH signal with AhTR1 probe was visible only in A. hortensis and A. pavonina, showing localization of AhTR1 in the regions of interstitial heterochromatin in both species. The absence of a FISH signal in the six other taxa as well as weak signal after Southern hybridization suggest that in these species AhTR1 family appears as relict sequences. Thus, the data presented here support the »library hypothesis« for AhTR1 satellite evolution in Anemone. Similar species-specific satellite DNAprofiles in A. hortensis and A. pavonina support the treatment of A. hortensis and A. pavonina as one species, i.e. A. hortensis s.l.

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Effect of intron mutations on processing and function of Saccharomyces cerevisiae SUP53 tRNA in vitro and in vivo.

Molecular and Cellular Biology ◽

10.1128/mcb.6.7.2663 ◽

1986 ◽

Vol 6 (7) ◽

pp. 2663-2673 ◽

Cited By ~ 49

Author(s):

M C Strobel ◽

J Abelson

Keyword(s):

Saccharomyces Cerevisiae ◽

Trna Gene ◽

Nuclear Extract ◽

Nonsense Suppression ◽

Trna Genes ◽

Suppressor Activity ◽

Specific Sequence ◽

Made In

The Saccharomyces cerevisiae leucine-inserting amber suppressor tRNA gene SUP53 (a tRNALeu3 allele) was used to investigate the relationship between precursor tRNA structure and mature tRNA function. This gene encodes a pre-tRNA which contains a 32-base intron. The mature tRNASUP53 contains a 5-methylcytosine modification of the anticodon wobble base. Mutations were made in the SUP53 intron. These mutant genes were transcribed in an S. cerevisiae nuclear extract preparation. In this extract, primary tRNA gene transcripts are end-processed and base modified after addition of cofactors. The base modifications made in vitro were examined, and the mutant pre-tRNAs were analyzed for their ability to serve as substrates for partially purified S. cerevisiae tRNA endonuclease and ligase. Finally, the suppressor function of these mutant tRNA genes was assayed after their integration into the S. cerevisiae genome. Mutant analysis showed that the totally intact precursor tRNA, rather than any specific sequence or structure of the intron, was necessary for efficient nonsense suppression by tRNASUP53. Less efficient suppressor activity correlated with the absence of the 5-methylcytosine modification. Most of the intron-altered precursor tRNAs were successfully spliced in vitro, indicating that modifications are not critical for recognition by the tRNA endonuclease and ligase.

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Species-specific duplex PCR for the detection of Pratylenchus penetrans

Nematology ◽

10.1163/156854109x428016 ◽

2009 ◽

Vol 11 (6) ◽

pp. 847-857 ◽

Cited By ~ 21

Author(s):

Lieven Waeyenberge ◽

Nicole Viaene ◽

Maurice Moens

Keyword(s):

Internal Control ◽

Dna Sequences ◽

Rrna Gene ◽

Duplex Pcr ◽

Specific Primers ◽

5.8S Rrna Gene ◽

5.8S Rrna ◽

Wide Range ◽

Pcr Products ◽

Species Specific

Abstract ITS1, the 5.8S rRNA gene and ITS2 of the rDNA region were sequenced from 20 different Pratylenchus species. Additionally, the same region was sequenced from seven populations of P. penetrans. After purifying, cloning and sequencing the PCR products, all sequences were aligned in order to find unique sites suitable for the design of species-specific primers for P. penetrans. Since ITS regions showed variability between and even within populations of P. penetrans, only three small DNA sequences were suitable for the construction of three potentially useful species-specific primers. New species-specific primers were paired with existing universal ITS primers and tested in all possible primer combinations. The best performing primer set, supplemented with a universal 28S rDNA primer set that served as an internal control, was tested in duplex PCR. The ideal annealing temperature, Mg2+ concentration and primer ratios were then determined for the most promising primer set. The optimised duplex PCR was subsequently tested on a wide range of different Pratylenchus spp. and 25 P. penetrans populations originating from all over the world. To test the sensitivity, the duplex PCR was conducted on DNA extracted from a single P. penetrans nematode mixed with varying amounts of nematodes belonging to another Pratylenchus species. Results showed that a reliable and sensitive P. penetrans species-specific duplex PCR was constructed.

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Species specific DNA sequences in the Triticeae

Hereditas ◽

10.1111/j.1601-5223.1992.tb00204.x ◽

1992 ◽

Vol 116 (1-2) ◽

pp. 49-54 ◽

Cited By ~ 13

Author(s):

K. ANAMTHAWAT-JÓNSSON ◽

J. S. HESLOP-HARRISON

Keyword(s):

Dna Sequences ◽

Species Specific

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Quantitative Detection of Species-Specific DNA in Feedstuffs and Fish Meals

Journal of Food Protection ◽

10.4315/0362-028x-68.6.1217 ◽

2005 ◽

Vol 68 (6) ◽

pp. 1217-1221 ◽

Cited By ~ 27

Author(s):

PAVEL KRCMAR ◽

EVA RENCOVA

Keyword(s):

Mitochondrial Dna ◽

Real Time ◽

Dna Sequences ◽

Real Time Pcr ◽

Single Species ◽

Absolute Quantification ◽

Quantitative Detection ◽

Vertebrate Species ◽

Target Species ◽

Species Specific

A sensitive and rapid method for the quantitative detection of bovine-, ovine-, swine-, and chicken-specific mitochondrial DNA sequences based on real-time PCR has been developed. The specificity of the primers and probes for real-time PCR has been tested using DNA samples of other vertebrate species that may also be present in rendered products. The quantitative detection was performed with dual-labeled probes (TaqMan) using absolute quantification with external standards of single species meat-and-bone meals. This method facilitates the detection of 0.01% of the target species–derived material in concentrate feed mixtures and fish meals.

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Development and Application of a New PCR Method for Detection of Blumeria graminis f. sp. tritici

Journal of Molecular Microbiology and Biotechnology ◽

10.1159/000494432 ◽

2018 ◽

Vol 28 (3) ◽

pp. 137-146 ◽

Cited By ~ 1

Author(s):

Adam Kuzdraliński ◽

Hubert Szczerba ◽

Anna Kot ◽

Agnieszka Ostrowska ◽

Michał Nowak ◽

...

Keyword(s):

Dna Sequences ◽

Puccinia Triticina ◽

Blumeria Graminis ◽

Pyrenophora Tritici Repentis ◽

Field Samples ◽

Expected Length ◽

Pcr Assays ◽

Primer Sets ◽

Wheat Leaves ◽

Species Specific

We developed new PCR assays that target beta-tubulin (TUB2) and 14 alpha-demethylase (CYP51) genes and used them for the species-specific detection of Blumeria graminis f. sp. tritici (Bgt). Based on fungi DNA sequences available in the NCBI (National Center for Biotechnology Information) GenBank database we developed simplex and duplex PCR assays. The specificities of the primer sets were evaluated using environmental samples of wheat leaves collected during the 2015/2016 growing season across Poland. Primer sets LidBg17/18 and LidBg21/22 strongly amplified fragments of the expected length for all 67 tested samples. Primer specificity was confirmed using field samples of Zymoseptoria tritici, Puccinia triticina (syn. P. recondita f. sp. tritici), P. striiformis f. sp. tritici, and Pyrenophora tritici-repentis.

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