Bioinformatics Analysis of JAZF1 Gene in Broilers with Ascites Syndrome

Pulmonary vascular remodeling (PVR) is the main characteristic lesion of ascites syndrome (AS) in broilers. JAZF1 plays an important role in PVR, but there is no study on its protein function and structure. In this study, the physical and chemical properties, hydrophilicity/hydrophobicity and transmembrane domain, phosphorylation site and glycosylation site, subcellular localization and signal peptide, secondary and tertiary structure, antigen peptide and conserved domain and phylogenetic relationship of JAZF1 protein were predicted online by bioinformatics tools. The results showed that the number of amino acids of JAZF1 was 243aa, the theoretical isoelectric point was 8.63, the instability index was 58.1, and the average coefficient of hydrophilicity was -0.674. It was found to be a hydrophilic protein having 35 phosphorylation sites and a N-glycosylation site with no transmembrane domain. The protein is expressed in the nucleus, there is no signal peptide distribution in the whole sequence and the secondary structure is mainly composed of random coil and α- helix. There were 7 B cell epitopes, 7 conserved domains and compared with other birds, JAZF1 is 95.61% similar. In summary, from the analysis we came to conclude that the amino acid sequence 64-80aa, 91-108aa, 136-151aa and 179-187aa can be selected as antigen sites and among which 136-151aa may be the best. This study lays a good foundation for follow-up experiments, which then provides powerful conditions for pathological detection of pulmonary vascular remodeling and gene drug therapy of ascites syndrome in broilers.

Identification and validation of quantitative trait loci for ascites syndrome in broiler chickens using whole genome resequencing.

Background Ascites syndrome is a hypertensive, multifactorial, multigene trait affecting meat-type chickens imposing significant economic losses on the broiler industry. A region containing the CPQ gene has been previously identified as significantly affecting ascites phenotype. The region was discovered through whole genome resequencing focused on chicken chromosome 2. The association was confirmed through further genotyping in multiple broiler populations. Results The whole genome resequencing analyses have now been extended to the current chicken genome assembly. DNA samples were pooled according to gender and phenotype and the pools subjected to next generation sequencing. Loci were identified as clusters of single nucleotide polymorphisms where frequencies of the polymorphisms differed between resistant and susceptible chickens. The chickens are an unselected line descended from a commercial elite broiler line. Regions identified were specific to one or both genders. The data identify a total of 28 regions as potential quantitative trait loci for ascites. The genes from these regions have been associated with hypertensive-related traits in human association studies. One region on chicken chromosome 28 contains the LRRTM4 gene. Additional genotyping for the LRRTM4 region demonstrates an epistatic interaction with the CPQ region for ascites phenotype. Conclusions The 28 regions identified were not previously identified in a multi-generational genome wide association study using 60k Single Nucleotide Polymorphism panels. This work demonstrates the utility of whole genome resequencing as a cost effective, direct, and efficient method for identifying specific gene regions affecting complex traits. The approach is applicable to any organism with a genome assembly and requires no a priori assumptions.

Identification and validation of quantitative trait loci for ascites syndrome in broiler chickens using whole genome resequencing.

Background Ascites syndrome is a hypertensive, multifactorial, multigene trait affecting meat-type chickens imposing significant economic losses on the broiler industry. A region containing the CPQ gene has been previously identified as significantly affecting ascites phenotype. The region was discovered through whole genome resequencing focused on chicken chromosome 2. The association was confirmed through further genotyping in multiple broiler populations. Results The whole genome resequencing analyses have now been extended to the current chicken genome assembly. DNA samples were pooled according to gender and phenotype and the pools subjected to next generation sequencing. Loci were identified as clusters of single nucleotide polymorphisms where frequencies of the polymorphisms differed between resistant and susceptible chickens. The chickens are an unselected line descended from a commercial elite broiler line. Regions identified were specific to one or both genders. The data identify a total of 28 regions as potential quantitative trait loci for ascites. The genes from these regions have been associated with hypertensive-related traits in human association studies. One region on chicken chromosome 28 contains the LRRTM4 gene. Additional genotyping for the LRRTM4 region demonstrates an epistatic interaction with the CPQ region for ascites phenotype. Conclusions The 28 regions identified were not previously identified in a multi-generational genome wide association study using 60k Single Nucleotide Polymorphism panels. This work demonstrates the utility of whole genome resequencing as a cost effective, direct, and efficient method for identifying specific gene regions affecting complex traits. The approach is applicable to any organism with a genome assembly and requires no a priori assumptions.