Thermal conditioning of quail embryos has transgenerational and reversible long-term effects.

Background: In the current context of global warming, thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubation temperature. However, because of their likely epigenetic origin, thermal manipulation effects may last more than one generation with consequences for the poultry industry. In this work, a multigenerational and transgenerational analysis of thermal manipulation during embryogenesis was performed to uncover the long-term effects of such procedure.

Optimization of embryonic thermal programming confirms increased liver fattening in mule ducks and changes in lipid metabolism.

The embryonic thermal programming (TM) in birds has been shown to impact several physiological parameters such as resistance to thermal stress, muscle growth or immunity. In mule ducks, it has recently been shown that TM can induce metabolic programming resulting in increased liver weight and fat storage after overfeeding. However, a decrease in hatchability and quality was also observed, suggesting that this technique needs to be optimized.

Fasting/refeeding: an experimental model to study the impact of early thermal manipulation on hepatic metabolism in mule ducks.

An increase in egg incubation temperature was previously shown to enhance the metabolism of mule ducks and increase liver fattening after overfeeding, through a metabolic programming mechanism. Here, we examined whether fasting (F) followed by refeeding (RF) in 11-wk-old mule ducks could become an accelerated model to study the mechanisms of metabolic programming following embryonic thermal manipulation. This study investigated the hepatic response of mule ducks subjected to 23 h of fasting and 1 h of refeeding, in control or thermally programmed animals (with an increase of 1°C, 16 h per day from to of embryogenesis).

Short communication: Effects of in-ovo injection of endocrine disruptors and methyltransferase inhibitor on quail growth and egg-laying performances.

Early experiences, including prenatal environment, are known to influence a wide variety of mechanisms involved in the phenotype elaboration. We investigated the effect of the addition of endocrine disruptors or of a methyltransferase inhibitor during the embryonic development of quails from different genetic backgrounds (four different quail lines) on their growth and egg-laying performances. Fifty-four pairs of parents per line were used and fertilised eggs from each pair were randomly divided into five groups: a control group without any injection, an injected control group treated by injection into the egg of sesame oil, and three groups treated by injection of Genistein, Bisphenol A or 5-Aza-2'-deoxycytidine.

Identification of different critical embryonic periods to modify egg incubation temperature in mule ducks.

Egg incubation of mule ducks, mainly used for fatty liver production, is one of the critical phases in this sector. Based on hatching rate, the best incubation parameters have already been well described for poultry, but the literature on ducks is lacking. In this study, we tested different incubation conditions by varying two important factors, temperature and relative humidity, in mule ducks.

Embryonic thermal manipulation impacts the postnatal transcriptome response of heat-challenged Japanese quails.

Background: The thermal-manipulation (TM) during egg incubation is a cyclic exposure to hot or cold temperatures during embryogenesis that is associated to long-lasting effects on growth performance, physiology, metabolism and temperature tolerance in birds. An increase of the incubation temperature of Japanese quail eggs affected the embryonic and post-hatch survival, growth, surface temperatures and blood characteristics potentially related to thermoregulation capacities. To gain new insights in the molecular basis of TM in quails, we investigated by RNA-seq the hypothalamus transcriptome of 35 days-old male and female quails that were treated by TM or not (C, control) during embryogenesis and that were exposed (HC) or not (RT) to a 36 °C heat challenge for 7 h before sampling.

Two repeated motifs enriched within some enhancers and origins of replication are bound by SETMAR isoforms in human colon cells.

Setmar is a gene specific to simian genomes. The function(s) of its isoforms are poorly understood and their existence in healthy tissues remains to be validated. Here we profiled SETMAR expression and its genome-wide binding landscape in colon tissue.

Short cold exposures during incubation and postnatal cold temperature affect performance, breast meat quality, and welfare parameters in broiler chickens.

Cold stimulations during egg incubation were reported to limit the occurrence of ascites in broilers subjected to cold temperature after 14 d of age. However, data are lacking on the impacts of such strategy in case of cold temperature conditions at start. This study aimed to evaluate the effects of incubation and posthatch cold challenge on performance, breast muscle integrity, and meat processing quality in broiler chickens.

Embryonic thermal manipulation has short and long-term effects on the development and the physiology of the Japanese quail.

In vertebrates, the embryonic environment is known to affect the development and the health of individuals. In broiler chickens, the thermal-manipulation (TM) of eggs during the incubation period was shown to improve heat tolerance at slaughter age (35 days of age) in association with several modifications at the molecular, metabolic and physiological levels. However, little is known about the Japanese quail (Coturnix japonica), a closely related avian species widely used as a laboratory animal model and farmed for its meat and eggs.

Thermal Manipulation During Embryogenesis Impacts H3K4me3 and H3K27me3 Histone Marks in Chicken Hypothalamus.

Changes in gene activity through epigenetic alterations induced by early environmental challenges during embryogenesis are known to impact the phenotype, health, and disease risk of animals. Learning how environmental cues translate into persisting epigenetic memory may open new doors to improve robustness and resilience of developing animals. It has previously been shown that the heat tolerance of male broiler chickens was improved by cyclically elevating egg incubation temperature.

Variations in genome size between wild and domesticated lineages of fowls belonging to the Gallus gallus species.

Efforts to elucidate the causes of biological differences between wild fowls and their domesticated relatives, the chicken, have to date mainly focused on the identification of single nucleotide mutations. Other types of genomic variations have however been demonstrated to be important in avian evolution and associated to variations in phenotype. They include several types of sequences duplicated in tandem that can vary in their repetition number.

Identification of Reference Genes for Quantitative Gene Expression Studies in Three Tissues of Japanese Quail.

RT-qPCR is the gold standard for candidate gene expression analysis. However, the interpretation of RT-qPCR results depends on the proper use of internal controls, i.e.

Effect of low incubation temperature and low ambient temperature until 21 days of age on performance and body temperature in fast-growing chickens.

Thermal manipulation during embryogenesis was previously reported to decrease the occurrence of ascites and to potentially improve cold tolerance of broilers. The objective of our study was to explore the effects of the interaction of cold incubation temperatures and cool ambient temperatures until 21 d of age on performance and body temperature. Ross 308 eggs were incubated either under control conditions I0 (37.

An Assessment of Fixed and Native Chromatin Preparation Methods to Study Histone Post-Translational Modifications at a Whole Genome Scale in Skeletal Muscle Tissue.

Background: Genomic loci associated with histone marks are typically analyzed by immunoprecipitation of the chromatin followed by quantitative-PCR (ChIP-qPCR) or high throughput sequencing (ChIP-seq). Chromatin can be either cross-linked (X-ChIP) or used in the native state (N-ChIP). Cross-linking of DNA and proteins helps stabilizing their interactions before analysis.

Embryonic environment and transgenerational effects in quail.

Background: Environmental exposures, for instance to chemicals, are known to impact plant and animal phenotypes on the long term, sometimes across several generations. Such transgenerational phenotypes were shown to be promoted by epigenetic alterations such as DNA methylation, an epigenetic mark involved in the regulation of gene expression. However, it is yet unknown whether transgenerational epigenetic inheritance of altered phenotypes exists in birds.

A simple PCR method for sexing Japanese quail Coturnix japonica at hatching.

1. The quail is a potentially important avian model for molecular studies; a major drawback is the inability to sex visually before 3 weeks of age. Molecular sexing is therefore an absolute requirement when animals are sampled before that age.

Thermal manipulation of the chicken embryo triggers differential gene expression in response to a later heat challenge.

Background: Meat type chickens have limited capacities to cope with high environmental temperatures, this sometimes leading to mortality on farms and subsequent economic losses. A strategy to alleviate this problem is to enhance adaptive capacities to face heat exposure using thermal manipulation (TM) during embryogenesis. This strategy was shown to improve thermotolerance during their life span.

Cyclic variations in incubation conditions induce adaptive responses to later heat exposure in chickens: a review.

Selection programs have enabled broiler chickens to gain muscle mass without similar enlargement of the cardiovascular and respiratory systems that are essential for thermoregulatory efficiency. Meat-type chickens cope with high ambient temperature by reducing feed intake and growth during chronic and moderate heat exposure. In case of acute heat exposure, a dramatic increase in morbidity and mortality can occur.

SHOOT GROWTH1 maintains Arabidopsis epigenomes by regulating IBM1.

Maintaining correct DNA and histone methylation patterns is essential for the development of all eukaryotes. In Arabidopsis, we identified SHOOT GROWTH1 (SG1), a novel protein involved in the control of gene methylation. SG1 contains both a Bromo-Adjacent Homology (BAH) domain found in several chromatin regulators and an RNA-Recognition Motif (RRM).

Quantitative modulation of polycomb silencing underlies natural variation in vernalization.

Arabidopsis thaliana accessions have adapted to growth in a wide range of climates. Variation in flowering and alignment of vernalization response with winter length are central to this adaptation. Vernalization involves the epigenetic silencing of the floral repressor FLC via a conserved Polycomb (PRC2) mechanism involving trimethylation of Lys(27) on histone H3 (H3K27me3).

Lessons from eQTL mapping studies: non-coding regions and their role behind natural phenotypic variation in plants.

Even if considerable progress has been achieved towards the understanding of natural variation in plant systems, the contribution of transcript abundance variation to phenotypic diversity remains unappreciated. Over the last decade, efforts to characterise the genome-wide expression variation in natural accessions, structured populations and hybrids have improved our knowledge of the contribution of non-coding polymorphisms to gene expression regulation. Moreover, new studies are helping to unravel the role of expression polymorphisms and their orchestrated performance.

Protocol: A simple phenol-based method for 96-well extraction of high quality RNA from Arabidopsis.

Background: Many experiments in modern plant molecular biology require the processing of large numbers of samples for a variety of applications from mutant screens to the analysis of natural variants. A severe bottleneck to many such analyses is the acquisition of good yields of high quality RNA suitable for use in sensitive downstream applications such as real time quantitative reverse-transcription-polymerase chain reaction (real time qRT-PCR). Although several commercial kits are available for high-throughput RNA extraction in 96-well format, only one non-kit method has been described in the literature using the commercial reagent TRIZOL.