LEAF ESTERASE ISOZYMES IN AVENA AND THEIR RELATIONSHIP TO THE GENOMES

1972 ◽  
Vol 14 (3) ◽  
pp. 581-589 ◽  
Author(s):  
Iris L. Craig ◽  
Beatrice E. Murray ◽  
Tibor Rajhathy
Keyword(s):  
Natural Populations ◽  
Disc Electrophoresis ◽  
Cytological Evidence ◽  
Esterase Isozymes ◽  
Avena Species ◽  
High Affinity ◽  
A Genome ◽  
C Genome ◽  
Esterase Patterns

Leaf esterase patterns of natural populations of diploid, tetraploid and hexaploid Avena species were separated by disc electrophoresis. The zymotypes of the A genome diploids A. hirtula, A. strigosa and A. longiglumis differed from the C genome diploids A. pilosa and A. ventricosa. The tetraploids A. barbata, A. magna and A. murphyi had distinctive zymotypes. The A. barbata zymotype resembled the A genome diploids which supports the cytological evidence for homoeology between the genomes. Avena magna and A. murphyi were a combination of the A and C diploid patterns with A. murphyi resembling the C more than the A pattern. The zymotypes of the hexaploids A. sterilis and A. sativa revealed the expected A, C and AC genome ancestry. Band affinity ratings within and between genomic groups agreed with the cytological evidence and cross-compatible relationships, the exception being the C — AC species that have high affinity ratings but are apparently cross-incompatible.

EVOLUTION IN THE GENUS AVENA: INHERITANCE OF DIFFERENT FORMS OF RIBULOSE DIPHOSPHATE CARBOXYLASE

1975 ◽  
Vol 17 (3) ◽  
pp. 337-344 ◽  
Author(s):  
M. W. Steer
Keyword(s):  
Chloroplast Genome ◽  
Species Distribution ◽  
Diploid Species ◽  
Disc Electrophoresis ◽  
The Other ◽  
Avena Species ◽  
A Genome ◽  
C Genome ◽  
Evolutionary Paths ◽  
Ribulose Diphosphate Carboxylase

Disc electrophoresis of ribulose diphosphate carboxylases from Avena species in polyacrylamide gels of varying concentrations reveals the presence of two distinct forms of the enzyme. One migrates faster than the other and is found exclusively in species possessing the A genome. The other is confined to the C genome species (A. pilosa, A. ventricosa, A. clauda). The association of another characteristic of this enzyme (presence of stromacentres in the chloroplasts) with the A genome was reported previously. Observations on the recently described species A. prostrata, A. canariensis, A. damascena, and A. murphyi show that they all possess stromacentres, confirming reports that they all contain the A genome. Examination of amphiploid hybrids (from crosses between various diploid species and A. sativa) has shown that the mobility character is inherited maternally, and is located on the chloroplast genome. All these hybrids have the A genome and all have stromacentres. The results are discussed in the light of recent findings on the structure and synthesis of this enzyme. Consideration of the species distribution of the different forms of carboxylase places certain restrictions on the possible evolutionary paths from diploids to tetraploids and hexaploids.

ANALYSIS OF SPECIES RELATIONSHIPS IN AVENAE BY THIN-LAYER CHROMATOGRAPHY AND DISC ELECTROPHORESIS

1972 ◽  
Vol 14 (2) ◽  
pp. 305-316 ◽  
Author(s):  
H. C. Dass
Keyword(s):  
Thin Layer ◽  
Diploid Species ◽  
Disc Electrophoresis ◽  
Tetraploid Species ◽  
Species Relationships ◽  
D Genome ◽  
Genome Donor ◽  
A Genome ◽  
Layer Chromatography ◽  
Esterase Patterns

Thin-layer chromatographic studies on flavonoids, and disc electrophoretic studies on proteins and esterase isoenzymes were conducted with Avena to determine species relationships and genome homologies. Distinctness of Avena ventricosa and A. pilosa was observed in comparison to other diploid species. Closeness of the diploid species of the A. strigosa group (including hirtula and wiestii) was evident from the similarity of their protein and esterase spectra. The tetraploid species, A. barbata and A. abyssinica, were found to be very close to A. hirtula and A. strigosa, respectively, by TLC studies. Proteins and esterases also showed that the tetraploid species are very close to the A. strigosa group of diploid species. The contribution of a genome by the A. strigosa group to the tetraploids and hexaploids was confirmed. The hexaploids showed different protein and esterase patterns. The involvement of A. ventricosa as the C genome donor to the hexaploids was shown by the protein and esterase spectra. A few extra protein bands observed may have been from the D genome.

scholarly journals The Genetic Architecture of Ovariole Number in Drosophila melanogaster: Genes with Major, Quantitative, and Pleiotropic Effects

2017 ◽  
Vol 7 (7) ◽  
pp. 2391-2403 ◽  
Author(s):  
Amanda S Lobell ◽  
Rachel R Kaspari ◽  
Yazmin L Serrano Negron ◽  
Susan T Harbison
Keyword(s):  
Candidate Genes ◽  
Genome Wide Association Study ◽  
Natural Populations ◽  
Direct Role ◽  
Genome Wide ◽  
A Genome ◽  
Fitness Trait ◽  
Sleep Parameters ◽  
Activity Behavior ◽  
Ovariole Number

Abstract Ovariole number has a direct role in the number of eggs produced by an insect, suggesting that it is a key morphological fitness trait. Many studies have documented the variability of ovariole number and its relationship to other fitness and life-history traits in natural populations of Drosophila. However, the genes contributing to this variability are largely unknown. Here, we conducted a genome-wide association study of ovariole number in a natural population of flies. Using mutations and RNAi-mediated knockdown, we confirmed the effects of 24 candidate genes on ovariole number, including a novel gene, anneboleyn (formerly CG32000), that impacts both ovariole morphology and numbers of offspring produced. We also identified pleiotropic genes between ovariole number traits and sleep and activity behavior. While few polymorphisms overlapped between sleep parameters and ovariole number, 39 candidate genes were nevertheless in common. We verified the effects of seven genes on both ovariole number and sleep: bin3, blot, CG42389, kirre, slim, VAChT, and zfh1. Linkage disequilibrium among the polymorphisms in these common genes was low, suggesting that these polymorphisms may evolve independently.

scholarly journals Nucleotide sequences of highly repeated DNAs; compilation and comments

1982 ◽  
Vol 39 (1) ◽  
pp. 1-30 ◽  
Author(s):  
George L. Gabor Miklos ◽  
Amanda Clare Gill
Keyword(s):  
Satellite Dna ◽  
Germ Line ◽  
Sequence Data ◽  
Allelic Variation ◽  
Neutral Theory ◽  
Natural Populations ◽  
Evolutionary Significance ◽  
Nucleotide Sequence Data ◽  
A Genome ◽  
Repeated Dnas

SummaryThe nucleotide sequence data from highly repeated DNAs of inverte-brates and mammals are summarized and briefly discussed. Very similar conclusions can be drawn from the two data bases. Sequence complexities can vary from 2 bp to at least 359 bp in invertebrates and from 3 bp to at least 2350 bp in mammals. The larger sequences may or may not exhibit a substructure. Significant sequence variation occurs for any given repeated array within a species, but the sources of this heterogeneity have not been systematically partitioned. The types of alterations in a basic repeating unit can involve base changes as well as deletions or additions which can vary from 1 bp to at least 98 bp in length. These changes indicate that sequence per se is unlikely to be under significant biological constraints and may sensibly be examined by analogy to Kimura's neutral theory for allelic variation. It is not possible with the present evidence to discriminate between the roles of neutral and selective mechanisms in the evolution of highly repeated DNA.Tandemly repeated arrays are constantly subjected to cycles of amplification and deletion by mechanisms for which the available data stem largely from ribosomal genes. It is a matter of conjecture whether the solutions to the mechanistic puzzles involved in amplification or rapid redeployment of satellite sequences throughout a genome will necessarily give any insight into biological functions.The lack of significant somatic effects when the satellite DNA content of a genome is significantly perturbed indicates that the hunt for specific functions at the cellular level is unlikely to prove profitable.The presence or in some cases the amount of satellite DNA on a chromosome, however, can have significant effects in the germ line. There the data show that localized condensed chromatin, rich in satellite DNA, can have the effect of rendering adjacent euchromatic regions rec−, or of altering levels of recombination on different chromosomes. No data stemming from natural populations however are yet available to tell us if these effects are of adaptive or evolutionary significance.

Patterns of genome duplication within the Brassica napus genome

Genome ◽  
2003 ◽  
Vol 46 (2) ◽  
pp. 291-303 ◽  
Author(s):  
I A.P Parkin ◽  
A G Sharpe ◽  
D J Lydiate
Keyword(s):  
Brassica Napus ◽  
Genome Duplication ◽  
Chromosomal Rearrangements ◽  
Centric Fusion ◽  
Linkage Groups ◽  
Gross Chromosomal Rearrangements ◽  
A Genome ◽  
C Genome ◽  
Homologous Locus ◽  
Duplicate Loci

The progenitor diploid genomes (A and C) of the amphidiploid Brassica napus are extensively duplicated with 73% of genomic clones detecting two or more duplicate sequences within each of the diploid genomes. This comprehensive duplication of loci is to be expected in a species that has evolved through a polyploid ancestor. The majority of the duplicate loci within each of the diploid genomes were found in distinct linkage groups as collinear blocks of linked loci, some of which had undergone a variety of rearrangements subsequent to duplication, including inversions and translocations. A number of identical rearrangements were observed in the two diploid genomes, suggesting they had occurred before the divergence of the two species. A number of linkage groups displayed an organization consistent with centric fusion and (or) fission, suggesting this mechanism may have played a role in the evolution of Brassica genomes. For almost every genetically mapped locus detected in the A genome a homologous locus was found in the C genome; the collinear arrangement of these homologous markers allowed the primary regions of homoeology between the two genomes to be identified. At least 16 gross chromosomal rearrangements differentiated the two diploid genomes during their divergence from a common ancestor.Key words: genome evolution, Brassicaeae, polyploidy, homoeologous linkage groups.

EVOLUTION OF AVENA SATIVA: ORIGIN OF THE CYTOPLASMIC GENOME

1976 ◽  
Vol 18 (4) ◽  
pp. 769-771 ◽  
Author(s):  
Martin W. Steer ◽  
Hugh Thomas
Keyword(s):  
Avena Sativa ◽  
Conclusive Evidence ◽  
Cytoplasmic Genome ◽  
A Genome ◽  
Isoelectric Points ◽  
C Genome

Comparisons of the isoelectric points of the large subunits from the enzyme ribulose biphosphate carboxylase, extracted from species and hybrids of Avena, provide conclusive evidence for the origin of the cytoplasmic genome of the hexapioid A. sativa L. from the A. genome diploids rather than the C genome diploids.

The use of double fluorescence in situ hybridization to physically map the positions of 5S rDNA genes in relation to the chromosomal location of 18S–5.8S–26S rDNA and a C genome specific DNA sequence in the genus Avena

Genome ◽  
1996 ◽  
Vol 39 (3) ◽  
pp. 535-542 ◽  
Author(s):  
Concha Linares ◽  
Juan González ◽  
Esther Ferrer ◽  
Araceli Fominaya
Keyword(s):  
In Situ Hybridization ◽  
Dna Sequence ◽  
Diploid Species ◽  
5S Rdna ◽  
Rdna Genes ◽  
26S Rdna ◽  
A Genome ◽  
Rdna Loci ◽  
C Genome

A physical map of the locations of the 5S rDNA genes and their relative positions with respect to 18S–5.8S–26S rDNA genes and a C genome specific repetitive DNA sequence was produced for the chromosomes of diploid, tetraploid, and hexaploid oat species using in situ hybridization. The A genome diploid species showed two pairs of rDNA loci and two pairs of 5S loci located on both arms of one pair of satellited chromosomes. The C genome diploid species showed two major pairs and one minor pair of rDNA loci. One pair of subtelocentric chromosomes carried rDNA and 5S loci physically separated on the long arm. The tetraploid species (AACC genomes) arising from these diploid ancestors showed two pairs of rDNA loci and three pairs of 5S loci. Two pairs of rDNA loci and 2 pairs of 5S loci were arranged as in the A genome diploid species. The third pair of 5S loci was located on one pair of A–C translocated chromosomes using simultaneous in situ hybridization with 5S rDNA genes and a C genome specific repetitive DNA sequence. The hexaploid species (AACCDD genomes) showed three pairs of rDNA loci and six pairs of 5S loci. One pair of 5S loci was located on each of two pairs of C–A/D translocated chromosomes. Comparative studies of the physical arrangement of rDNA and 5S loci in polyploid oats and the putative A and C genome progenitor species suggests that A genome diploid species could be the donor of both A and D genomes of polyploid oats. Key words : oats, 5S rDNA genes, 18S–5.8S–26S rDNA genes, C genome specific repetitive DNA sequence, in situ hybridization, genome evolution.

Genome elimination in diploid and triploid Rana esculenta males: cytological evidence from DNA flow cytometry

Genome ◽  
1990 ◽  
Vol 33 (5) ◽  
pp. 619-627 ◽  
Author(s):  
A. E. Vinogradov ◽  
L. J. Borkin ◽  
R. Günther ◽  
J. M. Rosanov
Keyword(s):  
Flow Cytometry ◽  
Genetic Material ◽  
Rana Esculenta ◽  
Mendelian Inheritance ◽  
Study Data ◽  
Dna Flow Cytometry ◽  
Cytological Evidence ◽  
Water Frog ◽  
A Genome ◽  
Rana Lessonae

Cytological aspects of hemiclonal (meroclonal) inheritance in diploid and triploid males of the hybridogenetic frog Rana esculenta (Rana ridibunda × Rana lessonae) have been studied by DNA flow cytometry. The fact that the R. ridibunda genome contains 16% more DNA than the R. lessonae genome provides the ability to discern cells containing genomes of any species from the water-frog complex under study. Data are presented showing that elimination of the R. ridibunda genome occurs in hybridogenetic males from certain populations. In triploid males, the cytogenetic mechanism of hemiclonal inheritance is simpler than in diploids: after the elimination of a genome (always the genome in the minority in the triploid set; "homogenizing elimination"), no compensatory duplication of the remaining genetic material is necessary, as it is in diploids. The process of elimination can be visualized in triploid males by using DNA flow cytometry to identify cells in the special phase of the spermatogonial cell cycle that we termed the E phase.Key words: Rana esculenta, genome elimination, non-Mendelian inheritance, spermatogenesis, DNA flow cytometry.

scholarly journals Predicting the Landscape of Recombination Using Deep Learning

2020 ◽  
Vol 37 (6) ◽  
pp. 1790-1808 ◽  
Author(s):  
Jeffrey R Adrion ◽  
Jared G Galloway ◽  
Andrew D Kern
Keyword(s):  
Deep Learning ◽  
Evolutionary History ◽  
Model Misspecification ◽  
Natural Populations ◽  
High Accuracy ◽  
Demographic Model ◽  
Recombination Rates ◽  
Genome Wide ◽  
A Genome ◽  
The Face

Abstract Accurately inferring the genome-wide landscape of recombination rates in natural populations is a central aim in genomics, as patterns of linkage influence everything from genetic mapping to understanding evolutionary history. Here, we describe recombination landscape estimation using recurrent neural networks (ReLERNN), a deep learning method for estimating a genome-wide recombination map that is accurate even with small numbers of pooled or individually sequenced genomes. Rather than use summaries of linkage disequilibrium as its input, ReLERNN takes columns from a genotype alignment, which are then modeled as a sequence across the genome using a recurrent neural network. We demonstrate that ReLERNN improves accuracy and reduces bias relative to existing methods and maintains high accuracy in the face of demographic model misspecification, missing genotype calls, and genome inaccessibility. We apply ReLERNN to natural populations of African Drosophila melanogaster and show that genome-wide recombination landscapes, although largely correlated among populations, exhibit important population-specific differences. Lastly, we connect the inferred patterns of recombination with the frequencies of major inversions segregating in natural Drosophila populations.

Comparative cytogenetic analysis of Avena macrostachya and diploid C-genome Avena species

Genome ◽  
2010 ◽  
Vol 53 (2) ◽  
pp. 125-137 ◽  
Author(s):  
Ekaterina D. Badaeva ◽  
Olga Yu. Shelukhina ◽  
Axel Diederichsen ◽  
Igor G. Loskutov ◽  
Vitaly A. Pukhalskiy
Keyword(s):  
5S Rdna ◽  
Nucleolar Organizer ◽  
Nucleolar Organizer Regions ◽  
Rrna Gene ◽  
Avena Species ◽  
Rdna Sites ◽  
C Genome ◽  
Genome Group ◽  
26S Rrna

The chromosome set of Avena macrostachya Balansa ex Coss. et Durieu was analyzed using C-banding and fluorescence in situ hybridization with 5S and 18S-5.8S-26S rRNA gene probes, and the results were compared with the C-genome diploid Avena L. species. The location of major nucleolar organizer regions and 5S rDNA sites on different chromosomes confirmed the affiliation of A. macrostachya with the C-genome group. However, the symmetric karyotype, the absence of “diffuse heterochromatin”, and the location of large C-band complexes in proximal chromosome regions pointed to an isolated position of A. macrostachya from other Avena species. Based on the distribution of rDNA loci on the C-genome chromosomes of diploid and polyploid Avena species, we propose a model of the chromosome alterations that occurred during the evolution of oat species.

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