Associations between two novel rSNPs in 5'-flanking region of the bovine casein gene cluster and milk performance traits

Ten evolutionary conservative sequences with high identity level to homological sequences in other mammal species were revealed in 5'-flanking region of casein's genes cluster. Five novel SNPs located inside of the evolutionary conservative regions were identified. The binding sites were revealed to be present in one allelic variant of four detected SNPs. So these SNPs were considered as rSNPs. Significant differences of allelic frequencies were revealed between beef cow's group and dairy cow's group in two rSNPs (NCE4, NCE7, p<0.001). Different alleles of those two rSNPs were shown to be associated with some milk performance traits in Black-and-White Holstein dairy cows. Significant difference of protein percentage has been found between cows with G/G and A/A genotypes (P<0.05) and A/G and A/A genotypes (P<0.05) for NCE4 polymorphism. The groups of animals with genotypes G/G and A/G for NCE7 polymorphism were significantly different in milk yield at the first lactation (kg) (P<0.01), milk fat yield (kg) (P<0.05) and milk protein yield (kg) (P<0.01). For the last trait the difference was significant also between cows with genotypes G/G and A/A for rSNP NCE7 (P<0.05).     

Solution structure of NEMO zinc finger and impact of an anhidrotic ectodermal dysplasia with immunodeficiency-related point mutation

The regulatory NEMO (NF-κB essential modulator) protein has a crucial role in the canonical NF-κB signaling pathway notably involved in immune and inflammatory responses, apoptosis and oncogenesis. The regulatory domain is located in the C-terminal half of NEMO and contains a classical CCHC-type zinc finger (ZF). We have investigated the structural and functional effects of a cysteine to phenylalanine point mutation (C417F) in the ZF motif, identified in patients with anhidrotic ectodermal dysplasia with immunodeficiency. The solution structures of the wild type and mutant ZF were determined by NMR. Remarkably, the mutant adopts a global ββα fold similar to that of the wild type and retains thermodynamic stability, i.e., the ability to bind zinc with a native-like affinity, although the last zinc-chelating residue is missing. However, the mutation induces enhanced dynamics in the motif and leads to an important loss of stability. A detailed analysis of the wild type solution structure and experimental evidences led to the identification of two possible protein-binding surfaces that are largely destabilized in the mutant. This is sufficient to alter NEMO function, since functional complementation assays using NEMO-deficient pre-B and T lymphocytes show that full-length C417F pathogenic NEMO leads to a partial to strong defect in LPS, IL-1β and TNF-α-induced NF-κB activation, respectively, as compared to wild type NEMO. Altogether, these results shed light onto the role of NEMO ZF as a protein-binding motif and show that a precise structural integrity of the ZF should be preserved to lead to a functional protein-recognition motif triggering full NF-κB activation.     

Karyotypic characterization and genomic organization of the 5S rDNA in <Emphasis Type="Italic">Polypterus senegalus</Emphasis> (Osteichthyes,Polypteridae)

Polypteridae (Cladistia) is a family of archaic fishes, confined to African freshwaters. On account of their primitiveness in anatomical and morphological characters and mosaic relationships among lower Osteichthyans fishes, they constitute an important subject for the study of evolution in vertebrates. Very little is known about the karyological structure of these species. In this article, a cytogenetic analysis on twenty specimens of Polypterus senegalus (Cuvier, 1829) was performed using both classical and molecular techniques. Karyotype (2n = 36; FN = 72), chromosome location of telomeric sequences (TTAGGG) _n , (GATA)₇ repeats and ribosomal 5S and 18S rRNA genes were examined by using Ag-NOR, classical C-banding, CMA₃ staining and FISH. Staining with Ag-NOR showed the presence of two GC rich NORs on the p arm of the chromosome pair no. 1. CMA₃ marked all centromerical and some (no. 1 and no. 14) telomeric regions. FISH with 5S rDNA marked the subtelomeric region of the q arm of the chromosome pair no. 14. FISH with 18S rDNA marked the telomeric region of the p arm of the chromosome pair no. 1, previously marked by Ag-NOR. (GATA)₇ repeats marked the subtelomeric regions of all chromosome pairs, with the exclusion of the no. 1, 3 and 14. Hybridization with telomeric probes (TTAGGG) _n showed bright signals at the end of all chromosomes. After cloning, the 5SrDNA alignment revealed an organization of sequences made up of two different classes of tandem arrays (5S type I and 5S type II) of different lengths.     

Isolation and characterization of 16 tetranucleotide microsatellite loci in the red panda (Ailurus fulgens)

A total of 15 polymorphic tetranucleotide microsatellite loci in the red panda, Ailurus fulgens, were characterized in this study. Based on evaluations of 33 red pandas, the number of observed alleles for each locus ranged from seven to 17 and the expected and observed heterozygosities were 0.412–0.897 and 0.121–0.909, respectively. The mean polymorphic information content was 0.721. These markers would greatly strengthen the utilization of microsatellite tools in genetic variation studies in red panda populations.     

Human Pancreatic Tumor Organoids Reveal Loss of Stem Cell Niche Factor Dependence during Disease Progression

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