Dysbindin-1, a Schizophrenia-Related Protein,Functionally Interacts with the DNA- Dependent Protein Kinase Complex in an Isoform-Dependent Manner

DTNBP1 has been recognized as a schizophrenia susceptible gene, and its protein product, dysbindin-1, is down-regulated in the brains of schizophrenic patients. However, little is known about the physiological role of dysbindin-1 in the central nervous system. We hypothesized that disruption of dysbindin-1 with unidentified proteins could contribute to pathogenesis and the symptoms of schizophrenia. GST pull-down from human neuroblastoma lysates showed an association of dysbindin-1 with the DNA-dependent protein kinase (DNA-PK) complex. The DNA-PK complex interacts only with splice isoforms A and B, but not with C. We found that isoforms A and B localized in nucleus, where the kinase complex exist, whereas the isoform C was found exclusively in cytosol. Furthermore, results of phosphorylation assay suggest that the DNA-PK complex phosphorylated dysbindin-1 isoforms A and B in cells. These observations suggest that DNA-PK regulates the dysbindin-1 isoforms A and B by phosphorylation in nucleus. Isoform C does not contain exons from 1 to 6. Since schizophrenia-related single nucleotide polymorphisms (SNPs) occur in these introns between exon 1 and exon 6, we suggest that these SNPs might affect splicing of DTNBP1, which leads to impairment of the functional interaction between dysbindin-1 and DNA-PK in schizophrenic patients.     

Mapping of Calf Death in Japanese Black Cattle

Weak calf syndrome (WCS) is a major cause of calf death in Japanese Black cattle. Among IARS disorders, the isoleucyl-tRNA synthetase c.235G>C mutation has been identified as one of the causes of WCS. However, calf deaths differing from those attributed to IARS disorder has been occurring. To identify other genes potentially responsible for these calf deaths, we constructed three populations of three bulls (Bull-1, -2 and -3) that did not carry the IARS mutation, and dead calves (18, 28, and 31 calves) and healthy cattle (18, 15, and 10 cattle) sired by these bulls. The populations were genotyped using the BovineSNP50 BeadChip, but homozygosity mapping did not detect any associated genomic regions with calf death. Linkage analysis performed using each population as a paternal half-sib family of Bull-1, Bull-2, and Bull-3 revealed that, in the Bull-1 population, calf death was mapped to the 8.94?Mb–14.53?Mb and 29.82?Mb–33.77?Mb regions of BTA29. The findings suggested that the incidence of calf death in calves sired by Bull-1 was a hereditary disease exhibiting a dominant, not recessive, inheritance pattern.     

Adsorption of mutagens by refined corn bran

Refined corn bran (RCB), a dietary fiber derived from the mechanical refining of corn hulls, effectively adsorbed various environmental mutagens. When RCB was added at a concentration of 10 mg/ml to an aqueous solution of dinitropyrene (DNP), 91.6% of the mutagenicity towards Salmonella tester strain TA98 disappeared. Under similar conditions decreases in mutagenicity of DNP using wheat bran and cellulose powder were 58.4% and 43.0%, respectively. The adsorption of DNP to the fibers appeared irreversible since little mutagenicity was recovered by washing the treated fibers with aqueous buffer solutions of various pHs. Even with an organic solvent (methanol: ammonium hydroxide 50:1), only 2/3 of the mutagenicity of DNP was recovered. RCB could similarly adsorb mutagenic heterocyclic amines such as IQ, Trp-P-1, Trp-P-2, Glu-P-1, and Glu-P-2.     

The Structure of Detoxin D1

The structure of detoxin D₁, one of the main active principles of detoxio complex, has been established on the basis of the degradative studies and spectral evidences as depicted in formula (I).

Detoxin D₁ has been demonstrated to belong to a new class of the depsipeptide contained an amino acid designated detoxinine which was newly isolated as a natural product.     

Seasonally different modes of seed dispersal in the prostrate annual, <Emphasis Type="Italic">Chamaesyce maculata</Emphasis> (L.) Small (Euphorbiaceae), with multiple overlapping generations

The modes of seed dispersal in the prostrate annual, Chamaesyce maculata, with multiple overlapping generations were investigated. We found that C. maculata has two modes of seed dispersal; autochory in the summer and myrmecochory in the autumn. Seasonally different modes of seed dispersal have not been known in other plant species. The large proportion of seeds produced in the summer was positioned further than the expanse of the parent plants by automatic mechanical seed dispersal. Therefore, autochory would be effective for avoiding competition between parent and offspring plants. No autochory occurred in the seeds produced in the autumn. The seeds of C. maculata without an elaiosome were dispersed by seed-collecting ants in the autumn. Although 18 ant species in total visited the plants of C. maculata at the 50 sites investigated, only two ant species, Tetramorium tsushimae and Pheidole noda frequently carried the seeds of C. maculata. The low frequency of seeds carried out of the nest by P. noda suggests that the workers of P. noda carry the seeds as food into their nest. So, P. noda might be a less effective seed disperser for C. maculata, corresponding to the effectiveness of seed dispersal by harvester ants. However, T. tsushimae ants frequently carried the seeds into and out of their nest, suggesting that T. tsushimae do not regard the seeds of C. maculata as a food resource. Thus, T. tsushimae may be an effective seed disperser for C. maculata.     

Direct Comparisons of 2D and 3D Dental Microwear Proxies in Extant Herbivorous and Carnivorous Mammals

The analysis of dental microwear is commonly used by paleontologists and anthropologists to clarify the diets of extinct species, including herbivorous and carnivorous mammals. Currently, there are numerous methods employed to quantify dental microwear, varying in the types of microscopes used, magnifications, and the characterization of wear in both two dimensions and three dimensions. Results from dental microwear studies utilizing different methods are not directly comparable and human quantification of wear features (e.g., pits and scratches) introduces interobserver error, with higher error being produced by less experienced individuals. Dental microwear texture analysis (DMTA), which analyzes microwear features in three dimensions, alleviates some of the problems surrounding two-dimensional microwear methods by reducing observer bias. Here, we assess the accuracy and comparability within and between 2D and 3D dental microwear analyses in herbivorous and carnivorous mammals at the same magnification. Specifically, we compare observer-generated 2D microwear data from photosimulations of the identical scanned areas of DMTA in extant African bovids and carnivorans using a scanning white light confocal microscope at 100x magnification. Using this magnification, dental microwear features quantified in 2D were able to separate grazing and frugivorous bovids using scratch frequency; however, DMTA variables were better able to discriminate between disparate dietary niches in both carnivorous and herbivorous mammals. Further, results demonstrate significant interobserver differences in 2D microwear data, with the microwear index remaining the least variable between experienced observers, consistent with prior research. Overall, our results highlight the importance of reducing observer error and analyzing dental microwear in three dimensions in order to consistently interpret diets accurately.     

Separation of mammalian cell surface proteins by a two-dimensional gel electrophoresis system

Separation of externally exposed plasma membrane proteins of mammalian cells has been achieved by a new two-dimensional gel electrophoresis system. The proteins were separated in the first dimension on cylindrical polyacrylamide gels containing 0.1% sodium dodecyl sulfate (SDS) and in the second dimension on polyacrylamide slab gels containing 9 M urea, 0.1% SDS, and 0.1% Triton CF10. Using this method we have obtained reproducible high-resolution patterns of cell surface proteins of differentiated rat neuro-tumor cells in culture and of normal rat retinal cells. Different cell types show characteristic cell surface proteins in addition to ubiquitous ones. The number of common surface proteins between two cell types account for approximately half of the total surface proteins. By immunoprecipitation we have also found that rabbit anti-serum against a rat neuronal cell line can recognize most of these external proteins. Since the separation in the first dimension is done in the presence of SDS and the second dimension in the presence of SDS, a non-ionic detergent, and urea, the technique is particularly suitable for proteins that are of poor solubility. In addition to size, net charge and hydrophobicity appear to be important factors in the separation. Virtually all of the proteins that run in the first dimension can be recovered and further separated in the second.     

MTRAP: Pairwise sequence alignment algorithm by a new measure based on transition probability between two consecutive pairs of residues

Background  

Sequence alignment is one of the most important techniques to analyze biological systems. It is also true that the alignment is not complete and we have to develop it to look for more accurate method. In particular, an alignment for homologous sequences with low sequence similarity is not in satisfactory level. Usual methods for aligning protein sequences in recent years use a measure empirically determined. As an example, a measure is usually defined by a combination of two quantities (1) and (2) below: (1) the sum of substitutions between two residue segments, (2) the sum of gap penalties in insertion/deletion region. Such a measure is determined on the assumption that there is no an intersite correlation on the sequences. In this paper, we improve the alignment by taking the correlation of consecutive residues.