scholarly journals High BrdU Sensitivity of Passeriformes Chromosomes: Conservation of BrdU-Sensitive Fragile Sites on Their Z Chromosomes during Evolution

2019 ◽  
Vol 157 (3) ◽  
pp. 158-165 ◽  
Author(s):  
Michèle Gerbault-Seureau ◽  
Jérôme Fuchs ◽  
Bernard Dutrillaux
Keyword(s):  
Culture Medium ◽  
Chromosome Structure ◽  
Fragile Site ◽  
Bird Species ◽  
Parus Major ◽  
Structural Rearrangement ◽  
Fragile Sites ◽  
Brdu Incorporation ◽  
Z Chromosome ◽  
Erithacus Rubecula

Amongst 15 bird species, representative of 7 orders, recurrent breakages evocating the presence of fragile sites were detected in the chromosomes of the 5 species belonging to Passeriformes. These breaks appeared when 5-bromodeoxyuridine (BrdU) was added to the cell culture medium at a dose inefficient for inducing chromosome structure alterations in other birds and mammals. They involved, similarly in male and female, 3 loci on the Z chromosome of 3 Turdus species (Turdidae). Labeling by BrdU antibody confirmed the correlation between BrdU incorporation into DNA and breakage, especially around and in the sites of breakage. Thus, 3 BrdU-sensitive fragile sites were present in the Z chromosomes of these birds. Three fragile sites were also detected at different locations in the Z chromosomes of the European robin (Erithacus rubecula, Muscicapidae), suggesting that a structural rearrangement occurred during the evolution of Turdidae and Muscicapidae. Chromosome banding confirmed this interpretation. Finally, in the more distantly related species Parus major (Paridae), the almost acrocentric Z chromosome displayed a single BrdU-sensitive fragile site in its short arm, and the W appeared to be pulverized by BrdU incorporation. Although it cannot be excluded that the BrdU-sensitive fragile sites may be involved in rearrangements, their conservation in many species, and possibly all Passeriformes, provides evidence that they do not constitute a pejorative character during evolution.

Effects of ectoparasites on breeding success of great tits (Parus major) and pied flycatchers (Ficedula hypoleuca) in an air pollution gradient

1994 ◽  
Vol 72 (4) ◽  
pp. 624-635 ◽  
Author(s):  
Tapio Eeva ◽  
Esa Lehikoinen ◽  
Jorma Nurmi
Keyword(s):  
Heavy Metals ◽  
Air Pollution ◽  
Breeding Success ◽  
Detrimental Effect ◽  
Bird Species ◽  
Parus Major ◽  
Ficedula Hypoleuca ◽  
Nest Size ◽  
Minor Importance ◽  
Ceratophyllus Gallinae

Numbers of ectoparasitic blow fly (Protocalliphora azurea) larvae (Diptera: Calliphoridae), adult and larval hen fleas, Ceratophyllus gallinae (Siphonaptera: Ceratophyllidae), and other nest-dwelling insects were counted from the nests of the great tit, Parus major, and the pied flycatcher, Ficedula hypoleuca, in southwestern Finland around a factory complex emitting large quantities of sulphuric oxides and heavy metals. Protocalliphora azurea larvae were more frequently found in the nests of P. major than in those of F. hypoleuca. The prevalence of P. azurea larvae tended to be lower in polluted areas. The number of P. azurea larvae correlated positively with nest size and brood size of P. major. This may be caused by difficulties in sanitation of large and crowded nests. The numbers of fleas and their larvae were negatively affected by moisture in the nests. Nests of F. hypoleuca contained more adult fleas in polluted areas. This may indicate reduced resistance of birds exposed to heavy metals, but other possibilities are also discussed. We found a detrimental effect of P. azurea larvae on the growth of P. major nestlings, and an effect of fleas on mortality of F. hypoleuca nestlings, but these effects were not enhanced by air pollution. We conclude that the ectoparasites studied, at densities observed in our study area, are of minor importance in determining the breeding success of these two bird species.

Fragile Sites on Chromosomes

PEDIATRICS ◽  
1982 ◽  
Vol 69 (1) ◽  
pp. 121-123
Author(s):  
Frederick Hecht ◽  
Thomas W. Glover ◽  
Barbara Kaiser-Hecht
Keyword(s):  
Mental Retardation ◽  
X Chromosome ◽  
Fanconi Anemia ◽  
Ataxia Telangiectasia ◽  
Autosomal Recessive ◽  
Fragile Site ◽  
Chromosome Instability ◽  
Chromosome Complement ◽  
Fragile Sites ◽  
Chromosome Fragility

A fragile site on the X chromosome is associated with a common form of mental retardation in males and a proportion of females.1-3 This association was not fully appreciated when the fragile site on the X was first described in 1969,4 but it is crystal-clear today. Chromosome fragility can be random, as in Fanconi anemia, Bloom syndrome, and ataxia-telangiectasia, the chromosome instability syndromes.5 Breaks and rearrangements of chromosomes are seen in these disorders, all of which are autosomal recessive conditions predisposing to cancer. Fragile sites are special spots in the genome where gaps and breaks occur nonrandomly. The balance of the chromosome complement is normal.

Generation of a new adenovirus type 12-inducible fragile site by insertion of an artificial U2 locus in the human genome

1993 ◽  
Vol 13 (10) ◽  
pp. 6064-6070
Author(s):  
Y P Li ◽  
R Tomanin ◽  
J R Smiley ◽  
S Bacchetti
Keyword(s):  
Human Genome ◽  
Gene Cluster ◽  
Fragile Site ◽  
Adenovirus Type ◽  
Fragile Sites ◽  
Human Cells ◽  
Major Site ◽  
Chromosome 13 ◽  
Direct Assessment

Infection with adenovirus type 12 (Ad12) induces four fragile sites in the human genome (H.F. Stich, G.L. van Hoosier, and J.J. Trentin, Exp. Cell Res. 34:400-403, 1964; H. zur Hausen, J. Virol. 1:1174-1185, 1967). The major site, at 17q21-22, contains the U2 gene cluster, which is specifically disrupted by infection in at least a percentage of the cells (D.M. Durnam, J.C. Menninger, S.H. Chandler, P.P. Smith, and J.K. McDougall, Mol. Cell. Biol. 8:1863-1867, 1988). For direct assessment of whether the U2 locus is the target of the Ad12 effect, an artificial locus, constructed in vitro and consisting of tandem arrays of the U2 6-kbp monomer, was transfected into human cells. We report that integration of this artificial locus on the p arm of chromosome 13 creates a new Ad12-inducible fragile site.

scholarly journals Breeding bird communities in an area of the Northern Apennines (Piedmont, NW Italy)

2019 ◽  
Vol 88 (2) ◽  
pp. 23-32
Author(s):  
Franco Carpegna ◽  
Giovanni Soldato ◽  
Roberto Toffoli
Keyword(s):  
Regional Scale ◽  
Parus Major ◽  
Bird Community ◽  
Erithacus Rubecula ◽  
Sylvia Atricapilla ◽  
Mountain Areas ◽  
Fringilla Coelebs ◽  
Turdus Merula ◽  
Nw Italy ◽  
Agricultural Areas

During the Spring of 2011, we studied the bird community in an area of Val Borbera, in the province of Alessandria (NW Italy). In the study area, situated at an altitude between 655 and 1700 m a.s.l., we conducted 110 points count ten minutes each in four microhabitats (agricultural areas, shrubs, forests, and prairies). In total, we surveyed 72 species, of which 51 were passerine and 21 non passerine. The most abundant species were Sylvia atricapilla, Phylloscopus collybita, Apus apus, and Turdus merula. In the agricultural areas, we detected a total of 50 species (Sylvia atricapilla, Parus major, Turdus merula were the most abundant). In the shrubs, we detected 30 species (Sylvia atricapilla, Parus major, Fringilla coelebs, Phylloscopus collybita, Turdus merula, Erithacus rubecula were the most abundant). In the forest areas, we found 45 species (Sylvia atricapilla, Parus major, Fringilla coelebs, Phylloscopus collybita, Turdus merula, Erithacus rubecula were the most abundant), and in the prairies, we detected 48 species (Alauda arvensis, Anthus campestris, Sylvia atricapilla, Turdus merula, Anthus trivialis, Sylvia communis were the most abundant). Compared to the other macro habitats, the agricultural areas have a significantly high abundance and richness in species, which highlights the importance of the agricultural mosaics in the Piedmont and mountain areas. The data which has been collected so far confirms the important role of this area, given the presence of some species which are rare at a regional scale.

scholarly journals Increased Common Fragile Site Expression, Cell Proliferation Defects, and Apoptosis following Conditional Inactivation of Mouse Hus1 in Primary Cultured Cells

2007 ◽  
Vol 18 (3) ◽  
pp. 1044-1055 ◽  
Author(s):  
Min Zhu ◽  
Robert S. Weiss
Keyword(s):  
Cell Cycle ◽  
Cultured Cells ◽  
Chromosomal Abnormalities ◽  
Fragile Site ◽  
Loxp Site ◽  
Fragile Sites ◽  
Cell Cycle Checkpoint ◽  
Dna Breaks ◽  
Common Fragile Sites ◽  
Histone H2ax

Targeted disruption of the mouse Hus1 cell cycle checkpoint gene results in embryonic lethality and proliferative arrest in cultured cells. To investigate the essential functions of Hus1, we developed a system for the regulated inactivation of mouse Hus1 in primary fibroblasts. Inactivation of a loxP site-flanked conditional Hus1 allele by using a cre-expressing adenovirus resulted in reduced cell doubling, cell cycle alterations, and increased apoptosis. These phenotypes were associated with a significantly increased frequency of gross chromosomal abnormalities and an S-phase–specific accumulation of phosphorylated histone H2AX, an indicator of double-stranded DNA breaks. To determine whether these chromosomal abnormalities occurred randomly or at specific genomic regions, we assessed the stability of common fragile sites, chromosomal loci that are prone to breakage in cells undergoing replication stress. Hus1 was found to be essential for fragile site stability, because spontaneous chromosomal abnormalities occurred preferentially at common fragile sites upon conditional Hus1 inactivation. Although p53 levels increased after Hus1 loss, deletion of p53 failed to rescue the cell-doubling defect or increased apoptosis in conditional Hus1 knockout cells. In summary, we propose that Hus1 loss leads to chromosomal instability during DNA replication, triggering increased apoptosis and impaired proliferation through p53-independent mechanisms.

scholarly journals DNA synthesis by Pol η promotes fragile site stability by preventing under-replicated DNA in mitosis

2013 ◽  
Vol 201 (3) ◽  
pp. 395-408 ◽  
Author(s):  
Valérie Bergoglio ◽  
Anne-Sophie Boyer ◽  
Erin Walsh ◽  
Valeria Naim ◽  
Gaëlle Legube ◽  
...  
Keyword(s):  
Dna Synthesis ◽  
Dna Sequences ◽  
Molecular Mechanisms ◽  
Fragile Site ◽  
Fragile Sites ◽  
Nuclear Bodies ◽  
Replication Checkpoint ◽  
Genome Damage ◽  
Fork Stalling ◽  
The Stability

Human DNA polymerase η (Pol η) is best known for its role in responding to UV irradiation–induced genome damage. We have recently observed that Pol η is also required for the stability of common fragile sites (CFSs), whose rearrangements are considered a driving force of oncogenesis. Here, we explored the molecular mechanisms underlying this newly identified role. We demonstrated that Pol η accumulated at CFSs upon partial replication stress and could efficiently replicate non-B DNA sequences within CFSs. Pol η deficiency led to persistence of checkpoint-blind under-replicated CFS regions in mitosis, detectable as FANCD2-associated chromosomal sites that were transmitted to daughter cells in 53BP1-shielded nuclear bodies. Expression of a catalytically inactive mutant of Pol η increased replication fork stalling and activated the replication checkpoint. These data are consistent with the requirement of Pol η–dependent DNA synthesis during S phase at replication forks stalled in CFS regions to suppress CFS instability by preventing checkpoint-blind under-replicated DNA in mitosis.

Effects of folate in culture medium on common fragile sites in lymphocyte chromosomes from normal and leukemic children

1988 ◽  
Vol 81 (1) ◽  
pp. 9-12 ◽  
Author(s):  
Richard J. Green ◽  
Donald L. Phillips ◽  
Andrew T. L. Chen ◽  
John A. Reidy ◽  
Abdel H. Ragab
Keyword(s):  
Culture Medium ◽  
Fragile Sites ◽  
Common Fragile Sites

scholarly journals The transcriptionally competent U2 gene is necessary and sufficient for adenovirus type 12 induction of the fragile site at 17q21-22.

1995 ◽  
Vol 15 (11) ◽  
pp. 6256-6261 ◽  
Author(s):  
S Gargano ◽  
P Wang ◽  
E Rusanganwa ◽  
S Bacchetti
Keyword(s):  
Human Genome ◽  
Tandem Repeats ◽  
Fragile Site ◽  
Adenovirus Type ◽  
Fragile Sites ◽  
Human Cells ◽  
Necessary And Sufficient

Adenovirus type 12 induces four fragile sites upon infection of human cells. The U2 locus, consisting of up to 20 tandem repeats of a 5.8-kbp monomer, maps at the most sensitive of these sites at 17q21-22. We have previously shown that an artificial U2 locus integrated into the human genome generates a new virus-induced fragile site. To determine which elements within the U2 monomer are responsible for fragility, we constructed loci consisting of tandem repeats of subfragments of the U2 monomer. With this approach, we demonstrate that a transcriptionally competent U2 gene is necessary and sufficient for virus-induced fragility and that no other element within the 5.8-kbp monomer contributes to this effect.

scholarly journals Formation of nesting bird communities in parks on the gradient of anthropic load in Kiev metropolis

2020 ◽  
Vol 2020 (23) ◽  
pp. 41-59
Author(s):  
T. V. Shupova ◽  
◽  
S. N. Koniakin ◽  
Keyword(s):  
Species Composition ◽  
Passer Domesticus ◽  
Parus Major ◽  
Columba Livia ◽  
Sturnus Vulgaris ◽  
Bird Communities ◽  
Ficedula Albicollis ◽  
Erithacus Rubecula ◽  
Passer Montanus ◽  
Nesting Density

In settlements, safe places for birds nesting and feeding need to be created. The purpose of the work is to assess the state and identify vectors of the formation of nesting bird communities in parks under the pressure of anthropic load in the metropolis. In parks of Kyiv 62 species of birds nest. Such faunogenetic complexes like European nemoral (25.0–53.3%), Desert-mountain (12.0–27.8%) and Forest-steppe (6.9–25.0%) prevail. The number of community species in each of parks is 49–12, the average nesting density is 0.08±0.02–0.9±0.19 pairs / ha, and the dispersion is 0.12–1.62. With the combination of anthropic load on biotopes of more than 140 points with a small area of parks (2.0–16.5 ha), the species composition of communities decreases, and the average nesting density and density dispersion increase. Dominated by density: Parus major, Columba livia, Sturnus vulgaris, Turdus merula, Passer domesticus, Passer montanus, Fringilla coelebs, Columba palumbus, Apus apus, Ficedula albicollis, Erithacus rubecula, Turdus pilaris. All birds in communities are obligate synanthropes (12.9%; n=62) or hemisinanthropes. Obligate synanthropes are distributed in communities of 0-7 species. According to the gradient of increasing anthropic load on parks, logarithmic trends show a slight increase in the percentage share of obligate synanthropes in the species composition and in the number of breeding pairs. 47–70% nest on trees, 0–14.3% in shrubs, 0–13.0% on ground and in buildings. In parks, birds (16–38% of the species composition), in addition to using species-specific stations, nest in the cavities of buildings. Such species like Motacilla alba L., Sturnus vulgaris, Ficedula albicollis, Muscicapa striata Pallas, Erithacus rubecula, Parus major, Passer domesticus, Passer montanus nest in this way. Due to this nesting strategy, the need of the birds in hollows and the dependence on the woodpeckers in the community decreases. High parameters of the Shannon index (1.51–3.14) and Pielou index (0.61–0.95) were revealed, with low data of the Berger-Parker index (0.15–0.61). With an anthropic load of more than 160 points, there is a sharp decrease in species diversity, evenness of species, and increased dominance pressure. Cluster analysis showed the division of bird communities into similarity groups according to the area of the parks, the proximity of parks to the outskirts of the city and large forest tracts of the area and specifics of the anthropic load.

scholarly journals Great Tits Learn Odors and Colors Equally Well, and Show No Predisposition for Herbivore-Induced Plant Volatiles

2022 ◽  
Vol 9 ◽  
Author(s):  
Diana Rubene ◽  
Utku Urhan ◽  
Velemir Ninkovic ◽  
Anders Brodin
Keyword(s):  
Plant Volatiles ◽  
Visual Cues ◽  
Bird Species ◽  
Parus Major ◽  
Insectivorous Birds ◽  
Learning Abilities ◽  
Induced Plant Volatiles ◽  
Learning Speed ◽  
Herbivore Induced Plant Volatiles ◽  
Good Learning

Ability to efficiently localize productive foraging habitat is crucial for nesting success of insectivorous birds. Some bird species can use olfaction to identify caterpillar-infested trees by detection of herbivore induced plant volatiles (HIPVs), but these cues probably need to be learned. So far, we know very little about the process of olfactory learning in birds, whether insectivorous species have a predisposition for detecting and learning HIPVs, due to the high ecological significance of these odors, and how olfaction is integrated with vision in making foraging decisions. In a standardized setup, we tested whether 35 wild-caught great tits (Parus major) show any preference for widely abundant HIPVs compared to neutral (non-induced) plant odors, how fast they learn to associate olfactory, visual and multimodal foraging cues with food, and whether the olfactory preferences and learning speed were influenced by bird sex or habitat (urban or rural). We also tested how fast birds switch to a new cue of the same modality. Great tits showed no initial preference for HIPVs compared to neutral odors, and they learned all olfactory cues at a similar pace, except for methyl salicylate (MeSA), which they learned more slowly. We also found no differences in learning speeds between visual, olfactory and multimodal foraging cues, but birds learned the second cue they were offered faster than the first one. Bird sex or habitat had no effect on learning speed or olfactory preference, but urban birds tended to learn visual cues more slowly. We conclude that insectivorous birds utilize olfactory and visual cues with similar efficiency in foraging, and that they probably don‘t have any special predisposition toward the tested HIPVs. These results confirm that great tits are flexible foragers with good learning abilities.

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