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Y Mukai

Publications and source records attributed to Y Mukai.

At least 37 records · Page 2Linked to original sources
PubMed2001

Comparison of starch-branching enzyme genes reveals evolutionary relationships among isoforms. Characterization of a gene for starch-branching enzyme IIa from the wheat genome donor Aegilops tauschii.

Genes and cDNAs for starch-branching enzyme II (SBEII) have been isolated from libraries constructed from Aegilops tauschii and wheat (Triticum aestivum) endosperm, respectively. One class of genes has been termed wSBEII-DA1 and encodes the N terminus reported for an SBEII from wheat endosperm. On the basis of phylogenetic comparisons with other branching enzyme sequences, wSBEII-DA1 is considered to be a member of the SBEIIa class. The wSBEII-DA1 gene consists of 22 exons with exons 4 to 21 being identical in length to the maize (Zea mays) SBEIIb gene, and the gene is located in the proximal region of the long arm of chromosome 2 at a locus designated sbe2a. RNA encoding SBEIIa can be detected in the endosperm from 6 d after flowering and is at its maximum level from 15 to 18 d after anthesis. Use of antibodies specific for SBEIIa demonstrated that this protein was present in both the soluble and granule bound fractions in developing wheat endosperm. We also report a cDNA sequence for SBEIIa that could arise by variant transcription/splicing. A second gene, termed wSBEII-DB1, was isolated and encodes an SBEII, which shows greater sequence identity with SBEIIb-type sequences than with SBEIIa-type sequences. Comparisons of SBEII gene structures among wheat, maize, and Arabidopsis indicate the lineage of the SBEII genes.

1,4-alpha-Glucan Branching Enzyme↗
PubMed2001

Total occlusion of inferior vena cava in a patient with antiphospholipid antibody syndrome associated with behçet's disease.

Behçet's disease frequently involves the venous system, usually affecting small vessels, but sometimes large vessels such as the vena cava. Antiphospholipid antibody syndrome is associated with an increased incidence of arterial and venous thrombosis. A 29-year-old male with Behçet's disease developed bilateral leg edema secondary to thrombotic occlusion of the inferior vena cava. Laboratory tests revealed positive antiphospholipid antibodies and lupus anticoagulant. Treatment with steroid and warfarin subsequent to intravenous administration of uro-kinase resulted in improvement of symptoms. The association of antiphospholipid antibody syndrome and Behçet's disease may have caused the total thrombotic occlusion of the vena cava in this case.

Adult↗
PubMed2001

BAC FISH analysis in Allium cepa.

Onion (Allium cepa L.; 1C=15,000 Mb) is an agriculturally important plant. The genome of onion has been extensively studied at the conventional cytogenetic level, but molecular analyses have lagged behind due to its large genome size. To overcome this bottleneck, a partial bacterial artificial chromosome (BAC) library of onion was constructed. The average insert size of the BAC library was about 100 kb. A total of 48,000 clones, corresponding to 0.32 genome equivalent, were obtained. Fluorescent in situ hybridization (FISH) screening resulted in identification of BAC clones localized on centromeric, telomeric, or several limited interstitial chromosomal regions, although most of the clones hybridized with entire chromosomes. The partial BAC library proved to be a useful resource for molecular cytogenetic studies of onion, and should be useful for further mapping and sequencing studies of important genes of this plant. BAC FISH screening is a powerful method for identification of molecular cytogenetic markers in large-genome plants.

Centromere↗
PubMed2001

Identification and chromosomal location of tandemly repeated DNA sequences in Allium cepa.

A 314-bp tandemly repeated DNA sequence, named pAc074, was characterized in Allium cepa by fluorescence in situ hybridization (FISH) analyses using random amplified fragment as probe. The nucleotide sequences of the clone pAc074 is partially homologous to the satellite DNA sequences, ACSAT1, ACSAT2, and ACSAT3, of A. cepa with 81%, 81% and 78% similarity, respectively. Our sequential C-banding and FISH with pAc074 probe also clearly showed a close relation between Cheterochromatin at telomeric region and pAc074 sequences on all the chromosomes except on chromosome 6. On the long arm of chromosome 7, pAc074 sequences appeared as interstitial band which did not correspond to C-heterochromatin bands. Instead, the C-heterochromatin bands corresponded with the 5S rDNA signals. This is the first evidence of simultaneous banding of the 5S rDNA and C-band in A. cepa.

Base Sequence↗
PubMed2000

Ssn6-Tup1 interacts with class I histone deacetylases required for repression.

Ssn6-Tup1 regulates multiple genes in yeast, providing a paradigm for corepressor functions. Tup1 interacts directly with histones H3 and H4, and mutation of these histones synergistically compromises Ssn6-Tup1-mediated repression. In vitro, Tup1 interacts preferentially with underacetylated isoforms of H3 and H4, suggesting that histone acetylation may modulate Tup1 functions in vivo. Here we report that histone hyperacetylation caused by combined mutations in genes encoding the histone deacetylases (HDACs) Rpd3, Hos1, and Hos2 abolishes Ssn6-Tup1 repression. Unlike HDAC mutations that do not affect repression, this combination of mutations causes concomitant hyperacetylation of both H3 and H4. Strikingly, two of these class I HDACs interact physically with Ssn6-Tup1. These findings suggest that Ssn6-Tup1 actively recruits deacetylase activities to deacetylate adjacent nucleosomes and promote Tup1-histone interactions.

Acetylation↗
PubMed2000

INE: a rice genome database with an integrated map view.

The Rice Genome Research Program (RGP) launched a large-scale rice genome sequencing in 1998 aimed at decoding all genetic information in rice. A new genome database called INE (INtegrated rice genome Explorer) has been developed in order to integrate all the genomic information that has been accumulated so far and to correlate these data with the genome sequence. A web interface based on Java applet provides a rapid viewing capability in the database. The first operational version of the database has been completed which includes a genetic map, a physical map using YAC (Yeast Artificial Chromosome) clones and PAC (P1-derived Artificial Chromosome) contigs. These maps are displayed graphically so that the positional relationships among the mapped markers on each chromosome can be easily resolved. INE incorporates the sequences and annotations of the PAC contig. A site on low quality information ensures that all submitted sequence data comply with the standard for accuracy. As a repository of rice genome sequence, INE will also serve as a common database of all sequence data obtained by collaborating members of the International Rice Genome Sequencing Project (IRGSP). The database can be accessed at http://www. dna.affrc.go.jp:82/giot/INE. html or its mirror site at http://www.staff.or.jp/giot/INE.html

Chromosomes, Artificial, Yeast↗
PubMed2000

Hydrogen peroxide is an endothelium-derived hyperpolarizing factor in mice.

The endothelium plays an important role in maintaining vascular homeostasis by synthesizing and releasing several endothelium-derived relaxing factors, such as prostacyclin, nitric oxide (NO), and the previously unidentified endothelium-derived hyperpolarizing factor (EDHF). In this study, we examined our hypothesis that hydrogen peroxide (H(2)O(2)) derived from endothelial NO synthase (eNOS) is an EDHF. EDHF-mediated relaxation and hyperpolarization in response to acetylcholine (ACh) were markedly attenuated in small mesenteric arteries from eNOS knockout (eNOS-KO) mice. In the eNOS-KO mice, vasodilating and hyperpolarizing responses of vascular smooth muscle per se were fairly well preserved, as was the increase in intracellular calcium in endothelial cells in response to ACh. Antihypertensive treatment with hydralazine failed to improve the EDHF-mediated relaxation. Catalase, which dismutates H(2)O(2) to form water and oxygen, inhibited EDHF-mediated relaxation and hyperpolarization, but it did not affect endothelium-independent relaxation following treatment with the K(+) channel opener levcromakalim. Exogenous H(2)O(2) elicited similar relaxation and hyperpolarization in endothelium-stripped arteries. Finally, laser confocal microscopic examination with peroxide-sensitive fluorescence dye demonstrated that the endothelium produced H(2)O(2) upon stimulation by ACh and that the H(2)O(2) production was markedly reduced in eNOS-KO mice. These results indicate that H(2)O(2) is an EDHF in mouse small mesenteric arteries and that eNOS is a major source of the reactive oxygen species.

Acetylcholine↗
PubMed2000

Mapping of rDNA on the chromosomes of Eleusine species by fluorescence in situ hybridization.

Mapping of rDNA sites on the chromosomes of four diploid and two tetraploid species of Eleusine has provided valuable information on genome relationship between the species. Presence of 18S-5.8S-26S rDNA on the largest pair of the chromosomes, location of 5S rDNA at four sites on two pairs of chromosomes and presence of 18S-5.8S-26S and 5S rDNA at same location on one pair of chromosomes have clearly differentiated E. multiflora from rest of the species of Eleusine. The two tetraploid species, E. coracana and E. africana have the same number of 18S-5.8S-26S and 5S rDNA sites and located at similar position on the chromosomes. Diploid species, E. indica, E. floccifolia and E. tristachya have the same 18S-5.8S-26S sites and location on the chromosomes which also resembled with the two pairs of 18S-5.8S-26S rDNA locations in tetraploid species, E. coracana and E. africana. The 5S rDNA sites on chromosomes of E. indica and E. floccifolia were also comparable to the 5S rDNA sites of E. africana and E. coracana. The similarity of the rDNA sites and their location on chromosomes in the three diploid and two polyploid species also supports the view that genome donors to tetraploid species may be from these diploid species.

Chromosomes↗
PubMed2000

The development of normal feeding and swallowing: Showa University study of the feeding function.

Since the 1980s the Department of Hygiene and Oral Health at the Showa University School of Dentistry has focused its research efforts on the development of feeding function and disorders. In addition, we have treated dysphagic children and dysphagic elderly using our feeding training program approach. The developmental course of the feeding function includes the following steps: 1) Suckle feeding and prefeeding period; 2) Acquiring the ability to swallow with lips closed; 3) Acquiring the ability to take food with lips closed; 4) Acquiring the ability to push mashed food with the tongue and anterior hard palate; 5) Acquiring the ability to perform mastication; 6) Beginning self-feeding; 7) Beginning finger feeding; 8) Beginning using table ware.

Child Development↗
PubMed2000

Assessment of the development of hand and mouth coordination when taking food into the oral cavity.

The purpose of this study was to establish an assessment method for evaluation of hand and mouth coordination during self-feeding. The subjects were four normally developed infants. Their feeding behavior was videotaped at two or four week intervals (from age eight months to thirty-six months). The items analyzed were nine viewpoints for finger feeding and eight viewpoints for spoon-feeding. The results obtained included: finger feeding--development of cylinder and pinch grasp, two patterns of hand in relation to neck and trunk, placement of food into the mouth, developmental aspects of neck rotation when taking food with the lips; spoon feeding--holding technique, flexion of elbow and shoulder, taking food from the spoon bowl by the lips, patterns of neck rotation. From the results of these observations, we conclude that the items analyzed in this study can be useful for the assessment of the developmental process of hand and mouth coordination in self-feeding.

Child Development↗
PubMed2000

[Synthesis of fluorescent derivatization reagent 2-(4-carboxyphenyl)-naphthoimidazole and its application in the determination of alcohols by high performance liquid chromatography].

A new sensitive pre-column fluorescent derivatization method, which employs high performance liquid chromatography(HPLC) with fluorometric detection, for the determination of alcohols is described. The alcohols were transformed into the corresponding fluorescent esters by treating with 2-(4-carboxyphenyl)-naphthoimidazole in dichloromethane in the presence of 4-piperidinopyridine (PIP) and 1-isopropyl-3-(3-dimethylaminopropyl)-1-carbodiimide perchlorate(IDC) at 80 degrees C for 10 min. The resultant mixture was analyzed by HPLC on a reversed phase column(Zorbax Bp C8, 4.6 mm i.d. x 250 mm, 5 microns) with acetonitrile-methanol (volume ratio was 90:10) as mobile phase, and the sample volume was 20 microL. Monitored excitation and emission wavelengths were 345 nm and 485 nm respectively in determination of the alcohol. The calibration curve of cholesterol is linear between 0 and 2.5 g/L with correlation coefficient of 0.9992. The average recovery was 96.15% with RSD of 1.39%. The lowest detectable mass concentration of cholesterol was 1.0 microgram/L (S/N = 3).

Alcohols↗
PubMed1999

A series of protein phosphatase gene disruptants in Saccharomyces cerevisiae.

Thirty-two protein phosphatase (PPase) genes were identified in the genome nucleotide sequence of Saccharomyces cerevisiae. We constructed S. cerevisiae disruptants for each of the PPase genes and examined their growth under various conditions. The disruptants of six putative PPase genes, i.e. of YBR125c, YCR079w, YIL113w, YJR110w, YNR022c and YOR090c, were created for the first time in this study. The glc7, sit4 and cdc14 disruptants were lethal in our strain background. The remaining 29 PPase gene disruptants were viable at 30 degrees C and 37 degrees C, but only one disruptant, yvh1, showed intrinsic cold-sensitive growth at 13 degrees C. Transcription of the YVH1 gene was induced at 13 degrees C, consistent with an idea that Yvh1p has a specific role for growth at a low temperature. The viable disruptants grew normally on nutrient medium containing sucrose, galactose, maltose or glycerol as carbon sources. The ppz1 disruptant was tolerant to NaCl and LiCl, while the cmp2 disruptant was sensitive to these salts, as reported previously, and none of the other viable PPase disruptants exhibited the salt sensitivity. When the viable disruptants were tested for sensitivity to drugs, i.e. benomyl, caffeine and hydroxyurea, ppz1 and ycr079w disruptants exhibited sensitivity to caffeine.

Benomyl↗
PubMed1999

Interaction of bundled Ser-rich amphiphilic peptides with phospholipid membranes.

To investigate properties of hydrophilic bundled peptides and their interactions with phospholipid membranes, bundled peptides named [Trp2]- and [Trp12]-4alpha-46S9, which are composed of four fragments of amphiphilic 24-mer peptide, were designed and synthesized. Tryptophan (Trp) was introduced at the 2nd position from the N-terminal or at the centre (12th) of the helix to monitor the peptide-lipid interaction. Circular dichroism measurements indicated that the peptides had low alpha-helicities in a buffer solution (pH 7.4) and also in the presence of dipalmitoyl-DL-3-phosphatidylcholine (DPPC) vesicles. In the presence of DPPC/dipalmitoyl-DL-3-phosphatidylglycerol (DPPG) (3:1) vesicles, the measurement could not be taken because of turbidity induced by vesicle aggregation. Both peptides had moderate perturbation activity for both the neutral and acidic vesicles at 25 degrees C. The perturbation patterns at 50 degrees C were much different from those at 25 degrees C and the maximum activity reached 100% at a low peptide concentration. The results of the measurement of membrane fusion activity of peptides showed a similar tendency to that found in the perturbation experiment. A quenching experiment indicated that the Trp2 and Trp12 residues in [Trp2]- and [Trp12]-4alpha-46S9 were scarcely embedded in neutral lipid membranes.

Amino Acid Sequence↗
PubMed1999

Arterial oxygen saturation in severely disabled people: effect of oral feeding in the sitting position.

Control of the circulatory and respiratory systems is especially important in severely disabled people. The purpose of this study was to clarify the response of hemoglobin oxygen saturation level (SpO(2)), pulse rate, and respiratory rate during oral feeding in severely disabled persons. Continuous measurement of these variables was done by pulse oximetry and respiratory inductance plethysmography under two experimental settings in eight severely disabled persons aged 14-28 yrs. Setting I consisted of the following three procedures: (a) a 30-min period in the supine position, (b) a 50-min period in a sitting position, and (c) a 30-min period in the supine position. Setting II consisted of the following four procedures: (a) a 30-min period before the meal in the supine position, (b) a nonspecified period in a sitting position during which the meal was taken, (c) a 30-min period after the meal in the same sitting position, and (d) a 30-min period in the supine position. Results showed that mean SpO(2) level decreased and mean pulse rate increased during the meal in almost all subjects. In many cases, pulse rate and SpO(2) level did not return to baseline values in the sitting position after the meal. These findings indicate that oral feeding of severely disabled persons in a sitting position places considerable stress on the circulatory system, the effects of which may last after the meal in some cases.

Adolescent↗
PubMed1999

Light-induced denaturation of bacteriorhodopsin solubilized by octyl-beta-glucoside.

The structural stability of bacteriorhodopsin (bR) solubilized by octyl-beta-glucoside was studied by measuring the denaturation kinetics under visible light irradiation and in the dark. The denaturation of bR solubilized by 50 mM octyl-beta-glucoside was very slow at room temperature when it was left in the dark. However, its spontaneous denaturation was accelerated when the solubilized bR was irradiated by visible light. The denaturation kinetics under visible light irradiation and in the dark could be well described by a single decay constant. The activation energy for the denaturation of bR was estimated from the temperature dependence of decay time constants. The activation energy under visible light irradiation was 12.5 kcal/mol, which was much smaller than the corresponding value in the dark, 26.2 kcal/mol. These results strongly suggest that some of the photointermediate states are less stable than the ground state of bR. The critical temperature and the activation energy for denaturation of bR in the solubilized state were much lower than those in the 2D crystalline state. Comparing the denaturation behavior in the 2D crystalline state and that in the octyl-beta-glucoside-solubilized state, our findings suggest that protein-protein interaction contributes to the stability of this protein.

Bacteriorhodopsins↗
PubMed1999

Conservation of histone binding and transcriptional repressor functions in a Schizosaccharomyces pombe Tup1p homolog.

The Ssn6p-Tup1p corepressor complex is important to the regulation of several diverse genes in Saccharomyces cerevisiae and serves as a model for corepressor functions. To investigate the evolutionary conservation of these functions, sequences homologous to the S. cerevisiae TUP1 gene were cloned from Kluyveromyces lactis (TUP1) and Schizosaccharomyces pombe (tup11(+)). Interestingly, while the K. lactis TUP1 gene complemented an S. cerevisiae tup1 null mutation, the S. pombe tup11(+) gene did not, even when expressed under the control of the S. cerevisiae TUP1 promoter. However, an S. pombe Tup11p-LexA fusion protein repressed transcription of a corresponding reporter gene, indicating that this Tup1p homolog has intrinsic repressor activity. Moreover, a chimeric protein containing the amino-terminal Ssn6p-binding domain of S. cerevisiae Tup1p and 544 amino acids from the C-terminal region of S. pombe Tup11p complemented the S. cerevisiae tup1 mutation. The failure of native S. pombe Tup11p to complement loss of Tup1p functions in S. cerevisiae corresponds to an inability to bind to S. cerevisiae Ssn6p in vitro. Disruption of tup11(+) in combination with a disruption of tup12(+), another TUP1 homolog gene in S. pombe, causes a defect in glucose repression of fbp1(+), suggesting that S. pombe Tup1p homologs function as repressors in S. pombe. Furthermore, Tup11p binds specifically to histones H3 and H4 in vitro, indicating that both the repression and histone binding functions of Tup1p-related proteins are conserved across species.

Amino Acid Sequence↗
PubMed1999

The Ha locus of wheat: identification of a polymorphic region for tracing grain hardness in crosses.

The grain softness proteins or friabilins are known to be composed of three main components: puroindoline a, puroindoline b, and GSP-1. cDNAs for GSP-1 have previously been mapped to group-5 chromosomes and their location on chromosome 5D is closely linked to the grain hardness (Ha) locus of hexaploid wheat. A genomic DNA clone containing the GSP-1 gene (wGSP1-A1) from hexaploid wheat has been identified by fluorescent in situ hybridization as having originated from the distal end of the short arm of chromosome 5A. A genomic clone containing the gene (wGSP1-D1) was also isolated from Aegilops tauschii, the donor of the D genome to bread wheat. There are no introns in the GSP-1 genes, and there is high sequence identity between wGSP1-A1 and wGSP1-D1 up to 1 kb 5' and 300 bp 3' to wGSP1-D1. However, regions further upstream and downstream of wGSP1-D1 share no significant sequence identity to corresponding sequences in wGSP1-A1. These regions therefore identified potentially valuable sequences for tracing the Ha locus through assaying polymorphic DNA sequences. The sequence from 300 to 500 bp 3' to wGSP1-D1 (wGSP1-D13) was mapped to the Ha locus in a mapping population. wGSP1-D13 was also tightly linked to genes for puroindoline a and puroindoline b which have been previously mapped to be at the Ha locus. In addition wGSP1-D13 was used to detect RFLPs between near isogenic soft and hard Falcon lines and in a random selection of soft and hard wheats.

Base Sequence↗