Hydroxymethylbilane synthase (HMBS) gene-based endogenous internal control for avian species

Identification of reference genes for studies of quantitative gene expression in male and female quail tissues

In industrial poultry, quail production has gained increasing prominence over the years. It is known that the intensification of genetic studies has contributed greatly to this growth, through techniques, such as analysis of gene expression by PCR, for example. This study aimed to evaluate stability and recommend reference genes for quantitative real-time PCR in different tissues from male and female broiler quails. The stability of 10 housekeeping genes (GAPDH, RPL5, MRPS27, MRPS30, TFRC, HMBS, EEF1, LDHA, B2M, and UBC) by means Bestkeeper, NormFinder, GeNorm softwares with ΔCq method. The tissues analyzed were: heart, thigh muscle, brain, and spleen, considering that they are tissues commonly used in nutrigenomic, immunological, and poultry performance research. As expected, the reference genes tested showed varying stability depending on the tissue evaluated. According to the present study, the most stable housekeeping genes were MRPS30, TFRC, and HMBS in heart; MRPS30, EEF1, and HMBS in thigh muscle; B2M, GAPDH, and UBC in brain; and EEF1, LDHA, and HMBS in spleen. Therefore, it is recommended to be used as reference genes for gene expression studies of male and female quails.

Assessing avian leukosis virus proviral load and lesion correlates in fowl glioma-inducing virus-infected Japanese bantam chickens

The fowl glioma-inducing virus prototype (FGVp) and its variants, which belong to avian leukosis virus subgroup A (ALV-A), induce cardiomyocyte abnormalities and gliomas in chickens. However, the molecular mechanisms underlying these myocardial changes remain unclear, and ALV-induced tumorigenesis, which is caused by proviral insertional mutagenesis, does not explain the early development of cardiac changes in infected chickens. We established a quantitative PCR (qPCR) assay to measure ALV-A proviral loads in the brains and hearts of FGV-infected Japanese bantam chickens and compared these results with morphologic lesions. Four of 22 bantams had both gliomas and cardiac lesions. Hearts with cardiac lesions had a higher proviral load (10.3 ± 2.7 proviral copies/nucleus) than those without cardiac lesions (0.4 ± 0.4), suggesting that the proviral load in hearts is correlated with the frequency of myocardial changes. Our qPCR method may be useful in the study of ALV-induced cardiomyocyte abnormalities.

Identification of stable reference genes for quantitative gene expression analysis in the duodenum of meat-type ducks

Quantitative polymerase chain reaction (qPCR) is an important method to detect gene expression at the molecular level. The selection of appropriate housekeeping genes is the key to accurately calculating the expression level of target genes and conducting gene function studies. In this study, the expression of eight candidate reference genes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-actin (β-actin), 18S ribosomal RNA (18S rRNA), hydroxymethylbilane synthase (HMBS), hypoxanthine phosphoribosyltransferase 1 (HPRT1), TATA box binding protein (TBP), ribosomal protein L13 (RPL13), and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein (YWHAZ), in the duodenal epithelial tissue of 42-day-old meat-type ducks were detected using qPCR. Furthermore, their expression stability was analyzed using the geNorm, NormFinder, and BestKeeper programs. The results indicated that HMBS and YWHAZ were the most stably expressed genes. All three programs indicated that the expression of 18S rRNA was the least stable, making it unsuitable for the study of gene expression in meat-type duck tissues. This study provides stable reference genes for gene expression analysis and contributes to further studies on the gene function of meat-type ducks.