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1.
Z. Kato Seiji Fukuda Shunji Tomatsu Hugo Vega Teruo Yasunaga Atsushi Yamagishi Naoto Yamada A. Valencia Luis Alejandro Barrera Kazuko Sukegawa Tadao Orii Naomi Kondo 《Human genetics》1997,101(1):97-101
Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive lysosomal storage disorder caused by a genetic defect in N-acetylgalactosamine-6-sulfate
sulfatase (GALNS). In previous studies, we have found two common mutations in Caucasians and Japanese, respectively. To characterize
the mutational spectrum in various ethnic groups, mutations in the GALNS gene in Colombian MPS IVA patients were investigated,
and genetic backgrounds were extensively analyzed to identify racial origin, based on mitochondrial DNA (mtDNA) lineages.
Three novel missense mutations never identified previously in other populations and found in 16 out of 19 Colombian MPS IVA
unrelated alleles account for 84.2% of the alleles in this study. The G301C and S162F mutations account for 68.4% and 10.5%
of mutations, respectively, whereas the remaining F69V is limited to a single allele. The skewed prevalence of G301C in only
Colombian patients and haplotype analysis by restriction fragment length polymorphisms in the GALNS gene suggest that G301C
originated from a common ancestor. Investigation of the genetic background by means of mtDNA lineages indicate that all our
patients are probably of native American descent.
Received: 2 January 1997 / Accepted: 10 June 1997 相似文献
2.
Y Orii T Sakamoto Y Fukumori T Yamanaka 《Biochemical and biophysical research communications》1992,182(3):1264-1269
The oxygen reaction of Nitrosomonas europaea cytochrome c oxidase containing either 2Cu or 1Cu per two heme a molecules was investigated by the flow-flash technique at 20 degrees C. The reaction profiles of the bacterial enzyme were essentially the same as those of bovine heart cytochrome c oxidase, although the rate of the primary oxygen compound formation was much slower. The 1Cu enzyme exhibited higher rates for both primary oxygen compound formation and intramolecular electron transfer than the 2Cu enzyme. This result clearly indicates that CuA is not essential functionally for the oxidation of ferrous heme a moieties, and suggests its structural importance in maintaining the molecular integrity of N. europaea cytochrome oxidase. 相似文献
3.
Kei Watanabe Kenta Wada Tomoko Ohashi Saki Okubo Kensuke Takekuma Ryoichi Hashizume Jun-Ichi Hayashi Tadao Serikawa Takashi Kuramoto Yoshiaki Kikkawa 《PloS one》2012,7(11)
We discovered a new cataract mutation, kfrs4, in the Kyoto Fancy Rat Stock (KFRS) background. Within 1 month of birth, all kfrs4/kfrs4 homozygotes developed cataracts, with severe opacity in the nuclei of the lens. In contrast, no opacity was observed in the kfrs4/+ heterozygotes. We continued to observe these rats until they reached 1 year of age and found that cataractogenesis did not occur in kfrs4/+ rats. To define the histological defects in the lenses of kfrs4 rats, sections of the eyes of these rats were prepared. Although the lenses of kfrs4/kfrs4 homozygotes showed severely disorganised fibres and vacuolation, the lenses of kfrs4/+ heterozygotes appeared normal and similar to those of wild-type rats. We used positional cloning to identify the kfrs4 mutation. The mutation was mapped to an approximately 9.7-Mb region on chromosome 7, which contains the Mip gene. This gene is responsible for a dominant form of cataract in humans and mice. Sequence analysis of the mutant-derived Mip gene identified a 5-bp insertion. This insertion is predicted to inactivate the MIP protein, as it produces a frameshift that results in the synthesis of 6 novel amino acid residues and a truncated protein that lacks 136 amino acids in the C-terminal region, and no MIP immunoreactivity was observed in the lens fibre cells of kfrs4/kfrs4 homozygous rats using an antibody that recognises the C- and N-terminus of MIP. In addition, the kfrs4/+ heterozygotes showed reduced expression of Mip mRNA and MIP protein and the kfrs4/kfrs4 homozygotes showed no expression in the lens. These results indicate that the kfrs4 mutation conveys a loss-of-function, which leads to functional inactivation though the degradation of Mip mRNA by an mRNA decay mechanism. Therefore, the kfrs4 rat represents the first characterised rat model with a recessive mutation in the Mip gene. 相似文献
4.
Hiroyoshi Fujita Yutaka Orii Seiyo Sano 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,678(1):39-50
δ-Aminolevulinic acid dehydratase (porphobilinogen synthase; 5-aminolevulinate hydro-lyase, EC 4.2.1.24) was purified from rat and rabbit erythrocytes to a homogeneous state. Specific activities were 26.0 and 26.6 units/mg protein for the rat and rabbit enzymes, respectively, and their estimated molecular weight was 280 000, each consisting of 8 subunits of Mr 35 000. In order to quantitate rat δ-aminolevulinic acid dehydratase at several stages of lead-poisoning, a radioimmunoassay technique using goat antiserum against the rat enzyme was developed for the first time. This technique was specific, reproducible and high sensitive allowing determination of 1 ng enzyme. When drinking water containing 25 mM lead acetate was given daily to rats ad lib. the δ-aminolevulinic acid dehydratase activity in the blood, assayed without any pretreatment, decreased to 8% of the control level on the next day. On the contrary, the restored enzyme activity, assayed in the presence of Zn2+ and dithiothreitol, was greater than normal by the fourth day of lead administration in bone-marrow cells and by the ninth day in the peripheral blood. The increased activity level stayed the same from the ninth day onward. The enzyme content as determined directly by the radioimmunoassay technique at this stage was about 2-fold above that the control. There was no significant difference in the number of reticulocytes and the distribution profile of different types of reticulocytes between the lead-exposed and non-exposed rats. Therefore, the increase in the amount of δ-aminolevulinic acid dehydratase in erythrocytes of lead-poisoned rats was suggested to be due to an increased rate of synthesis in the bone-marrow cells. 相似文献
5.
Tadao Matsusaka 《Experimental cell research》1977,110(2):459-462
A method for the induction of synchronous encystment in a hypotrichous ciliate,Histriculus sp. is described. When the ciliates were transferred into 10× Osterhout's solution at around 7 h after disappearance of the food organisms, Tetrahymena, and were maintained at 20 °C, the organisms underwent synchronous encystment. Phase 1 cells (precystic cells) appeared at around 2 h after transfer into the 10× Osterhout solution, and almost all organisms had transformed into phase 1 cells approx. 3 h after transfer. The first cyst appeared at around 3 h after transfer into the 10× solution and essentially 100% of the organisms had transformed into cysts within approx. 4.5 h after transfer. 相似文献
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10.
Tadao Kunihiro Bart Veuger Diana Vasquez-Cardenas Lara Pozzato Marie Le Guitton Kazuyoshi Moriya Michinobu Kuwae Koji Omori Henricus T. S. Boschker Dick van Oevelen 《PloS one》2014,9(4)
Phospholipid-derived fatty acids (PLFA) and respiratory quinones (RQ) are microbial compounds that have been utilized as biomarkers to quantify bacterial biomass and to characterize microbial community structure in sediments, waters, and soils. While PLFAs have been widely used as quantitative bacterial biomarkers in marine sediments, applications of quinone analysis in marine sediments are very limited. In this study, we investigated the relation between both groups of bacterial biomarkers in a broad range of marine sediments from the intertidal zone to the deep sea. We found a good log-log correlation between concentrations of bacterial PLFA and RQ over several orders of magnitude. This relationship is probably due to metabolic variation in quinone concentrations in bacterial cells in different environments, whereas PLFA concentrations are relatively stable under different conditions. We also found a good agreement in the community structure classifications based on the bacterial PLFAs and RQs. These results strengthen the application of both compounds as quantitative bacterial biomarkers. Moreover, the bacterial PLFA- and RQ profiles revealed a comparable dissimilarity pattern of the sampled sediments, but with a higher level of dissimilarity for the RQs. This means that the quinone method has a higher resolution for resolving differences in bacterial community composition. Combining PLFA and quinone analysis as a complementary method is a good strategy to yield higher resolving power in bacterial community structure. 相似文献