DNA sequence of melanocortin 1-receptor gene in Coturnix japonica: Correlation with three E locus alleles—E,e+, and erh

The melanocortin 1-receptor (MC1-R) gene plays a key role in the expression of fur and feather color in mammals and birds by regulating the distribution of two melanin pigments: eumelanin (black/brown) and pheomelanin (red/yellow). MC1-R corresponds to the classical Extension (E) locus in mice, pigs, dogs, horses, and chickens. Three E locus alleles, the wild-type (e+), brown (E), and redhead (erh) have been identified in Japanese quail (Coturnix japonica). To determine if the quail E locus phenotypes were due to variation in the MC1-R gene, the coding region of the MC1-R gene was PCR amplified and DNA sequenced using genomic DNA isolated from individuals exhibiting the phenotypes of the three quail alleles. The DNA sequence comparison revealed two missense mutations that differentiated the brown from the wild-type and redhead quail. A single-base substitution resulted in a Val58Ile change, and another single-base substitution produced a Glu92Lys change in the brown quail. The redhead quail sequence carried a seven-base deletion extending from nucleotide position 682 to 688, resulting in a reading frame shift and premature termination of the MC1-R gene after amino acid position 231. The Glu92Lys change in the brown allele created a Msc I restriction fragment length polymorphism (RFLP). A PCR-Msc I RFLP test was developed and a direct correspondence between phenotype and genotype was found by testing the DNA of a population segregating for the brown and wild-type alleles. The DNA sequence and segregation data indicate that the quail E locus is homologous to the E locus identified in other birds and mammals

The S phase checkpoint promotes the Smc5/6 complex dependent SUMOylation of Pol2, the catalytic subunit of DNA polymerase ε

Replication fork stalling and accumulation of single-stranded DNA trigger the S phase checkpoint, a signalling cascade that, in budding yeast, leads to the activation of the Rad53 kinase. Rad53 is essential in maintaining cell viability, but its targets of regulation are still partially unknown. Here we show that Rad53 drives the hyper-SUMOylation of Pol2, the catalytic subunit of DNA polymerase ε, principally following replication forks stalling induced by nucleotide depletion. Pol2 is the main target of SUMOylation within the replisome and its modification requires the SUMO-ligase Mms21, a subunit of the Smc5/6 complex. Moreover, the Smc5/6 complex co-purifies with Pol ε, independently of other replisome components. Finally, we map Pol2 SUMOylation to a single site within the N-terminal catalytic domain and identify a SUMO-interacting motif at the C-terminus of Pol2. These data suggest that the S phase checkpoint regulate Pol ε during replication stress through Pol2 SUMOylation and SUMO-binding abilit

Characterization of the Genetic Status of Populations of Red Junglefowl

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Proteomic Changes in the Plasma of Broiler Chickens with Femoral Head Necrosis

Femoral head necrosis (FHN) is a skeletal problem in broiler chickens, where the proximal femoral head cartilage shows susceptibility to separation from its growth plate. The selected birds with FHN showed higher body weights and reduced plasma cholesterol. The proteomic differences in the plasma of healthy and FHN-affected chickens were explored using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) and liquid chromatography/electrospray ionization-tandem mass spectrometry (LC-MS/MS) to prospect for protein biomarkers. We isolated two differentially expressed low molecular weight proteins and identified them by MALDI peptide mass fingerprinting as fibrinogen- and fetuinderived peptides, respectively. These peptides were reduced in birds susceptible to femoral head problems. Quantitation of LC-MS/MS spectra showed elevated levels of gallinacin-9, apolipoprotein A1, and hemoglobin and reduced levels of alpha-1-acid glycoprotein, albumin, and SPINK7 proteins in FHN. These results suggest that the bodyweight and the lipid profiles along with the above proteins can be useful as noninvasive biomarkers of FHN