Expression of androgen and estrogen receptors in the testicular tissue of chickens, quails and chicken-quail hybrids

36 New Roman cocks, 30 Korean male quails and 30 chicken-quail hybrids of different day-age were selected and their body weight and testes weights were measured and as well, their testes were collected. Real-time polymerase chain reaction (RT-PCR) was performed to evaluate the messenger ribonucleic acid (mRNA) expression patterns of androgen receptors (AR) and estrogen receptors (ER) genes in testicular tissue of chickens, quails and chicken-quail hybrids at different growth stages. The results show that the testes of chickens and quails grew and developed normally with body weight gain, but the testes of chicken-quail hybrids had a slower growth rate and stunted growth. Real-time PCR showed AR and ER mRNA expression patterns in testes of chickens and quails at different growth stages were similar. AR mRNA expression in chickens and quails reached a significant peak at 80 and 30 days of age, respectively and their ER gene expression showed fluctuation slightly. The AR and ER expression of chicken-quail hybrids were different from the above expression patterns; the hybrids AR gene expression showed a gradual decline and ER gene expression gradually increased. The chickenquail hybrids AR and ER gene expression was abnormal and we speculate this is an important molecular factor for the testicular dysplasia of chicken-quail hybrids. Our results show that AR gene expression was upregulated by ER gene and we suggest that the synergetic effect of AR and ER gene regulated the normal testis growth and development of chicken and quail.Keywords: Chicken, quail, chicken-quail hybrid, testis, androgen receptors (AR), estrogen receptors (ER) expressionAfrican Journal of Biotechnology Vol. 11(29), pp. 7344-7353, 10 April, 201

Circular RNA expression profiles in the porcine liver of two distinct phenotype pig breeds

Objective An experiment was conducted to identify and characterize the circular RNA expression and metabolic characteristics in the liver of Jinhua pigs and Landrace pigs. Methods Three Jinhua pigs and three Landrace pigs respectively at 70-day were slaughtered to collect the liver tissue samples. Immediately after slaughter, blood samples were taken to detect serum biochemical indicators. Total RNA extracted from liver tissue samples were used to prepare the library and then sequence on HiSeq 2500. Bioinformatic methods were employed to analyze sequence data to identify the circRNAs and predict the potential roles of differentially expressed circRNAs between the two breeds. Results Significant differences in physiological and biochemical traits were observed between growing Jinhua and Landrace pigs. We identified 84,864 circRNA candidates in two breeds and 366 circRNAs were detected as significantly differentially expressed. Their host genes are involved in lipid biosynthetic and metabolic processes according to the gene ontology analysis and associated with metabolic pathways. Conclusion Our research represents the first description of circRNA profiles in the porcine liver from two divergent phenotype pigs. The predicted miRNA-circRNA interaction provides important basis for miRNA-circRNA relationships in the porcine liver. These data expand the repertories of porcine circRNA and are conducive to understanding the possible molecular mechanisms involved in miRNA and circRNA. Our study provides basic data for further research of the biological functions of circRNAs in the porcine liver

Combined analysis of data from two granddaughter designs: A simple strategy for QTL confirmation and increasing experimental power in dairy cattle

A joint analysis of five paternal half-sib Holstein families that were part of two different granddaughter designs (ADR- or Inra-design) was carried out for five milk production traits and somatic cell score in order to conduct a QTL confirmation study and to increase the experimental power. Data were exchanged in a coded and standardised form. The combined data set (JOINT-design) consisted of on average 231 sires per grandsire. Genetic maps were calculated for 133 markers distributed over nine chromosomes. QTL analyses were performed separately for each design and each trait. The results revealed QTL for milk production on chromosome 14, for milk yield on chromosome 5, and for fat content on chromosome 19 in both the ADR- and the Inra-design (confirmed within this study). Some QTL could only be mapped in either the ADR- or in the Inra-design (not confirmed within this study). Additional QTL previously undetected in the single designs were mapped in the JOINT-design for fat yield (chromosome 19 and 26), protein yield (chromosome 26), protein content (chromosome 5), and somatic cell score (chromosome 2 and 19) with genomewide significance. This study demonstrated the potential benefits of a combined analysis of data from different granddaughter designs

Association of PPARγ2 polymorphisms with carcass and meat quality traits in a Pietrain x Jinhua F2 population

The PPARγ2 gene is a key regulator of both proliferation and preadipocyte differentiation in mammals. Herein its genotype and allele frequencies were analyzed using PCR-SSCP in eight pig breeds (N = 416). Two kinds of polymorphisms of the PPARγ2 gene were detected, including a previously reported shift SNP A177G (Met59Val) in exon 1 and a novel silent mutation G876A in exon 5. The results revealed that European pig breeds carry a higher allele A frequency at the A177G locus and a fixed GG genotype at the G876A locus. Allele A at the G876A locus was only found in Jinhua pigs. The association between haplotype (A177G/G876A) and carcass and meat quality traits was analyzed in a Pietrain x Jinhua F2 population (N = 248). The PPARγ2 gene was found to be significantly associated with backfat thickness at the shoulder (p < 0.05), 6–7th ribs (p < 0.01), last rib (p < 0.01), gluteus medius (p <0.05) and ham weight (p < 0.01). Significant effects of different haplotypes on ham weight and backfat thickness at the 6–7th ribs, last rib, and gluteus medius were also observed

Expression Analysis of the PITX2 Gene and Associations between Its Polymorphisms and Body Size and Carcass Traits in Chickens

PITX2 is expressed in and plays an important role in myocytes of mice, and it has effects on late myogenic differentiation in chickens. However, the expression profile and polymorphisms of PITX2 remain unclear in chickens. Therefore, the aim of the present study was to detect its expression and investigate single nucleotide polymorphisms (SNPs) within its exons and then to evaluate whether these polymorphisms affect body size as well as carcass traits in chickens. The expression analysis showed that the expression level of chicken PITX2 mRNA in the leg muscle and hypophysis was significantly higher (p &lt; 0.01) than those in other tissues. The results of polymorphisms analysis identified two SNPs (i.e., g.9830C &gt; T and g.10073C &gt; T) in exon 1 and 10 SNPs (i.e., g.12713C &gt; T, g.12755C &gt; T, g.12938G &gt; A, g. 3164C &gt; T, g.13019G &gt; A, g.13079G &gt; A, g.13285G &gt; A, g.13335G &gt; A, g.13726A &gt; G and g.13856C &gt; T) in exon 3, including four novel SNPs (i.e., g.9830C &gt; T, g.12713C &gt; T, g.12938G &gt; A and g.13856C &gt; T). In the loci of g.10073C &gt; T and g.12713C &gt; T, chickens with the CT genotype had the highest (p &lt; 0.05 or p &lt; 0.01) breast depth and breast angle, respectively. For the locus of g.13335G &gt; A, chickens with the GG genotype had the highest (p &lt; 0.05 or p &lt; 0.01) breast angle and shank circumference. For the locus of g.13726A &gt; G, chickens with the GG genotype had the highest breast width, fossil keel bone length and shank circumference. The locus of g.12713A &gt; G had significant effects on the PITX2 mRNA expression level in leg muscle. The H1H7 diplotype showed the highest shank circumference, and the H2H8 diplotype showed the highest breast muscle rate. The present research suggested that polymorphisms of the exons of the PITX2 gene were significantly associated with the body size and carcass traits of Wuliang Mountain Black-bone chickens and the PITX2 gene could be a potential candidate gene for molecular marker-aided selection in Wuliang Mountain Black-bone chickens and other chicken breeds

Primary Genetic Investigation of a Hyperlipidemia Model: Molecular Characteristics and Variants of the Apolipoprotein E Gene in Mongolian Gerbil

The objective of this work was to establish a novel Mongolian gerbil (Meriones unguiculatus) hyperlipidemia model and to investigate its susceptibility genetic basis. Two rodent (gerbil and rat) hyperlipidemia models were induced by feeding a high fat/high-cholesterol (HF/HC) diet. There were significant increases of serum total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in gerbils within a 4-week modeling period. About 10–30% of >8-month-old individuals developed hyperlipidemia spontaneously. The apolipoprotein E (ApoE) gene was cloned by merging a sequence of rapid amplification of cDNA ends (RACE) and nested polymerase chain reaction products. The results revealed an open reading frame of 948 bp, encoding a protein of 298 amino acids. The gene without a 5′-UTR region in the first intron was highly homologous to human Apo-A-I and rat Apo-A-IV. The distribution of expression of the ApoE gene in liver, brain, heart, lung, kidney, and adrenal gland was detected by an ABC immunohistochemical procedure. Three single nucleotide polymorphisms (SNPs; C97T, G781T, and A1774T) were first found using PCR-single-strand conformation polymorphism (PCR-SSCP) in a closed population containing 444 animals. Correlation analysis confirmed that new SNPs , age, and gender were associated significantly (P<0.05) with hyperlipidemia

Chronological Expression of <i>PITX2</i> and <i>SIX1</i> Genes and the Association between Their Polymorphisms and Chicken Meat Quality Traits

Meat quality is closely related to the development of skeletal muscle, in which PITX2 and SIX1 genes play important regulatory roles. The present study firstly provided the data of chronological expression files of PITX2 and SIX1 genes in the post-hatching pectoral muscle and analyzed the association of their polymorphisms with the meat quality traits of Wuliang Mountain Black-bone (WLMB) chickens. The results showed that both PITX2 and SIX1 genes were weakly expressed in the second and third weeks, and then increased significantly from the third week to the fourth week. Furthermore, there was a significant positive correlation between the expression levels of the two genes. Twelve and one SNPs were detected in the chicken PITX2 and SIX1 genes, respectively, of which four SNPs (g.9830C > T, g.10073C > T, g.13335G > A, g.13726A > G) of the PITX2 gene and one SNP (g.564G > A) of the SIX1 gene were significantly associated with chicken meat quality traits. For the PITX2 gene, chickens with the CT genotype of g.9830C > T showed the highest meat color L*, shear force (SF), pH, and the lowest electrical conductivity (EC), and drip loss (DL) (p p T had the lowest L*, pH, and the highest DL (p A had the highest (p < 0.05) SF and pH. Furthermore, pH had a significant correlation with all the other meat quality traits. The current study could contribute to the research of regulatory mechanisms of meat quality and lay the foundation for improving meat quality based on marker-assisted selection in chickens