Whole genome analysis of a novel neurotropic bovine astrovirus detected in a Japanese black steer with non-suppurative encephalomyelitis in Japan.

While neurotropic bovine astroviruses (BoAstVs) have been identified in North America and Europe, their presence has never been reported in Asia. In this study, we detected BoAstV in the brain of a steer showing neurological signs. Phylogenetic analysis revealed that the identified virus belongs to the Virginia/Human-Mink-Ovine clade, which contains most of the neurotropic astroviruses including the neurotropic BoAstVs. Similarity plot analysis showed that the virus was closely related to the American BoAstV NeuroS1 strain with respect to the ORF regions and to the European BoAstV CH13 strain in the 3' untranslated region, suggesting the occurrence of intra-genotypic recombination events.

Effect of dietary fermented mushroom bed on egg production in laying hens.

Egg productivity is declined by stress. It has been reported that some food supplements can improve the egg productivity due to a reduction of environmental stress. We evaluated the effect of fermented waste mushroom bed (FWMB) as a dietary additive on egg productivity. Hens were fed control food (control group, n = 100) or 3% FWMB-added food (FWMB group, n = 100) for 16 months. The number of eggs, soft-shelled eggs, and broken eggs were recorded for 15 months. We also evaluated stress-related markers (ovotransferrin, lipid peroxide, and the heterophil-to-lymphocyte ratio). The FWMB group had slightly increased egg production compared with control hens. The FWMB group produced significantly less broken and soft-shelled eggs than the control group. All stress-related markers were significantly lower in the FWMB group than in the control group. Gut flora was also affected by FWMB feeding. The increased egg production and decreased proportion of broken and soft-shelled eggs might be related to the prevention of stressful conditions by FWMB.

Morphologically abnormal beaks observed in chickens that were beak-trimmed at young ages.

A survey of beak morphological abnormalities was performed on 6,201 chickens (egg-laying hens and chickens for meat production belonging to 25 flocks) brought to a poultry processing plant. The observed abnormalities varied among flocks with occurrence rates ranging from 0.48 to 46.67%. The occurrence was high in flocks subjected to beak trimming and varied significantly according to chicken breed, with the highest rates of abnormalities in a certain chicken breed. The most widely observed abnormalities were: 1) uneven growth of the upper and lower mandibles, mostly with elongation of the lower mandible (accounting for 64.8% of all abnormalities); 2) misalignment of the upper and lower mandibles, causing lateral deviation or crossing (16.3%); 3) sharp or jagged deformities of the mandible tips (10.1%); 4) permanent open beak, a deformity in which the beak did not close completely even when closed (5.8%); and 5) formation of tubercular swellings at the tips of the upper or lower mandibles (3.1%). This is the first report on the occurrence of beak abnormalities in beak-trimmed poultry in Japan.

Transactivation of Schizosaccharomyces pombe cdt2+ stimulates a Pcu4-Ddb1-CSN ubiquitin ligase.

Cullin-4 forms a scaffold for multiple ubiquitin ligases. In Schizosaccharomyces pombe, the Cullin-4 homologue (Pcu4) physically associates with Ddb1 and the COP9 signalosome (CSN). One target of this complex is Spd1. Spd1 regulates ribonucleotide reductase (RNR) activity. Spd1 degradation during S phase, or following DNA damage of G2 cells, results in the nuclear export of the small RNR subunit. We demonstrate that Cdt2, an unstable WD40 protein, is a regulatory subunit of Pcu4-Ddb1-CSN ubiquitin ligase. cdt2 deletion stabilises Spd1 and prevents relocalisation of the small RNR subunit from the nucleus to the cytoplasm. cdt2+ is periodically transcribed by the Cdc10/DSC1 transcription factor during S phase and transiently transcribed following DNA damage of G2 cells, corresponding to Spd1 degradation profiles. Cdt2 co-precipitates with Spd1, and Cdt2 overexpression results in constitutive Spd1 degradation. We propose that Cdt2 incorporation into the Pcu4-Ddb1-CSN complex prompts Spd1 targeting and subsequent degradation and that Cdt2 is a WD40 repeat adaptor protein for Cullin-4-based ubiquitin ligase.

The cation-transporting P-type ATPase Cta4 is required for assembly of the forespore membrane in fission yeast.

A novel sporulation-deficient mutant, sev4-L5, was isolated in a genetic screen of a collection of temperature-sensitive mutants of Schizosaccharomyces pombe. The wild-type sev4 gene was identified as cta4+, which encodes a putative cation-transporting P-type ATPase. The sev4-L5 allele harbored a single missense mutation that caused replacement of Gly615 with a glutamate at the putative ATP-binding site. Similar to cta4-null mutants, sev4-L5 exhibited defects in growth at high and low temperatures, and sensitivity to high and extremely low concentrations of Ca2+. The cta4+ mRNA level was considerably enhanced during meiosis. When sev4-L5 cells were incubated in sporulation medium at the permissive temperature, meiotic nuclear divisions proceeded with normal kinetics, but spores were not formed. Structural alteration of the spindle pole body, which is prerequisite to construction of the forespore membrane in wild type, was incomplete. Consequently, formation of the forespore membrane was severely impaired. These observations show that perturbation of Ca2+ homeostasis by mutation of cta4/sev4 blocks sporulation mainly by interfering with forespore membrane assembly.

The Schizosaccharomyces pombe cdt2(+) gene, a target of G1-S phase-specific transcription factor complex DSC1, is required for mitotic and premeiotic DNA replication.

We have defined five sev genes by genetic analysis of Schizosaccharomyces pombe mutants, which are defective in both proliferation and sporulation. sev1(+)/cdt2(+) was transcribed during the G1-S phase of the mitotic cell cycle, as well as during the premeiotic S phase. The mitotic expression of cdt2(+) was regulated by the MCB-DSC1 system. A mutant of a component of DSC1 affected cdt2(+) expression in vivo, and a cdt2(+) promoter fragment containing MCB motifs bound DSC1 in vitro. Cdt2 protein also accumulated in S phase and localized to the nucleus. cdt2 null mutants grew slowly at 30 degrees and were unable to grow at 19 degrees. These cdt2 mutants were also medially sensitive to hydroxyurea, camptothecin, and 4-nitroquinoline-1-oxide and were synthetically lethal in combination with DNA replication checkpoint mutations. Flow cytometry analysis and pulsed-field gel electrophoresis revealed that S-phase progression was severely retarded in cdt2 mutants, especially at low temperatures. Under sporulation conditions, premeiotic DNA replication was impaired with meiosis I blocked. Furthermore, overexpression of suc22(+), a ribonucleotide reductase gene, fully complemented the sporulation defect of cdt2 mutants and alleviated their growth defect at 19 degrees. These observations suggest that cdt2(+) plays an important role in DNA replication in both the mitotic and the meiotic life cycles of fission yeast.

Expression and radiation-induced phosphorylation of histone H2AX in mammalian cells.

The mouse histone H2AX (H2AX) has unique C-terminal Ser residues, which are phosphorylated in response to DNA double-strand breaks (DSBs) by ionizing radiation, suggesting that it plays a role in the maintenance of genomic stability. Here, we show that the H2AX protein was detected in most cells in various tissues, and was abundant in the S phase of the cell cycle. Following X-ray irradiation, H2AX was phosphorylated (gamma-H2AX) in the thymus, small intestine and testis. However, H2AX in epithelial cells in the villi of the small intestine were not strongly phosphorylated, even after X-irradiation. Thus, H2AX was expressed in almost all cells. However, the cells that expressed H2AX were not always phosphorylated by X-irradiation, suggesting a different mechanism of kination in those cells.