A comparative karyological study of the blue-breasted quail (Coturnix chinensis, Phasianidae) and California quail (Callipepla californica, Odontophoridae).
ABSTRACT We conducted comparative chromosome painting and chromosome mapping with chicken DNA probes against the blue-breasted quail (Coturnix chinensis, CCH) and California quail (Callipepla californica, CCA), which are classified into the Old World quail and the New World quail, respectively. Each chicken probe of chromosomes 1-9 and Z painted a pair of chromosomes in the blue-breasted quail. In California quail, chicken chromosome 2 probe painted chromosomes 3 and 6, and chicken chromosome 4 probe painted chromosomes 4 and a pair of microchromosomes. Comparison of the cytogenetic maps of the two quail species with those of chicken and Japanese quail revealed that there are several intrachromosomal rearrangements, pericentric and/or paracentric inversions, in chromosomes 1, 2 and 4 between chicken and the Old World quail. In addition, a pericentric inversion was found in chromosome 8 between chicken and the three quail species. Ordering of the Z-linked DNA clones revealed the presence of multiple rearrangements in the Z chromosomes of the three quail species. Comparing these results with the molecular phylogeny of Galliformes species, it was also cytogenetically supported that the New World quail is classified into a different clade from the lineage containing chicken and the Old World quail.
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ABSTRACT: Many families of centromeric repetitive DNA sequences isolated from Struthioniformes, Galliformes, Falconiformes, and Passeriformes are localized primarily to microchromosomes. However, it is unclear whether chromosome size-correlated homogenization is a common characteristic of centromeric repetitive sequences in Aves. New World and Old World quails have the typical avian karyotype comprising chromosomes of two distinct sizes, and C-positive heterochromatin is distributed in centromeric regions of most autosomes and the whole W chromosome. We isolated six types of centromeric repetitive sequences from three New World quail species (Colinus virginianus, CVI; Callipepla californica, CCA; and Callipepla squamata, CSQ; Odontophoridae) and one Old World quail species (Alectoris chukar, ACH; Phasianidae), and characterized the sequences by nucleotide sequencing, chromosome in situ hybridization, and filter hybridization. The 385-bp CVI-MspI, 591-bp CCA-BamHI, 582-bp CSQ-BamHI, and 366-bp ACH-Sau3AI fragments exhibited tandem arrays of the monomer unit, and the 224-bp CVI-HaeIII and 135-bp CCA-HaeIII fragments were composed of minisatellite-like and microsatellite-like repeats, respectively. ACH-Sau3AI was a homolog of the chicken nuclear membrane repeat sequence, whose homologs are common in Phasianidae. CVI-MspI, CCA-BamHI, and CSQ-BamHI showed high homology and were specific to the Odontophoridae. CVI-MspI was localized to microchromosomes, whereas CVI-HaeIII, CCA-BamHI, and CSQ-BamHI were mapped to almost all chromosomes. CCA-HaeIII was localized to five pairs of macrochromosomes and most microchromosomes. ACH-Sau3AI was distributed in three pairs of macrochromosomes and all microchromosomes. Centromeric repetitive sequences may be homogenized in chromosome size-correlated and -uncorrelated manners in New World quails, although there may be a mechanism that causes homogenization of centromeric repetitive sequences primarily between microchromosomes, which is commonly observed in phasianid birds.Chromosome Research 02/2014; · 2.69 Impact Factor
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ABSTRACT: The stone curlew, also known as thick-knee (Burhinus oedicnemus, BOE), represents a phylogenetically young species of the shorebirds (Charadriiformes) that exhibits one of the most atypical genome organizations known within the class of Aves, due to an extremely low diploid number (2n = 42) and only 6 pairs of microchromosomes in its complement. This distinct deviation from the 'typical' avian karyotype is attributed to repeated fusions of ancestral microchromosomes. In order to compare different species with this atypical avian karyotype and to investigate the chromosome rearrangement patterns, chromosome-specific painting probes representing the whole genome of the stone curlew were used to delineate chromosome homology between BOE and 5 species belonging to 5 different avian orders: herring gull (Charadriiformes), cockatiel (Psittaciformes), rock pigeon (Columbiformes), great gray owl (Strigiformes) and Eurasian coot (Gruiformes). Paints derived from the 20 BOE autosomes delimited 28 to 33 evolutionarily conserved segments in the karyotypes of the 5 species, similar to the number recognized by BOE paints in such a basal lineage as the chicken (28 conserved segments). This suggests a high degree of conservation in genome organization in birds. BOE paints also revealed some species-specific rearrangements. In particular, chromosomes BOE1-4 and 14, as well as to a large extent BOE5 and 6, showed conserved synteny with macrochromosomes, whereas homologous regions for BOE7-13 are found to be largely distributed on microchromosomes in the species investigated. Interestingly, the 6 pairs of BOE microchromosomes 15-20 appear to have undergone very few rearrangements in the 5 lineages investigated. Although the arrangements of BOE homologous segments on some chromosomes can be explained by complex fusions and inversions, the occurrence of homologous regions at multiple sites may point to fission of ancestral chromosomes in the karyotypes of the species investigated. However, the present results demonstrate that the ancestral microchromosomes most likely experienced fusion in the stone curlew lineage forming the medium-sized BOE chromosomes, while they have been conserved as microchromosomes in the other neoavian lineages.Cytogenetic and Genome Research 01/2009; 126(3):281-304. · 1.84 Impact Factor
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ABSTRACT: It is generally believed that the organization of avian genomes remains highly conserved in evolution as chromosome number is constant and comparative chromosome painting demonstrated there to be very few interchromosomal rearrangements. The recent sequencing of the zebra finch (Taeniopygia guttata) genome allowed an assessment of the number of intrachromosomal rearrangements between it and the chicken (Gallus gallus) genome, revealing a surprisingly high number of intrachromosomal rearrangements. With the publication of the turkey (Meleagris gallopavo) genome it has become possible to describe intrachromosomal rearrangements between these three important avian species, gain insight into the direction of evolutionary change and assess whether breakpoint regions are reused in birds. To this end, we aligned entire chromosomes between chicken, turkey and zebra finch, identifying syntenic blocks of at least 250 kb. Potential optimal pathways of rearrangements between each of the three genomes were determined, as was a potential Galliform ancestral organization. From this, our data suggest that around one-third of chromosomal breakpoint regions may recur during avian evolution, with 10% of breakpoints apparently recurring in different lineages. This agrees with our previous hypothesis that mechanisms of genome evolution are driven by hotspots of non-allelic homologous recombination.Heredity 11/2011; 108(1):37-41. · 3.80 Impact Factor