Ribosomal DNA variation in the grasshopper, Dichroplus elongatus

Genome ◽  
2002 ◽  
Vol 45 (6) ◽  
pp. 1125-1133 ◽  
Author(s):  
M Clemente ◽  
M I Remis ◽  
J C Vilardi
Keyword(s):  
Ribosomal Dna ◽  
Fragment Size ◽  
Natural Populations ◽  
Size Variation ◽  
Rflp Analysis ◽  
Restriction Enzymes ◽  
Genetic Distances ◽  
Climatic Variables ◽  
Dna Variation ◽  
And Migration

We report an RFLP analysis of ribosomal DNA variation in natural populations of the grasshopper, Dichroplus elongatus, previously analyzed for mitochondrial DNA variation. DNA samples were digested with five restriction enzymes, BamHI, EcoRI, HindIII, PstI, andXbaI.BamHI was the only enzyme that showed no variation. The remaining enzymes showed fragment size variation at both intra- and interpopulation levels. Stepwise regression analysis revealed that the average number of length variants per individual is significantly associated with altitude. Moreover, the same analysis indicated that the frequency of some restriction variants exhibits a significant regression on both geographic and climatic variables. The intra- and interpopulation variability of rDNA was analysed by Lynch's and Hedrick's similarity indices using presence or absence of a fragment and band intensities, respectively. The corresponding neighbour-joining (N-J) trees based on Lynch's and Hedrick's genetic distances resulted in similar topologies. However, these trees were not in agreement with the N-J dendrogram obtained from mtDNA data previously reported by Clemente et al. (2000). The disagreement between mtDNA and rDNA phenograms along with the observed correlation between rDNA variability and geographical and climatic variables suggest some form of selection, besides genetic drift and migration, is involved in the pattern of rDNA variation.Key words: Dichroplus elongatus, ribosomal DNA, RFLP, environmental variables.

Mitochondrial and ribosomal DNA variation among members of the Anopheles quadrimaculatus (Diptera: Culicidae) species complex

Genome ◽  
1992 ◽  
Vol 35 (6) ◽  
pp. 939-950 ◽  
Author(s):  
Sharon E. Mitchell ◽  
Sudhir K. Narang ◽  
Andrew F. Cockburn ◽  
J. A. Seawright ◽  
Michael Goldenthal
Keyword(s):  
Mitochondrial Dna ◽  
Ribosomal Dna ◽  
Sibling Species ◽  
Species Complex ◽  
Restriction Enzymes ◽  
Dna Variation ◽  
Restriction Patterns ◽  
Genetic Structure Of Populations ◽  
Anopheles Quadrimaculatus ◽  
Species Specific

The extent of intra- and inter-specific variation in mitochondrial DNA and nuclear ribosomal RNA gene restriction sites was determined for the four sibling species of the Anopheles quadrimaculatus complex. Individual mosquitoes were identified by allozyme analysis according to previously published keys, and the total genomic DNA of these same individuals was then cleaved with restriction enzymes. Restriction maps of mitochondrial DNA, including the positions of variable sites, were constructed for each species. No evidence for interspecific hybridization was found in the populations surveyed. There was little variation in restriction patterns within any given species, but differences occurred among the four. Three restriction enzymes (AvaI, HindIII, and PvuII) yielded species-specific DNA restriction patterns for the mitochondrial DNA, while AvaI and HindIII produced diagnostic patterns for the ribosomal DNA. Thus, restriction patterns were very useful for detecting cryptic species but less appropriate than isozymes for studying genetic structure of populations within species.Key words: mtDNA, rDNA, Anopheles quadrimaculatus, species complex, sibling species.

scholarly journals A comprehensive study of genic variation in natural populations of Drosophila melanogaster. IV. Mitochondrial DNA variation and the role of history vs. selection in the genetic structure of geographic populations.

Genetics ◽  
1991 ◽  
Vol 129 (1) ◽  
pp. 103-117
Author(s):  
L R Hale ◽  
R S Singh
Keyword(s):  
Mitochondrial Dna ◽  
Drosophila Melanogaster ◽  
Restriction Site ◽  
Far East ◽  
Natural Populations ◽  
Size Variation ◽  
Restriction Enzymes ◽  
Western Hemisphere ◽  
Small Scale ◽  
Coding Region

Abstract Preliminary studies with restriction fragment length polymorphisms of mitochondrial DNA (mtDNA) in natural populations of Drosophila melanogaster revealed considerable variation in terms of nucleotide sequence and overall size. In this report we present data from more isofemale lines and more restriction enzymes, and explore the utility of the data in inferring a colonization history of this species. Size variation in the noncoding A + T-rich region is particularly plentiful, with size variants occurring in all restriction site haplotypes in all populations. We report here classes of small-scale mobility polymorphisms (apparent range of 20 bp) in specific restriction fragments in the coding region. The variation in one such fragment appears to be generated even more rapidly than in the noncoding region. On the basis of the distribution of restriction site haplotypes, the species range can be divided into three major regions along longitudinal lines: Euro-African populations are the most diverse and are taken to be oldest; Far East populations have a complex distribution of haplotypes; Western Hemisphere populations are the least diverse and are interpreted to be the youngest. The history inferred from mtDNA alone is remarkably similar to one based on several nuclear markers. The mtDNA haplotype distribution is also very different from that of allozymes in these same populations. We interpret this as further evidence that natural selection is still the most parsimonious explanation for the parallel latitudinal allozyme clines in this species.

Mitochondrial DNA variation in the grasshopper Sinipta dalmani: application of long-PCR to the development of a homologous probe

Genome ◽  
2005 ◽  
Vol 48 (6) ◽  
pp. 971-976 ◽  
Author(s):  
S M Pensel ◽  
J C Vilardi ◽  
M I Remis
Keyword(s):  
Mitochondrial Dna ◽  
Nucleotide Diversity ◽  
Natural Populations ◽  
Rflp Analysis ◽  
Universal Primers ◽  
Chromosome Polymorphism ◽  
Genetic Studies ◽  
Dna Variation ◽  
Long Pcr ◽  
Complete Mtdna

RFLP analysis of mtDNA in natural populations is a valuable tool for phylogeographic and population genetic studies. The amplification of long DNA fragments using universal primers may contribute to the development of novel homologous probes in species for which no previous genomic information is available. Here we report how we obtained the complete mtDNA genome of Sinipta dalmani (Orthoptera) in 2 fragments (7 and 9 kb) using primers of conserved regions. The specificity of the PCR reactions was ultimately confirmed by several lines of evidence. These fragments were used as a probe for a mtDNA RFLP study in S. dalmani that analyzed the pattern of haplotype distribution and nucleotide diversity within and among chromosomally differentiated natural populations. Our results suggest that the restriction in gene flow detected at the molecular level may explain the chromosome differentiation detected previously and the maintenance of chromosome polymorphism in some areas of S. dalmani geographic distribution.Key words: long-PCR, mitochondrial DNA, universal primers, RFLP, grasshopper.

scholarly journals Independent evolution towards larger body size in the distinctive Faroe Island mice

2021 ◽  
Author(s):  
Ricardo Wilches ◽  
William H Beluch ◽  
Ellen McConnell ◽  
Diethard Tautz ◽  
Yingguang Frank Chan
Keyword(s):  
Body Size ◽  
Meta Analysis ◽  
Small Body ◽  
Laboratory Mouse ◽  
Large Body ◽  
Natural Populations ◽  
Size Variation ◽  
Phenotypic Traits ◽  
Island Population ◽  
Multiple Loci

Abstract Most phenotypic traits in nature involve the collective action of many genes. Traits that evolve repeatedly are particularly useful for understanding how selection may act on changing trait values. In mice, large body size has evolved repeatedly on islands and under artificial selection in the laboratory. Identifying the loci and genes involved in this process may shed light on the evolution of complex, polygenic traits. Here, we have mapped the genetic basis of body size variation by making a genetic cross between mice from the Faroe Islands, which are among the largest and most distinctive natural populations of mice in the world, and a laboratory mouse strain selected for small body size, SM/J. Using this F2 intercross of 841 animals, we have identified 111 loci controlling various aspects of body size, weight and growth hormone levels. By comparing against other studies, including the use of a joint meta-analysis, we found that the loci involved in the evolution of large size in the Faroese mice were largely independent from those of a different island population or other laboratory strains. We hypothesize that colonization bottleneck, historical hybridization, or the redundancy between multiple loci have resulted in the Faroese mice achieving an outwardly similar phenotype through a distinct evolutionary path.

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

A new riparian species of Ramalina (Ramalinaceae) from Brazil, with a key to neotropical saxicolous species

2018 ◽  
Vol 50 (5) ◽  
pp. 541-553 ◽  
Author(s):  
Emerson Luiz GUMBOSKI ◽  
Sionara ELIASARO ◽  
Mayara Camila SCUR ◽  
Aline Pedroso LORENZ-LEMKE ◽  
Rosa Mara BORGES DA SILVEIRA
Keyword(s):  
New Species ◽  
Ribosomal Dna ◽  
Habitat Preference ◽  
Molecular Data ◽  
Genetic Distances ◽  
Integrative Approach ◽  
Chemical Variation ◽  
Southern Brazil ◽  
Riparian Species ◽  
High Altitude Grasslands

AbstractThe new species Ramalina fleigiae from Brazil is described growing on rocks in riverbeds in high altitude grasslands of southern Brazil. It grows in areas with constant water flow, sometimes almost immersed, and always in exposed habitats. Through an integrative approach, the detailed description of R. fleigiae includes morphological, anatomical, ecological, chemical and molecular data. Ribosomal DNA-based phylogenies suggest that R. fleigiae is more closely related to a species that shares its habitat preference (R. laevigata) than to the morphologically and chemically similar R. exiguella and R. gracilis. Ramalina fleigiae and R. laevigata can be distinguished by thallus morphology (irregularly flat branches in R. fleigiae vs. flat to canaliculate in R. laevigata) and pattern of chondroid tissue, as genetic distances between them are compatible with the interspecific range. It is possible that many species of Ramalina still remain hidden within the morphological or chemical variation of currently accepted species. Combining ecological, anatomical and molecular data will improve our future understanding of this genus.

scholarly journals Ribosomal DNA Variation within and among Plant Populations

1988 ◽  
Vol 75 (4) ◽  
pp. 1207 ◽  
Author(s):  
Barbara A. Schaal ◽  
Gerald H. Learn
Keyword(s):  
Ribosomal Dna ◽  
Plant Populations ◽  
Dna Variation

Fragment size, pollination efficiency and reproductive success in natural populations of wind-pollinated Polylepis australis (Rosaceae) trees

Flora ◽  
2007 ◽  
Vol 202 (7) ◽  
pp. 547-554 ◽  
Author(s):  
Peggy Seltmann ◽  
Daniel Renison ◽  
Andrea Cocucci ◽  
Isabell Hensen ◽  
Klaus Jung
Keyword(s):  
Reproductive Success ◽  
Fragment Size ◽  
Natural Populations ◽  
Pollination Efficiency ◽  
Polylepis Australis

scholarly journals Genetic structure and gene flow of Eugenia dysenterica natural populations

2005 ◽  
Vol 40 (10) ◽  
pp. 975-980 ◽  
Author(s):  
Maria Imaculada Zucchi ◽  
José Baldin Pinheiro ◽  
Lázaro José Chaves ◽  
Alexandre Siqueira Guedes Coelho ◽  
Mansuêmia Alves Couto ◽  
...  
Keyword(s):  
Gene Flow ◽  
Genetic Variability ◽  
Pearson Correlation ◽  
Natural Populations ◽  
Similarity Index ◽  
Genetic Distances ◽  
Strong Positive Correlation ◽  
Randomly Amplified Polymorphic Dna ◽  
Jaccard Similarity ◽  
Eugenia Dysenterica

This study was carried out to assess the genetic variability of ten "cagaita" tree (Eugenia dysenterica) populations in Southeastern Goiás. Fifty-four randomly amplified polymorphic DNA (RAPD) loci were used to characterize the population genetic variability, using the analysis of molecular variance (AMOVA). A phiST value of 0.2703 was obtained, showing that 27.03% and 72.97% of the genetic variability is present among and within populations, respectively. The Pearson correlation coefficient (r) among the genetic distances matrix (1 - Jaccard similarity index) and the geographic distances were estimated, and a strong positive correlation was detected. Results suggest that these populations are differentiating through a stochastic process, with restricted and geographic distribution dependent gene flow.

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