An approach based on development of a large archive of single-nucleotide polymorphisms (SNPs) throughout the human genome is expected to facilitate large-scale studies to identify genes associated ...with drug efficacy and side effects, or susceptibility to common diseases. We have already described collections of SNPs present among various genes encoding drug-metabolizing enzymes. Here we report SNPs for such enzymes at additional loci, including 8 alcohol dehydrogenases, 12 glutathione S-transferases, and 18 belonging to the NADH-ubiquinone oxidoreductase family. Among DNA samples from 48 Japanese volunteers, we identified a total of 434 SNPs at these 38 loci: 27 within coding elements, 52 in 5' flanking regions, five in 5' untranslated regions, 293 in introns, 20 in 3' untranslated regions, and 37 in 3' flanking regions. The ratio of transitions to transversions was approximately 2.1 to 1. Among the 27 coding SNPs, 13 were nonsynonymous changes that resulted in amino acid substitutions. Our collection of SNPs derived from this study should prove useful for investigations designed to detect associations between genetic variations and common diseases or responsiveness to drug therapy.
The
Notch3 gene, a member of the
Notch gene family, is expressed in a wide variety of tissues during development. We generated and analyzed
Notch3-deficient mice to assess the in vivo role of the
...Notch3 gene. Consistent with previous observation of Krebs et al. Characterization of Notch3-deficient mice: normal embryonic development and absence of genetic interactions with a Notch1 mutation, Genesis 37 (3) (2003) 139–143, the
Notch3
−/− mice were viable, fertile, and developed normally despite abundant expression of
Notch3 in various embryonic tissues. We examined the details of
Notch1,
2, and
4 expressions in the
Notch3
−/− embryos compared with those in wild-type embryos. As a result, we found that a deficiency in
Notch3 did not affect the expression of
Notch1,
2, and
4, and that either
Notch1 or
Notch2, or sometimes both, was always expressed in all
Notch3-expressing tissues examined. These results support the idea that other
Notch genes functionally compensate for
Notch3 during embryonic development. We also surveyed the adult tissues of
Notch3
−/− mice and found significantly fewer thymocytes in 10-week-old mice. Therefore, the thymus might be a target tissue affected by
Notch3 deficiency.
A total of 65 cases of Creutzfeldt–Jakob disease with a history of cadaveric dura
transplantation in Japan were analysed to clarify the epidemiologic features of such patients
and to explore whether ...other such patients will appear in the future. The age at
transplantation averaged 44·4 years with a standard deviation of 14·4 years. The age at onset
had an average of 53·0 years with a standard deviation of 14·1 years. The shortest latent period
was 14 months, and the longest was 218 months with an average of 103·1 months and a
standard deviation of 49·9 months. From the relationship between the calendar year at
transplantation and the latent period, other such patients will appear in the near future. The
current data suggested that several patients with Creutzfeldt–Jakob disease will occur from
those receiving cadaveric dura mater grafts in the near future.
We immunohistochemically examined tissue sections from patients with prion protein (PrP) polymorphism using hydrolytic autoclaving enhancement. Abnormal PrP accumulations could be classified into ...plaque formations (plaque-type) and the diffuse gray matter stainings including synaptic structures (synaptic-type). Insertional polymorphism, a point mutation in codon 102 or 117/129, and a polymorphism in codon 129 (Val129) result in plaque-type PrP accumulations. The patients with codon 102 mutation also have synaptic-type PrP accumulations. However, a point mutation in codon 200 did not show plaque-type accumulations, and only showed synaptic-type PrP accumulations. Likewise, sporadic Creutzfeldt-Jakob disease patients without any known mutations only have synaptic type accumulations. These results imply that the primary structures of PrP influence the phenotype of prion diseases, especially in abnormal PrP distributions of the central nervous system.
To optimize the strategies for population-based pharmacogenetic studies, we extensively analyzed single-nucleotide polymorphisms (SNPs) and haplotypes in 199 drug-related genes, through use of 4,190 ...SNPs in 752 control subjects. Drug-related genes, like other genes, have a haplotype-block structure, and a few haplotype-tagging SNPs (htSNPs) could represent most of the major haplotypes constructed with common SNPs in a block. Because our data included 860 uncommon (frequency <0.1) SNPs with frequencies that were accurately estimated, we analyzed the relationship between haplotypes and uncommon SNPs within the blocks (549 SNPs). We inferred haplotype frequencies through use of the data from all htSNPs and one of the uncommon SNPs within a block and calculated four joint probabilities for the haplotypes. We show that, irrespective of the minor-allele frequency of an uncommon SNP, the majority (mean ± SD frequency 0.943±0.117) of the minor alleles were assigned to a single haplotype tagged by htSNPs if the uncommon SNP was within the block. These results support the hypothesis that recombinations occur only infrequently within blocks. The proportion of a single haplotype tagged by htSNPs to which the minor alleles of an uncommon SNP were assigned was positively correlated with the minor-allele frequency when the frequency was <0.03 (
P<.000001;
n=233 Spearman’s rank correlation coefficient). The results of simulation studies suggested that haplotype analysis using htSNPs may be useful in the detection of uncommon SNPs associated with phenotypes if the frequencies of the SNPs are higher in affected than in control populations, the SNPs are within the blocks, and the frequencies of the SNPs are >0.03.
We analyzed neuropathologic features of 23 Japanese patients with sporadic Creutzfeldt-Jakob disease (sCJD) by means of prion protein (PrP) immunolabeling associated with codon 129 polymorphism of ...the PrP gene and western blot analysis of protease-resistant PrP (PrP type). Clinical features, particularly age at onset, disease duration, periodic synchronous discharge and presence of myoclonus, were also analyzed. This study included 11 cases of subacute spongiform encephalopathy (SSE), 10 cases of panencephalopathic (PE)-type sCJD and two cases of thalamic-type sCJD, classified according to cerebral pathology findings. According to PrP gene polymorphism and PrP type, 18 cases were classified as MM1-type, two as MV1-type, two as MM2-type and one as MM1 + 2-type sCJD. SSE and PE-type sCJD showed similar clinical features, with the exception of disease duration, codon 129 polymorphism and PrP type. Thalamic-type sCJD showed different clinical features and PrP type. We suggest that SSE and PE-type sCJD comprise the sCJD subtype and that PE-type sCJD is a prolonged pathologic phenotype of SSE. When we compare our results with those from a series of Caucasian sCJD patients, the percentages of codon 129 polymorphisms differed, as did classification based on PrP gene polymorphism and PrP type; our series included many PE-type sCJD cases and disease duration was relatively long and MM2-type cases showed clinicopathologic variability.
The authors examined 10 patients with Gerstmann-Sträussler syndrome or Creutzfeldt-Jakob disease and 10 with Alzheimer's disease (AD). Immunohistochemistry using anti-prion protein (PrP) and ...anti-beta/A4 protein (beta/A4) coupled with formic acid pretreatment could detect Congophilic and non-Congophilic deposits. Prion protein deposits were classified into five types and compared with types of beta/A4 deposits. Kuru plaques with multicentric cores and fine granular deposits were a characteristic feature of PrP deposits. Some types of PrP or beta/A4 deposits depend on the anatomic sites. To clarify the relationship of microglia and astrocytes to PrP or beta/A4 deposits, double-immunostaining method was performed. In both kuru and senile plaques, microglia were closely linked to the Congophilic plaques. Astrocytes, however, extended their processes toward the plaques even in the non-Congophilic plaques. These observations strongly suggest that similar glial association with plaque formation may be involved in both kuru and senile plaques, although the amyloid core proteins differ.
Background: Courtship is the best-studied behavior in Drosophila melanogaster, and work on its anatomical basis has concentrated mainly on the functional identification of sexually dimorphic sites in ...the brain. Much less is known of the more expansive, nondimorphic, but nonetheless essential, neural elements subserving male courtship behavior.
Results: Sites in the CNS mediating initiation and early steps of male courtship in Drosophila melanogaster were identified by analyzing the behavior of mosaic flies expressing transgenes designed either to suppress neurotransmission or enhance neuronal excitability. Suppression of neurotransmission was accomplished by means of the dominantly acting, temperature-sensitive dynamin mutation shibirets1, whereas enhanced neuronal excitability was produced by means of a novel, dominantly acting, truncated eag potassium channel. By using a new, landmark-based procedure for aligning diverse expression patterns among the various mosaic strains, a comparison of courtship performance and affected brain sites in strains expressing the transgenes identified a cluster of cells in the posterior lateral protocerebrum that exerts reciprocal effects on the initiation of courtship, suppressing it when they are inactivated and enhancing it when they are hyperactivated, indicative of cells that normally play an excitatory, triggering role. A separate group of nearby cells, slightly more anterior in the lateral protocerebrum, was found to inhibit courtship when its activity is enhanced, indicative of an inhibitory role in courtship.
Conclusions: A cluster of cells, some excitatory and some inhibitory, in the lateral protocerebrum regulates courtship initiation in Drosophila. These cells are likely to be an integration center for the multiple sensory inputs that trigger male courtship.
Here we show that prolyl isomerase Pin1 is involved in the Aβ production central to the pathogenesis of Alzheimer’s disease. Enzyme immunoassay of brains of the
Pin1-deficient mice revealed that ...production of Aβ40 and Aβ42 was lower than that of the wild-type mice, indicating that Pin1 promotes Aβ production in the brain. GST-Pin1 pull-down and immunoprecipitation assay revealed that Pin1 binds phosphorylated Thr668-Pro of C99. In the
Pin1
−/− MEF transfected with
C99,
Pin1 co-transfection enhanced the levels of Aβ40 and Aβ42 compared to that without
Pin1 co-transfection. In COS7 cells transfected with
C99,
Pin1 co-transfection enhanced the generation of Aβ40 and Aβ42, and reduced the expression level of C99, facilitating the C99 turnover. Thus, Pin1 interacts with C99 and promotes its γ-cleavage, generating Aβ40 and Aβ42. Further, GSK3 inhibitor lithium blocked Pin1 binding to C99 by decreasing Thr668 phosphorylation and attenuated Aβ generation, explaining the inhibitory effect of lithium on Aβ generation.
We immunohistochemically studied the location of abnormal prion protein in the central nervous system and visceral organs at the clinical and preclinical stages of mice infected with ...Creutzfeldt-Jakob disease via intraperitoneal route. Abnormal prion protein was diffusely distributed in the central nervous system. The sequential study showed that its stainings were first detected 120 days after inoculation, were found in all mice after 180 days, and were the most intense and widespread after 270 days. There was no restricted involvement at the early stages nor rostrally dominant distribution of the stainings that had been found in mice infected via intracerebral route. Abnormal prion protein was also located in the follicular dendritic cells in the spleen, lymph nodes, intestinal Peyer's patch, and thymus. Its stainings were first detected in the spleen, lymph nodes, and Peyer's patch 14 or 30 days after inoculation. In the thymus, however, the stainings were first detected after 210 days in the germinal centers formed in the medulla.
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