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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
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Changes in Targeting Efficiencies of Proteins to Plant Microbodies Caused by Amino Acid Substitutions in the Carboxy-terminal Tripeptide 总被引:7,自引:0,他引:7
Hayashi Makoto; Aoki Masahiro; Kondo Maki; Nishimura Mikio 《Plant & cell physiology》1997,38(6):759-768
It has been demonstrated that the carboxyl terminus of microbodyenzymes functions as a targeting signal to microbodies in higherplants. We have examined an ability of 24 carboxy-terminal aminoacid sequences to facilitate the transport of a cytosolic passengerprotein, ß-glucuroni-dase, into microbodies in greencotyledonary cells of trans-genic Arabidopsis. Immunoelectronmicroscopic analysis revealed that carboxy-terminal tripeptidesequences of the form [C/A/S/P]-[K/R]-[I/L/M] function as amicrobody-targeting signal, although tripeptides with prolineat the first amino acid position and isoleucine at the carboxylterminus show weak targeting efficiencies. All known micro-bodyenzymes that are synthesized in a form similar in size to themature molecule, except catalase, contain one of these tripeptidesequences at their carboxyl terminus. (Received April 14, 1997; Accepted April 8, 1997) 相似文献
5.
Michinari Hamaguchi Koichiro Maeno Yoshiyuki Nagai Masao Iinuma Tetsuya Yoshida Toshisada Matsumoto 《Microbiology and immunology》1980,24(1):51-63
When p-fluorophenylalanine (FPA) was added to influenza virus RI/5+-infected cells 4 hr after infection, virus-specific proteins were synthesized but infectious progeny virus was not produced. In these cells, synthesis of viral RNA was strongly inhibited and nucleoprotein (NP) antigen was found predominantly in the nucleus in contrast to untreated cells in which NP antigen was distributed throughout the whole cell. The intracellular location and migration of NP were examined by isotope labeling followed by fractionation of infected cells. In untreated cells, a large portion of the NP was present in the cytoplasm and most of it was detected in the form of ribonucleoprotein (RNP). In contrast, in FPA-treated cells little viral RNP was detectable and NP was present predominantly in the nucleus in a nonassembled, soluble form. When FPA was removed from the culture, synthesis of viral RNA was soon restored and a large amount of viral RNP appeared in the cytoplasm; this was followed by the production of infectious virus. The results of the experiments suggest that the NP synthesized in the presence of FPA is not assembled into viral RNP because of the lack of available RNA, and such NP migrates readily into the nucleus and accumulates there. 相似文献
6.
Summary Tracheobronchial epithelium, thyroid organ, thymus, of the developing rats were examined by immunohistochemistry using anti-spot 35 calbindin-antiserum. At E 14, weak to moderate immunoreactivity for spot 35-calbindin was detected in the airway epithelia of the distal half of the trachea and the extrapulmonary bronchus. The immunoreactive cells increased in intensity at E 16–E 21, but decreased markedly after birth. These cells were non-ciliated cells and comprised a majority of the epithelial cells especially in the ventral/cartilaginous portion of the airway. They were characterized by microvilli, vacuoles, granular and agranular endoplasmic reticulum. Typical ciliated cells, which were much less numerous than the immunopositive non-ciliated cells, were immunonegative. In thyroid gland, calbindin-immunoreactive cells first appeared at E 18. They increased in number at E 20-P 1 and decreased gradually after P 7. These cells were the parafollicular cells characterized by numerous secretory granules and situated in close proximity to the basal surface of the follicular cells. In the thymus, immunoreactive cells appeared in the thymic medulla at E 20. They increased in number at P 1, but decreased gradually after P 7. They were stellate in shape and had vesicles, vacuoles, intermediate filaments and represented a subpopulation of thymic reticular epithelial cells. Such a transient appearance of spot 35-calbindin in these cells suggests that this protein may be involved in the regulation of differentiation or may be involved in the process of secretion during the limited developmental period. 相似文献
7.
S Tsuzuki T Fushiki A Kondo H Murayama E Sugimoto 《European journal of biochemistry》1991,199(1):245-252
The adaptation to a high protein diet of the concentration and mRNA level of a trypsin-sensitive, cholecystokinin-releasing peptide (monitor peptide), which was proposed to be the mediator of the cholecystokinin release in response to protein intake, was investigated in the rat pancreas. Adult rats were placed on one of two isocaloric diets. One group was fed a 22% casein diet (control diet) and the other a 64% casein diet (high-protein diet) for 14 days. In order to quantify the monitor peptide separately from pancreatic secretory trypsin inhibitor (PSTI-II), which is highly similar in its amino acid and mRNA nucleotide sequences to the monitor peptide but has less cholecystokinin-releasing activity, we used specific assay methods: HPLC was used for determining the monitor peptide concentration in zymogen granules and a synthetic oligonucleotide probe for determining the mRNA of the monitor peptide in the pancreas. The concentrations in the zymogen granules and the mRNA levels in the pancreas of the two peptides increased in parallel during the adaptation to the high protein diet, indicating that these two peptides were under the same control during the adaptation. The concentration and mRNA level of the monitor peptide, which were measured after 0, 3, and 14 days, increased throughout the experiment period, as did the concentration of trypsin. This suggested that the monitor peptide and trypsin may respond to similar signals during the adaptation to a high protein diet and that this apparent coordination may facilitate the adaptation of the pancreas to the diet. 相似文献
8.
Tetsuya Akamatsu 《Developmental biology》2009,325(2):434-443
The submandibular gland (SMG) develops through the epithelial-mesenchymal interaction mediated by many growth/differentiation factors including activin and BMPs, which are synthesized as inactive precursors and activated by subtilisin-like proprotein convertases (SPC) following cleavage at their R-X-K/R-R site. Here, we found that Dec-RVKR-CMK, a potent inhibitor of SPC, inhibited the branching morphogenesis of the rat embryonic SMG, and caused low expression of a water channel AQP5, in an organ culture system. Dec-RVKR-CMK also decreased the expression of PACE4, a SPC member, but not furin, another SPC member, suggesting the involvement of PACE4 in the SMG development. Heparin, which is known to translocate PACE4 in the extracellular matrix into the medium, and an antibody specific for the catalytic domain of PACE4, both reduced the branching morphogenesis and AQP5 expression in the SMG. The inhibitory effects of Dec-RVKR-CMK were partially rescued by the addition of recombinant BMP2, whose precursor is one of the candidate substrates for PACE4 in vivo. Further, the suppression of PACE4 expression by siRNAs resulted in decreased expression of AQP5 and inhibition of the branching morphogenesis in the present organ culture system. These observations suggest that PACE4 regulates the SMG development via the activation of some growth/differentiation factors. 相似文献
9.
Tanaka Kiyoshi; Mitsuhashi Hiromi; Kondo Noriaki; Sugahara Kiyoshi 《Plant & cell physiology》1982,23(8):1467-1470
The substrate level of the photosynthetic reductive pentosephosphate cycle in spinach leaves during SO2 fumigation wassurveyed. At the beginning of SO2 fumigation, fructose-1,6-bisphosphateincreased and fructose-6-phosphate decreased, while ribulose-1,5-bisphosphateremained unchanged and 3-phosphoglyceric acid rapidly decreased.These results suggested that the inhibition of photosynthesisin spinach leaves with SO2 might be due to inactivation of fructose-1,6-bisphosphatase. (Received May 26, 1982; Accepted September 27, 1982) 相似文献
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