scholarly journals El uso de secuencias génicas para estudios taxonómicos

2017 ◽  
pp. 137
Author(s):  
Dolores González
Keyword(s):  
Dna Sequences ◽  
Cladistic Analysis ◽  
Nuclear Genome ◽  
Restriction Enzymes ◽  
Dna Variation ◽  
Transfer Rnas ◽  
Taxonomic Research ◽  
Sampling Procedures ◽  
Rna Genes ◽  
Molecular Characters

During the last years, the use of molecular characters for taxonomic research has increased notably. Characters most commonly used come from restriction enzymes and sequencing of genes or particular DNA regions. Sequences present potential advantages over other molecular characters. This paper describes sampling procedures to detect DNA variation through sequencing. Among procedures for DNA sequencing, enzymatic methods are of generalized application, and the tendency is toward the use of non-radioactive markers and automated sequencing. A brief introduction to the different stages of cladistic analysis is also included, especially those required for DNA sequences. A revision of genes used in systematics is provided. The most common are the nuclear, mitochondrial and chloroplast ribosomal RNA genes, and the rbcL from chloroplast. Other genes under investigation are the globins and the alcohol dehydrogenase (from the nuclear genome), the cytochrome b and the transfer RNAs (from the mitochondrial genome), and the "matK" and the "rpo" (from the chloroplast genome).

scholarly journals Variability of the genome size in coniferous plant in extreme environmental conditions

1970 ◽  
pp. 37-41
Author(s):  
T. S. Sedelnikova
Keyword(s):  
Genome Size ◽  
Repetitive Dna ◽  
Dna Sequences ◽  
Environmental Conditions ◽  
Nuclear Dna ◽  
Chromosomal Rearrangements ◽  
Repetitive Dna Sequences ◽  
Dna Variation ◽  
Nuclear Dna Variation ◽  
Rna Genes

Aim. The features of genome size transformation in conifers growing in extreme environmental conditions are reviewed. Conclusions. Conifers have a very large genome. The main resources of genome size modifications of conifers under extreme environmental conditions are: variability of the chromosome numbers (polyploidy, aneuploidy; mixoploidy), occurrence of B-chromosomes and increasing of its numbers, changes of the content of nuclear DNA, variation of the repetitive DNA sequences (microsatellites, ribosomal RNA genes, transposable elements – retrotransposons), and the chromosomal rearrangements. These features are also components of the epigenetic system which defines the adaptability of the genome changes when exposed to stressful environmental factors. Keywords: Pinophyta, genome, repetitive DNA sequences, epigenetic system.

scholarly journals Chromosomal assembly of the nuclear genome of the endosymbiont-bearing trypanosomatid Angomonas deanei

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
John W Davey ◽  
Carolina M C Catta-Preta ◽  
Sally James ◽  
Sarah Forrester ◽  
Maria Cristina M Motta ◽  
...  
Keyword(s):  
Chromosome Number ◽  
Noncoding Rnas ◽  
Nuclear Genome ◽  
Supernumerary Chromosome ◽  
Ribosomal Rnas ◽  
Protein Coding ◽  
Transfer Rnas ◽  
Protein Coding Genes ◽  
Oxford Nanopore ◽  
Genome Assemblies

Abstract Angomonas deanei is an endosymbiont-bearing trypanosomatid with several highly fragmented genome assemblies and unknown chromosome number. We present an assembly of the A. deanei nuclear genome based on Oxford Nanopore sequence that resolves into 29 complete or close-to-complete chromosomes. The assembly has several previously unknown special features; it has a supernumerary chromosome, a chromosome with a 340-kb inversion, and there is a translocation between two chromosomes. We also present an updated annotation of the chromosomal genome with 10,365 protein-coding genes, 59 transfer RNAs, 26 ribosomal RNAs, and 62 noncoding RNAs.

Evolution of the chloroplast genome and polymorphic ITS regions in Allium subg. Melanocrommyum

Genome ◽  
1999 ◽  
Vol 42 (2) ◽  
pp. 237-247 ◽  
Author(s):  
Ted HM Mes ◽  
Reinhard M Fritsch ◽  
Sven Pollner ◽  
Konrad Bachmann
Keyword(s):  
Concerted Evolution ◽  
Morphological Evolution ◽  
Restriction Analysis ◽  
Nuclear Genome ◽  
Restriction Enzymes ◽  
Border Region ◽  
Chloroplast Genomes ◽  
Central Asian ◽  
Its Regions ◽  
Chloroplast Haplotypes

Relationships based on PCR-RFLPs of non-coding regions of cpDNA indicate that some of the largest subgenera of the genus Allium and five of the largest sections of the Central Asian subg. Melanocrommyum are artificial. Internested synapomorphic mutations without homoplasy were found only in the chloroplast genomes of plants of subg. Melanocrommyum that occur in the border region of Tajikistan, Uzbekistan, Afghanistan, and Kyrgyzstan. Eighteen of 49 plants surveyed were polymorphic for their ITS regions. Even plants that had identical chloroplast genomes were polymorphic for nuclear ribosomal regions. These individuals had markedly different frequencies of ITS variants that were detected with various restriction enzymes. The geographic partitioning of chloroplast haplotypes and the fact that the ITS variants could not be ordered hierarchically can readily be envisioned to result from gene flow. Processes such as concerted evolution and parallel morphological evolution may also be partly responsible for the disconcordance of mutations in the chloroplast and nuclear genome. However, the chimeric nature of the nuclear ribosomal regions indicates that concerted evolution is not the dominating process in Allium subg. Melanocrommyum.Key words: polymorphic, phylogeny, restriction analysis.

Mitochondrial and nuclear DNA variation, genotype fingerprinting and genetic relationships in lentil (Lens culinaris Medik.)

1997 ◽  
Vol 77 (4) ◽  
pp. 515-521 ◽  
Author(s):  
Om P. Rajora ◽  
John D. Mahon
Keyword(s):  
Mitochondrial Dna ◽  
Restriction Fragment ◽  
Lens Culinaris ◽  
Nuclear Dna ◽  
Genetic Relationships ◽  
Restriction Enzymes ◽  
Dna Variation ◽  
Apocytochrome B ◽  
Nuclear Dna Variation ◽  
Mean Similarity

Mitochondrial DNA (mtDNA) and nuclear DNA (nuDNA) variations were examined in six cultivars of Lens culinaris ssp. culinaris and two (mtDNA) or one (nuDNA) accession(s) of L. culinaris ssp. orientalis. Total leaf DNA was digested with up to 15 restriction endonucleases, separated by agarose gel electrophoresis and trasferred to nylon membranes. To examine mtDNA variation, blots were probed with mtDNA coding for cytochrome c oxidase I (coxI) and ATPase 6 (atp6) of both wheat and maize as well as apocytochrome b (cob) and Orf25 (orf25) of wheat. Sixteen combinations of mtDNA probes and restriction enzymes revealed 34 fragments that discriminated between at least two lentil accessions. For nuDNA analysis, probes from cDNA and genomic DNA clones of lentil were used to probe the same blots, and identified 46 diagnostic fragments from 19 probe/enzyme combinations. Each lentil accession could be unequivocably distinguished from all others on the basis of both mitochondrial and nuclear DNA fragment patterns. The mitochondrial restriction fragment similarities ranged from 0.944 to 0.989, with a mean of 0.970 but nuclear restriction fragment similarities varied from 0.582 to 0.987, with a mean of 0.743. The apparent genetic relationships among accessions differed according to the source of DNA examined, although the commercial varieties Laird, Brewer and Redchief showed similarly high levels of mean similarity with both nuclear (0.982) and mitochondrial DNA (0.983). Key words: Lens culinaris Medik., genetic variation, mitochondrial, nuclear, DNA, lentil

CLASSIFICATION AND IDENTIFICATION OF FUNGAL SEQUENCES USING CHARACTERISTIC RESTRICTION ENDONUCLEASE CUT ORDER

2010 ◽  
Vol 08 (02) ◽  
pp. 181-198 ◽  
Author(s):  
RAJIB SENGUPTA ◽  
DHUNDY R. BASTOLA ◽  
HESHAM H. ALI
Keyword(s):  
Dna Sequences ◽  
Restriction Enzymes ◽  
Epidemiological Studies ◽  
Global Alignment ◽  
Target Sequence ◽  
Alignment Algorithm ◽  
Molecular Fingerprinting ◽  
Data Set ◽  
Alignment Free ◽  
Wet Lab

Restriction Fragment Length Polymorphism (RFLP) is a powerful molecular tool that is extensively used in the molecular fingerprinting and epidemiological studies of microorganisms. In a wet-lab setting, the DNA is cut with one or more restriction enzymes and subjected to gel electrophoresis to obtain signature fragment patterns, which is utilized in the classification and identification of organisms. This wet-lab approach may not be practical when the experimental data set includes a large number of genetic sequences and a wide pool of restriction enzymes to choose from. In this study, we introduce a novel concept of Enzyme Cut Order — a biological property-based characteristic of DNA sequences which can be defined and analyzed computationally without any alignment algorithm. In this alignment-free approach, a similarity matrix is developed based on the pairwise Longest Common Subsequences (LCS) of the Enzyme Cut Orders. The choice of an ideal set of restriction enzymes used for analysis is augmented by using genetic algorithms. The results obtained from this approach using internal transcribed spacer regions of rDNA from fungi as the target sequence show that the phylogenetically-related organisms form a single cluster and successful grouping of phylogenetically close or distant organisms is dependent on the choice of restriction enzymes used in the analysis. Additionally, comparison of trees obtained with this alignment-free and the legacy method revealed highly similar tree topologies. This novel alignment-free method, which utilizes the Enzyme Cut Order and restriction enzyme profile, is a reliable alternative to local or global alignment-based classification and identification of organisms.

scholarly journals Genome-Wide Identification of 5-Methylcytosine Sites in Bacterial Genomes By High-Throughput Sequencing of MspJI Restriction Fragments

2021 ◽  
Author(s):  
Brian P. Anton ◽  
Alexey Fomenkov ◽  
Victoria Wu ◽  
Richard J. Roberts
Keyword(s):  
Single Molecule ◽  
Dna Sequences ◽  
High Throughput Sequencing ◽  
Cost Effective ◽  
Restriction Enzymes ◽  
Specific Sequence ◽  
Genome Wide ◽  
Cost Effective Alternative ◽  
Simple Column ◽  
Sequencing Platforms

ABSTRACTSingle-molecule Real-Time (SMRT) sequencing can easily identify sites of N6-methyladenine and N4-methylcytosine within DNA sequences, but similar identification of 5-methylcytosine sites is not as straightforward. In prokaryotic DNA, methylation typically occurs within specific sequence contexts, or motifs, that are a property of the methyltransferases that “write” these epigenetic marks. We present here a straightforward, cost-effective alternative to both SMRT and bisulfite sequencing for the determination of prokaryotic 5-methylcytosine methylation motifs. The method, called MFRE-Seq, relies on excision and isolation of fully methylated fragments of predictable size using MspJI-Family Restriction Enzymes (MFREs), which depend on the presence of 5-methylcytosine for cleavage. We demonstrate that MFRE-Seq is compatible with both Illumina and Ion Torrent sequencing platforms and requires only a digestion step and simple column purification of size-selected digest fragments prior to standard library preparation procedures. We applied MFRE-Seq to numerous bacterial and archaeal genomic DNA preparations and successfully confirmed known motifs and identified novel ones. This method should be a useful complement to existing methodologies for studying prokaryotic methylomes and characterizing the contributing methyltransferases.

scholarly journals Genome-wide identification of 5-methylcytosine sites in bacterial genomes by high-throughput sequencing of MspJI restriction fragments

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0247541
Author(s):  
Brian P. Anton ◽  
Alexey Fomenkov ◽  
Victoria Wu ◽  
Richard J. Roberts
Keyword(s):  
Single Molecule ◽  
Dna Sequences ◽  
High Throughput Sequencing ◽  
Cost Effective ◽  
Restriction Enzymes ◽  
Specific Sequence ◽  
Genome Wide ◽  
Cost Effective Alternative ◽  
Simple Column ◽  
Sequencing Platforms

Single-molecule Real-Time (SMRT) sequencing can easily identify sites of N6-methyladenine and N4-methylcytosine within DNA sequences, but similar identification of 5-methylcytosine sites is not as straightforward. In prokaryotic DNA, methylation typically occurs within specific sequence contexts, or motifs, that are a property of the methyltransferases that “write” these epigenetic marks. We present here a straightforward, cost-effective alternative to both SMRT and bisulfite sequencing for the determination of prokaryotic 5-methylcytosine methylation motifs. The method, called MFRE-Seq, relies on excision and isolation of fully methylated fragments of predictable size using MspJI-Family Restriction Enzymes (MFREs), which depend on the presence of 5-methylcytosine for cleavage. We demonstrate that MFRE-Seq is compatible with both Illumina and Ion Torrent sequencing platforms and requires only a digestion step and simple column purification of size-selected digest fragments prior to standard library preparation procedures. We applied MFRE-Seq to numerous bacterial and archaeal genomic DNA preparations and successfully confirmed known motifs and identified novel ones. This method should be a useful complement to existing methodologies for studying prokaryotic methylomes and characterizing the contributing methyltransferases.

scholarly journals Automata for DNA Splicing Languages with Palindromic and Non-Palindromic Restriction Enzymes using Grammars

MATEMATIKA ◽  
2019 ◽  
Vol 35 (4) ◽  
pp. 1-14
Author(s):  
Wan Heng Fong ◽  
Nurul Izzaty Ismail ◽  
Nor Haniza Sarmin
Keyword(s):  
Dna Sequences ◽  
Formal Language ◽  
Restriction Enzymes ◽  
Language Theory ◽  
Dna Assembly ◽  
Dna Molecules ◽  
Splicing Systems ◽  
Transition Graphs ◽  
Palindromic Sequences ◽  
Dna Splicing

In DNA splicing system, DNA molecules are cut and recombined with the presence of restriction enzymes and a ligase. The splicing system is analyzed via formal language theory where the molecules resulting from the splicing system generate a language which is called a splicing language. In nature, DNA molecules can be read in two ways; forward and backward. A sequence of string that reads the same forward and backward is known as a palindrome. Palindromic and non-palindromic sequences can also be recognized in restriction enzymes. Research on splicing languages from DNA splicing systems with palindromic and non-palindromic restriction enzymes have been done previously. This research is motivated by the problem of DNA assembly to read millions of long DNA sequences where the concepts of automata and grammars are applied in DNA splicing systems to simplify the assembly in short-read sequences. The splicing languages generated from DNA splicing systems with palindromic and nonpalindromic restriction enzymes are deduced from the grammars which are visualised as automata diagrams, and presented by transition graphs where transition labels represent the language of DNA molecules resulting from the respective DNA splicing systems.

Genetic Disease and Therapy

2021 ◽  
Vol 16 (1) ◽  
pp. 145-166
Author(s):  
Theodore L. Roth ◽  
Alexander Marson
Keyword(s):  
Dna Sequences ◽  
Current Practice ◽  
Genetic Diseases ◽  
Genetic Material ◽  
Nuclear Genome ◽  
Genetic Alterations ◽  
Genetic Diagnostics ◽  
Gene Therapies ◽  
Disease Risks ◽  
Diagnosis Therapy

Genetic diseases cause numerous complex and intractable pathologies. DNA sequences encoding each human's complexity and many disease risks are contained in the mitochondrial genome, nuclear genome, and microbial metagenome. Diagnosis of these diseases has unified around applications of next-generation DNA sequencing. However, translating specific genetic diagnoses into targeted genetic therapies remains a central goal. To date, genetic therapies have fallen into three broad categories: bulk replacement of affected genetic compartments with a new exogenous genome, nontargeted addition of exogenous genetic material to compensate for genetic errors, and most recently, direct correction of causative genetic alterations using gene editing. Generalized methods of diagnosis, therapy, and reagent delivery into each genetic compartment will accelerate the next generations of curative genetic therapies. We discuss the structure and variability of the mitochondrial, nuclear, and microbial metagenomic compartments, as well as the historical development and current practice of genetic diagnostics and gene therapies targeting each compartment.

Sign in / Sign up

Export Citation Format

Share Document