Identification of chromosome instability in Japanese quail (Coturnix japonica)

1. A study of the incidence of chromosome instability in the Japanese quail as assessed by sister chromatid exchange (SCE) and fragile site identification in chromosomes was conducted in two parent breeds and their F1 and F2 generations. 2. The mean incidence of SCEs was 6.02 ± 0.45 and the frequency of fragile sites was 1.17 ± 0.79. 3. There were moderately negative correlations of 0.51-0.64 between chromosome instability and fertility in the F1 and 0.10-0.23 in the F2. The hatch of fertilised eggs was negatively correlated with the number of SCE in male (0.31) and female (0.33) F1 and was lower in P (0.18 and 0.19, respectively), whereas the correlations were similar for the number of fragile sites in both generations (0.51-0.62).

Aberrant hetero-disulfide bond formation by the hypertriglyceridemia-associated p.Gly185Cys APOA5 variant (rs2075291)

OBJECTIVE

Apolipoprotein A-V (apoA-V) is a low-abundance plasma protein that modulates triacylglycerol homeostasis. Gene transfer studies were undertaken in apoa5 (-/-) mice to define the mechanism underlying the correlation between the single-nucleotide polymorphism c.553G>T in APOA5 and hypertriglyceridemia.

APPROACH AND RESULTS

Adeno-associated virus (AAV) 2/8-mediated gene transfer of wild-type apoA-V induced a dramatic lowering of plasma triacylglycerol in apoa5 (-/-) mice, whereas AAV2/8-Gly162Cys apoA-V (corresponding to the c.553G>T single-nucleotide polymorphism: rs2075291; p.Gly185Cys when numbering includes signal sequence) had a modest effect. Characterization studies revealed that plasma levels of wild-type and G162C apoA-V in transduced mice were similar and within the physiological range. Fractionation of plasma from mice transduced with AAV2/8-G162C apoA-V indicated that, unlike wild-type apoA-V, >50% of G162C apoA-V was recovered in the lipoprotein-free fraction. Nonreducing SDS-PAGE immunoblot analysis provided evidence that G162C apoA-V present in the lipoprotein-free fraction, but not that portion associated with lipoproteins, displayed altered electrophoretic mobility consistent with disulfide-linked heterodimer formation. Immunoprecipitation followed by liquid chromatography/mass spectrometry of human plasma from subjects homozygous for wild-type APOA5 and c.553G>T APOA5 revealed that G162C apoA-V forms adducts with extraneous plasma proteins including fibronectin, kininogen-1, and others.

CONCLUSIONS

Substitution of Cys for Gly at position 162 of mature apoA-V introduces a free cysteine that forms disulfide bonds with plasma proteins such that its lipoprotein-binding and triacylglycerol-modulation functions are compromised.

Growth performance, meat quality traits, and genetic mapping of quantitative trait loci in 3 generations of Japanese quail populations (Coturnix japonica)

The current research was conducted to compare growth, carcass traits, pH, intramuscular collagen (IMC) properties, and genetic bases of IMC and carcasses (breast-muscle weight) of different lines and generations of adult males and females of Japanese quail (Coturnix japonica). Forty-four quails (generation F0), 22 Pharaoh (F-33) meat-type males and 22 Standard (S-22) laying-type females, were crossed to produce the F1 hybrids generation. The F2 generation was created by mating one F1 male with one F1 female, full siblings. The birds, randomly chosen from F0 (22 males and 22 females), F1 (22 males and 22 females), and F2 (84 males and 152 females) were raised to 20 wk of age in collective cages. Quails were fed ad libitum commercial diets. At slaughter, all birds were individually weighed (after a fasting period of 12 h) and dressing yield (without giblets) was calculated. The carcasses were then dissected. Genomic DNA was extracted from all of the blood, and 30 microsatellite markers located on 2 quail chromosomes were genotyped. The F -: 33 quails had higher in vivo and postmortem performances and a higher abdominal fat percentage than those of the egg line. Meat from S -: 22 quails had a slower collagen maturation (hydroxylysylpyridinoline crosslink/collagen) and a higher ultimate pH. The F1 and F2 generations showed an evident sexual dimorphism, and an additional effect could be due to hybrid heterosis evident in F2. Meat from quails of F1 and F2 generations had a lower IMC amount with a higher degree of collagen maturation compared with parental lines. Two statistically significant QTL have been detected on quail chromosome 2 (CJA02): a QTL with an additive effect (0.50) for IMC in the marker bracket GUJ0037 and GUJ0093; a second QTL with additive (1.32) and dominant (1.91) effects for breast-muscle weight in the marker bracket GUJ0084 and GUJ0073. To our knowledge, this is the first report of a QTL associated with breast-muscle weight and IMC in quail and poultry species, respectively.

Echoes from the past: a healthy Baltic Sea requires more effort

Integrated sediment multiproxy studies and modeling were used to reconstruct past changes in the Baltic Sea ecosystem. Results of natural changes over the past 6000 years in the Baltic Sea ecosystem suggest that forecasted climate warming might enhance environmental problems of the Baltic Sea. Integrated modeling and sediment proxy studies reveal increased sea surface temperatures and expanded seafloor anoxia (in deep basins) during earlier natural warm climate phases, such as the Medieval Climate Anomaly. Under future IPCC scenarios of global warming, there is likely no improvement of bottom water conditions in the Baltic Sea. Thus, the measures already designed to produce a healthier Baltic Sea are insufficient in the long term. The interactions between climate change and anthropogenic impacts on the Baltic Sea should be considered in management, implementation of policy strategies in the Baltic Sea environmental issues, and adaptation to future climate change.

A model for treating avian aspergillosis: serum and lung tissue kinetics for Japanese quail (Coturnix japonica) following single and multiple aerosol exposures of a nanoparticulate itraconazole suspension

Aspergillosis is frequently reported in parrots, falcons and other birds held in captivity. Inhalation is the main route of infection for Aspergillus fumigatus, resulting in both acute and chronic disease conditions. Itraconazole (ITRA) is an antifungal commonly used in birds, but administration requires repeated oral dosing and the safety margin is narrow. We describe lung tissue and serum pharmacokinetics of a nanoparticulate ITRA suspension administered to Japanese quail by aerosol exposure. Aerosolized ITRA (1 and 10% suspension) administered over 30 min did not induce adverse clinical reactions in quail upon single or 5-day repeated doses. High lung concentrations, well above the inhibitory levels for A. fumigatus, of 4.14 ± 0.19 μg/g and 27.5 ± 4.58 μg/g (mean ± SEM, n = 3), were achieved following single-dose inhalation of 1% and 10% suspension, respectively. Upon multiple dose administration of 10% suspension, mean lung concentrations reached 104.9 ± 10.1 μg/g. Drug clearance from the lungs was slow with terminal half-lives of 19.7 h and 35.8 h following inhalation of 1% and 10% suspension, respectively. Data suggest that lung clearance is solubility driven. Lung concentrations of hydroxy-itraconazole reached 1-2% of the ITRA lung tissue concentration indicating metabolism in lung tissue. Steady, but low, serum concentrations of ITRA could be measured after multiple dose administration, reaching less than 0.1% of the lung tissue concentration. This formulation may represent a novel, easy to administer treatment modality for fungal lung infection, preventing high systemic exposure. It may also be useful as metaphylaxis to prevent the outbreak of aspergillosis in colonized animals.

Abstract 413: Myeloperoxidase-mediated Methionine Oxidation Renders Apolipoprotein A-I Amyloidogenic

Background

Elevated plasma levels of apolipoprotein A-I (apoA-I) correlate with cardiovascular health, while dysfunctional apoA-I promotes atherosclerosis. The high concentration of myeloperoxidase (MPO) produced by activated macrophages in the atherosclerotic lesions generates an oxidative environment that impacts apoA-I and reduces its antiatherogenic functions.

Recent clinical studies revealed that amyloid deposition in the atherosclerotic plaques increases with aging. Interestingly, apoA-I was identified as a central component of these atherosclerosis-related amyloids.

Hypothesis

In this study, we tested the hypothesis that MPO-mediated oxidation of apoA-I can produce protein variants that are structurally destabilized and amyloidogenic.

Methods

Plasma apoA-I purified from normal individuals was exposed to chemical (hydrogen peroxide) and enzymatic (MPO-H 2 O 2 -chloride system) oxidation. Oxidized apoA-I was incubated at 37 °C and pH 6.0 to induce fibril formation.

Results

While no fibril formation was detected in intact apoA-I, both chemically and enzymatically oxidized apoA-I produced fibrillar amyloids after 12 h incubation at 37 °C. A large molar excess (~1000:1) of H 2 O 2 was needed to generate apoA-I fibrils, whereas exposure of apoA-I to a 1:1 oxidant:apoA-I molar ratio in the presence of MPO was sufficient to confer amyloidogenic properties to the protein. Analysis by gel electrophoresis, CD spectroscopy and mass spectrometry of soluble oxidized protein and of isolated fibrils indicate that no significant protein degradation occurred upon oxidation (both chemical and enzymatic) or fibril formation. The amyloid fibrils were composed of full-length apoA-I with all three native methionines converted to methionine sulfoxide.

Conclusions

In contrast to hereditary amyloidosis wherein specific mutations of apoA-I cause protein destabilization and amyloid deposition, oxidative conditions similar to those promoted by local inflammation in atherosclerosis are sufficient to transform full-length wild-type apoA-I into an amyloidogenic protein. Thus MPO-mediated oxidation may be implicated in the mechanism that leads to amyloid fibril deposition in the atherosclerotic plaques in vivo .

Sister chromatid exchange in Greenleg Partridge and Polbar hens covered by the gene-pool protection program for farm animals in Poland

A basic assay that detects genotoxic DNA damage disrupting DNA replication and repair mechanisms is the sister chromatid exchange test. The frequency of sister chromatid exchanges was analyzed in chromosomes of the following hen breeds: Greenleg Partridge and Polbar. Chromosome preparations were obtained from our in vitro culture of peripheral blood lymphocytes stained using the fluorescence plus Giemsa (FPG) technique. The sister chromatid exchange (SCE)/cell mean of the hens under analysis was 7.83 ± 1.76 (7.22 ± 1.70 in the Greenleg Partridge and 8.43 ± 1.61 in the Polbar population). Statistically significant differences were identified between the hen breeds. A higher mean number of SCE/cell was observed in the group of hens producing fewer eggs (8.55 ± 1.51) compared with the group with a better egg yield (7.10 ± 1.65). The differences were statistically significant. Additionally, SCE frequency in the first, second, and third chromosome was analyzed in detail. The highest number of SCE was observed in the first and the lowest in the third chromosome. The SCE distribution in the particular regions of the analyzed chromosomes was also studied. The most numerous exchanges were observed in the proximal region, followed by the interstitial and distal areas.

Compromised mitochondrial fatty acid synthesis in transgenic mice results in defective protein lipoylation and energy disequilibrium

A mouse model with compromised mitochondrial fatty acid synthesis has been engineered in order to assess the role of this pathway in mitochondrial function and overall health. Reduction in the expression of mitochondrial malonyl CoA-acyl carrier protein transacylase, a key enzyme in the pathway encoded by the nuclear Mcat gene, was achieved to varying extents in all examined tissues employing tamoxifen-inducible Cre-lox technology. Although affected mice consumed more food than control animals, they failed to gain weight, were less physically active, suffered from loss of white adipose tissue, reduced muscle strength, kyphosis, alopecia, hypothermia and shortened lifespan. The Mcat-deficient phenotype is attributed primarily to reduced synthesis, in several tissues, of the octanoyl precursors required for the posttranslational lipoylation of pyruvate and α-ketoglutarate dehydrogenase complexes, resulting in diminished capacity of the citric acid cycle and disruption of energy metabolism. The presence of an alternative lipoylation pathway that utilizes exogenous free lipoate appears restricted to liver and alone is insufficient for preservation of normal energy metabolism. Thus, de novo synthesis of precursors for the protein lipoylation pathway plays a vital role in maintenance of mitochondrial function and overall vigor.

DESCRIPTION OF A NEW NAVICULOID DIATOM GENUS MORENEIS GEN. NOV. (BACILLARIOPHYCEAE) FROM SAND FLATS IN KOREA(1)

This article describes a new diatom genus Moreneis from the Yellow Sea sand flats on the west coast of Korea. The new genus is characterized by a unique combination of morphological characteristics, including the shape of the plastids, which have not been previously observed in diatoms. The valve morphology resembles other genera belonging to Lyrellaceae, within which we place this genus. In terms of areolae structure, Moreneis resembles Petroneis and Placoneis; however, it differs from both genera with respect to the raphe system and plastid shape. Cells of Moreneis spp. have a single large plastid appressed to the girdle of the secondary side of the valve, with two lobes extended toward the primary side of the valve. Furthermore, the unique feature of Moreneis frustules is the raphe, which has both external central and apical endings bent in opposite directions. We differentiated four taxa, which we describe as new for science. However, based on our findings, several established species from Navicula should also be formally transferred to Moreneis, including N. alpha Cleve, N. besarensis Giffen, N. epsilon Cleve, N. menaiana Hendey, N. polae Heiden, and N. quadri-undulata F. Meister. Analysis of published data revealed that species belonging to Moreneis are numerous in tropical marine littoral waters, and in moderate climate zones, especially in the western Pacific, with only a few species occurring in the Mediterranean and Atlantic.

Paraoxonase gene polymorphism and the risk for Alzheimer's disease in the polish population

BACKGROUND

The relationship between different paraoxonase (PON) gene polymorphisms and the risk of Alzheimer's disease (AD) was studied several times and the results were controversial.

METHODS

We investigated the association of 4 single-nucleotide polymorphisms (SNPs) of the PON1 (M55L; Q192R; -161C/T) and the PON2 (C311S) genes that were shown to affect the risk of sporadic AD. We studied 360 Caucasian cases with late-onset AD and 354 nondemented controls.

RESULTS

No significant differences were observed between the studied PON SNPs and AD risk. The results did not change after stratification of the apolipoprotein E status. Meta-analyses of studies in Caucasians assessing the associations between the PON1 M55L, -161C/T and Q192R SNPs and the risk of AD were performed, and no associations were found.

CONCLUSION

Our results suggest that the studied PON1 and PON2 polymorphisms are not associated with late-onset AD.

Quantitative trait loci associated with the humoral innate immune response in chickens were confirmed in a cross between Green-Legged Partridgelike and White Leghorn

Natural antibodies (NA) create a crucial barrier at the initial steps of the innate humoral immune response. The main role of NA in the defense system is to bind the pathogens at early stages of infection. Different pathogens are recognized by the presence of highly conserved antigen determinant [e.g., lipopolysaccharide (LPS) in gram-negative bacteria or lipoteichoic acid (LTA) in gram-positive bacteria]. In chickens, a different genetic background of NA binds LPS and LTA antigens, encoded by different QTL. The main objective of this work was to confirm known QTL associated with LPS and LTA NA. For this purpose a chicken reference population was created by crossing 2 breeds: a commercial layer, White Leghorn, and a Polish indigenous chicken, Green-Legged Partridgelike. The chromosomal regions analyzed harbored to GGA3, GGA5, GGA6, GGA8, GGA9, GGA10, GGA14, GGA15, GGA18, and GGAZ. The data collected consisted of the NA titers binding LPS and LTA (determined by ELISA at 12 wk of age) as well as the genotypes (30 short tandem repeat markers; average of 3 markers/chromosome, collected for generations F(0), F(1), and F(2)). The analyses were performed with 3 statistical models (paternal and maternal half-sib, line cross, and linkage analysis and linkage disequilibrium) implemented in GridQTL software (http://www.gridqtl.org.uk/). The QTL study of humoral innate immune response traits resulted in the confirmation of 3 QTL associated with NA titers binding LPS (located on GGA9, GGA18, and GGAZ) and 2 QTL associated with NA titers binding LTA (located on GGA5 and GGA14). A set of candidate genes within the regions of the validated QTL has been proposed.

Mammalian ACSF3 protein is a malonyl-CoA synthetase that supplies the chain extender units for mitochondrial fatty acid synthesis

The objective of this study was to identify a source of intramitochondrial malonyl-CoA that could be used for de novo fatty acid synthesis in mammalian mitochondria. Because mammalian mitochondria lack an acetyl-CoA carboxylase capable of generating malonyl-CoA inside mitochondria, the possibility that malonate could act as a precursor was investigated. Although malonyl-CoA synthetases have not been identified previously in animals, interrogation of animal protein sequence databases identified candidates that exhibited sequence similarity to known prokaryotic forms. The human candidate protein ACSF3, which has a predicted N-terminal mitochondrial targeting sequence, was cloned, expressed, and characterized as a 65-kDa acyl-CoA synthetase with extremely high specificity for malonate and methylmalonate. An arginine residue implicated in malonate binding by prokaryotic malonyl-CoA synthetases was found to be positionally conserved in animal ACSF3 enzymes and essential for activity. Subcellular fractionation experiments with HEK293T cells confirmed that human ACSF3 is located exclusively in mitochondria, and RNA interference experiments verified that this enzyme is responsible for most, if not all, of the malonyl-CoA synthetase activity in the mitochondria of these cells. In conclusion, unlike fungi, which have an intramitochondrial acetyl-CoA carboxylase, animals require an alternative source of mitochondrial malonyl-CoA; the mitochondrial ACSF3 enzyme is capable of filling this role by utilizing free malonic acid as substrate.

DIATOMS (BACILLARIOPHYTA) OF ISOLATED ISLANDS: NEW TAXA IN THE GENUS NAVICULA SENSU STRICTO FROM THE GALáPAGOS ISLANDS(1)

The diatoms (Bacillariophyta) from a coastal lagoon from the Diablas wetlands (Isla Isabela, the Galápagos Islands) were studied in material from surface samples and a sediment core spanning the past 2,700 years in order to examine evidence of diatom evolution under geographic isolation. The total number of taxa found was ∼100. Ultrastructural variation in valve morphology between members of Galápagos taxa was used to describe 10 species from the genus Navicula sensu stricto, which are new to science. Four taxa: N. isabelensis, N. isabelensoides, N. isabelensiformis, and N. isabelensiminor, shared several key characteristics that may be indicative of a common evolutionary heritage; these species therefore provide possible evidence for the in situ evolution of diatoms in the Galápagos coastal lagoons. Shared morphological characteristics include: (i) stria patterning in the central area, (ii) an elevated and thickened external raphe-sternum, (iii) external central raphe endings that are slightly deflected toward the valve primary side, and (iv) an arched valve surface. To explain these findings, two models were proposed. The first suggested limited lateral diatomaceous transport of Navicula species between the Galápagos and continental South America. Alternatively, these new species may be ecological specialists arising from the unique environmental conditions of the Galápagos coastal lagoons, which restrict the colonization of common diatom taxa and enable the establishment of novel, rare species. The Diablas wetlands are an important site for diatom research, where local-scale environmental changes have combined with global-scale biogeographic processes resulting in unique diatom assemblages.

In silico analysis of candidate genes associated with humoral innate immune response in chicken

Background

Production and function of natural antibodies (NAbs) constitutes an important mechanism of the humoral innate immunity in vertebrates. The level of NAbs in chicken is heritable and the genetic background has been partly investigated. However, to date the genetic determination of humoral innate immune response in avian species has not been fully described. The goal of this study was to propose a new set of candidate genes with a potential effect on the NAb phenotype for further SNP association study.

Methods

In silico analysis of positional and functional candidate genes covered 14 QTL regions associated with LPS, LTA & KLH NAbs and located on six chromosomes: GGA5, GGA6, GGA9, GGA14, GGA18 and GGAZ. The function of the genes was subsequently determined based on the NCBI, KEGG, Gene Ontology and InnateDB databases.

Results

As a result, the core panel of 38 genes participating in metabolic pathways of innate immune response was proposed. Most of them were assigned to chromosomes: GGA14, GGA5, GGA6 and GGAZ (13, 9, 8 and 5 genes, respectively). These candidate genes encode proteins predicted to play a role in (i) proliferation, differentiation and function of B lymphocytes; (ii) TLR signalling pathway, and (iii) MAP signalling cascade.

Conclusions

Proposed set of candidate genes is recommended to be included in the follow-up studies to model genetic networks of innate humoral immune response in chicken.

A quantitative trait locus for a primary antibody response to keyhole limpet hemocyanin on chicken chromosome 14--confirmation and candidate gene approach

A QTL involved in the primary antibody response toward keyhole limpet hemocyanin (KLH) was detected on chicken chromosome 14 in the experimental population, which was created by crossing commercial White Leghorn and a Polish native chicken breed (green-legged partridgelike). The current QTL location is a validation of previous experiments pointing to the same genomic location for the QTL linked to a primary antibody response to KLH. An experimental population was typed with microsatellite markers distributed over the chicken chromosome 14. Titers of antibodies binding KLH were measured for all individuals by ELISA. Statistical models applied in the Grid QTL Web-based software were used to analyze the data: a half-sib model, a line-cross model, and combined analysis in a linkage disequilibrium and linkage analysis model. Candidate genes that have been proposed were genotyped with SNP located in genes exons. Statistical analyses of single SNP associations were performed pointing out 2 SNP of an axis inhibitor protein (AXIN1) gene as significantly associated with the trait of an interest.