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Y Fukushima

Publications and source records attributed to Y Fukushima.

At least 91 records · Page 5Linked to original sources
PubMed2000

Identification of BPESC1, a novel gene disrupted by a balanced chromosomal translocation, t(3;4)(q23;p15.2), in a patient with BPES.

The blepharophimosis syndrome (BPES) is a rare genetic disorder characterized by blepharophimosis, ptosis, epicanthus inversus, and telecanthus. In type I, BPES is associated with female infertility, while in type II, the eyelid defect occurs by itself. The BPES syndrome has been mapped to 3q23. Previously, we constructed a YAC-, PAC-, and cosmid-based physical map surrounding the 3q23 translocation breakpoint of a t(3;4)(q23;p15.2) BPES patient, containing a 110-kb PAC (169-C 10) and a 43-kb cosmid (11-L 10) spanning the breakpoint. In this report, we present the identification of BPESC1 (BPES candidate 1), a novel candidate gene that is disrupted by the translocation on chromosome 3. Cloning of the cDNA has been performed starting from a testis-specific EST, AI032396, found in cosmid 11-L 10. The cDNA sequence of BPESC1 is 3518 bp in size and contains an open reading frame of 351 bp. No significant similarities with known proteins have been found in the sequence databases. BPESC1 contains three exons and spans a genomic fragment of 17.5 kb. Expression of BPESC1 was observed in adult testis tissue. We performed mutation analysis in 28 unrelated familial and sporadic BPES patients, but, apart from the disruption by the translocation, found no other disease-causing mutations. These data make it unlikely that BPESC1 plays a major role in the pathogenesis of BPES.

Adult↗
PubMed2000

p110beta is up-regulated during differentiation of 3T3-L1 cells and contributes to the highly insulin-responsive glucose transport activity.

Activation of p85/p110 type phosphatidylinositol kinase is essential for aspects of insulin-induced glucose metabolism, including translocation of GLUT4 to the cell surface and glycogen synthesis. The enzyme exists as a heterodimer containing a regulatory subunit (e.g. p85alpha) and one of two widely distributed isoforms of the p110 catalytic subunit: p110alpha or p110beta. In the present study, we compared the two isoforms in the regulation of insulin action. During differentiation of 3T3-L1 cells into adipocytes, p110beta was up-regulated approximately 10-fold, whereas expression of p110alpha was unaltered. The effects of the increased p110 expression were further assessed by expressing epitope tagged p110beta and p110alpha in 3T3-L1 cells using adenovirus transduction systems, respectively. In vitro, the basal lipid kinase activity of p110beta was lower than that of p110alpha. When p110alpha and p110beta were overexpressed in 3T3-L1 adipocytes, exposing cells to insulin induced each of the subunits to form complexes with p85alpha and tyrosine-phosphorylated IRS-1 with similar efficiency. However, whereas the kinase activity of p110beta, either endogenous or exogeneous, was markedly enhanced by insulin stimulation, only very small increases of the activity of p110alpha were observed. Interestingly, overexpression of p110beta increased insulin-induced glucose uptake by 3T3-L1 cells without significantly affecting basal glucose transport, whereas overexpression of p110alpha increased both basal and insulin-stimulated glucose uptake. Finally, microinjection of anti-p110beta neutralizing antibody into 3T3-L1 adipocytes abolished insulin-induced translocation of GLUT4 to the cell surface almost completely, whereas anti-p110alpha neutralizing antibody did only slightly. Together, these findings suggest that p110beta plays a crucial role in cellular activities evoked acutely by insulin.

3T3 Cells↗
PubMed2000

Structural analysis of a rare rearranged Y chromosome and its bearing on genotype-phenotype correlation.

We report on a 9-year-old boy with a rare rearranged Y chromosome and borderline short stature (-2.0 SD). Standard metaphase chromosome analysis indicated a 46,X,i(Y)(q1O) karyotype, but high resolution G-banding showed an asymmetric band pattern for the rearranged Y chromosome. FISH and DNA studies for a total of 15 different Y chromosomal loci or regions showed that the rearranged Y chromosome was accompanied by: 1) a partial deletion of the short arm pseudoautosomal region (PAR1) involving SHOX, with the breakpoint distal to DXYS85; and 2) a partial duplication of Yq, with the breakpoint proximal to DAZ. The karyotype was determined as 46,X,?i(Y)(q1O).ish der(Y)(Yqter--> Yp11.3::Yq11.2-->Yqter)(DAZ++,DYZ3+,SRY +, SHOX-). The X chromosome and the autosomes were normal. The results suggest that haploinsufficiency of SHOX is primarily responsible for the borderline short stature, and that the deletion of the PAR1 may result in spermatogenic failure due to defective X-Y pairing and recombination in the PAR1.

Child↗
PubMed2000

The N-terminal 34 residues of the 55 kDa regulatory subunits of phosphoinositide 3-kinase interact with tubulin.

There are five regulatory subunit isoforms of phosphoinositide 3-kinase (PI 3-kinase), which are classified into three groups: proteins of 85 kDa (p85alpha and p85beta), 55 kDa (p55alpha and p55gamma) and 50 kDa (p50alpha). Structural differences between the three groups reside in the N-terminus. To elucidate the unique functional role of the 55 kDa regulatory subunits, GST (glutathione S-transferase) fusion proteins containing a unique N-terminal portion consisting of a 34-amino-acid sequence of p55alpha or p55gamma (GST-p55alpha/gammaN(1-34)) were used as affinity matrices to screen rat brain cell extracts for proteins to which this portion binds specifically. A protein that bound was identified as beta-tubulin by protein sequencing. In addition, not only the beta isoform of tubulin, but also the alpha and gamma isoforms, were detected in the protein absorbed from cell lysates with GST-p55gammaN(1-34) and GST-p55alphaN(1-34) by immunoblotting. Indeed, the only regulatory subunit present in the purified microtubule assembly from rat brain was the 55 kDa isoform; neither 85 kDa nor 50 kDa subunits were detected. These results indicate endogenous binding of 55 kDa regulatory subunits of PI 3-kinase to tubulin in the brain. Finally, we measured tubulin-associated PI 3-kinase activity in CHO/IR cells overexpressing each of the five regulatory subunit isoforms. Only in cells expressing p55alpha or p55gamma was there a significant elevation of tubulin-associated PI 3-kinase activity in response to insulin. These results suggest that the p55alpha and p55gamma regulatory subunits have important roles in regulating PI 3-kinase activity, particularly for microtubules at the cell periphery.

Amino Acid Sequence↗
PubMed2000

Identification of a gene disrupted by inv(11)(q13.5;q25) in a patient with left-right axis malformation.

An inv(11)(q13.5;q25) inversion was previously identified in a 9-month-old male patient with complex cyanotic heart defects, altered lung lobation, symmetric liver, and abnormally lobulated spleen (polysplenia). This chromosomal rearrangement was inherited from the phenotypically normal father. We termed these regions DHTX-A (disrupted in heterotaxy)-- A at 11q13.5 and DHTX-B at 11q25. Here, we report the isolation and characterization of the inversion breakpoints and the gene that is disrupted by the DHTX-A breakpoint. The putative DHTX is identical to the UVRAG gene, which was originally identified as a gene that complements the UV sensitivity of xeroderma pigmentosum complementation group C. The 4-kb mRNA was found to be encoded by a large gene, at least 300 kb long, composed of 15 exons. The function of the gene product remains largely unknown. However, the near central portion of the UVRAG protein is predicted to contain a coiled-coil domain, which has been implicated in mediating protein-protein interactions. Southern analyses and fluorescence in situ hybridization (FISH) revealed that the DHTX-A breakpoint in the patient and his father lies within the intron between exons 6 and 7 of UVRAG. Northern blot analysis indicated strong expression in human fetal and adult tissues and in mouse embryonic day-7 and adult tissues, respectively. Whole mount in situ hybridization also showed that the Uvrag gene is expressed in the presomite-stage embryo. Several hypotheses are discussed to explain the relationship between the chromosomal inversion and the accompanying phenotypes.

Amino Acid Sequence↗
PubMed2000

Long-lasting binding of IT-066 to human histamine H2 receptor.

Based on animal models, IT-066, a histamine H2-receptor antagonist, is reported to possess potent and long-lasting antagonisms on histamine H2 receptor (H2R) -mediated effects. However, no reports have been published concerning its interaction with the human H2R. The aim of this study is to characterize its interaction with human H2R. Chinese hamster ovary cell lines stably expressing human H2Rs were obtained. The effects of IT-066, famotidine, and ranitidine on tiotidine binding and histamine-stimulated cAMP production were analyzed. IT-066 inhibited [3H]tiotidine binding and histamine-stimulated cAMP production more potently than famotidine or ranitidine. In addition, preincubation with 10(-5) M IT-066, but not with 10(-5) M famotidine or 10(-4) M ranitidine, had marked inhibitory effects long after extensive washing. Paraformaldehyde fixation of the cells blunted inhibition of [3H]tiotidine binding induced by preincubation with IT-066, but not that by preincubation with famotidine or ranitidine. IT-066 has potent and long-lasting antagonisms on human H2R. At least one of the IT-066 binding sites is not shared by famotidine, ranitidine, or tiotidine and is affected by paraformaldehyde fixation.

Animals↗
PubMed2000

Domain-specific mutations in TGFB1 result in Camurati-Engelmann disease.

Camurati-Engelmann disease (CED, MIM 131300) is an autosomal dominant, progressive diaphyseal dysplasia characterized by hyperosteosis and sclerosis of the diaphyses of long bones. We recently assigned the CED locus to an interval between D19S422 and D19S606 at chromosome 19q13.1-q13.3, which two other groups confirmed. As the human transforming growth factor-1 gene (TGFB1) is located within this interval, we considered it a candidate gene for CED.

Base Sequence↗
PubMed2000

An autosomal dominant posterior polar cataract locus maps to human chromosome 20p12-q12.

We assigned the locus for a previously reported new type of autosomal dominant posterior polar cataract (CPP3) to 20p12-q12 by a genome-wide two-point linkage analysis with microsatellite markers. CPP3 is characterized by progressive, disc-shaped, posterior subcapsular opacity. The disease was seen in 10 members of a Japanese family and transmitted in an autosomal dominant fashion through four generations. We obtained a maximum lod score (Zmax) of 3.61 with a recombination fraction (theta) of 0.00 for markers D20S917, D20S885 and D20S874. Haplotype analysis gave the disease gene localization at a 15.7-cM interval between D20S851 and D20S96 loci on chromosome 20p12-q12. Since the BFSP1 that encodes the lens-specific beaded filament structural protein 1 (filensin) has been mapped around the CPP3 region, we performed sequence analysis on its entire coding region. However, no base substitution or deletion was detected in the CPP3 patients. The mapping of the CPP3 locus to 20p12-q12 not only expands our understanding of the genetic heterogeneity in autosomal dominant posterior polar cataracts but also is a clue for the positional cloning of the disease gene.

Base Sequence↗
PubMed2000

Genetic mapping of the Camurati-Engelmann disease locus to chromosome 19q13.1-q13.3.

Camurati-Engelmann disease (CED [MIM 131300]), or progressive diaphyseal dysplasia, is an autosomal dominant sclerosing bone dysplasia characterized by progressive bone formation along the periosteal and endosteal surfaces at the diaphyseal and metaphyseal regions of long bones and cranial hyperostosis, particularly at the skull base. The gene for CED, or its chromosomal localization, has not yet been identified. We performed a genomewide linkage analysis of two unrelated Japanese families with CED, in which a total of 27 members were available for this study; 16 of them were affected with the disease. Two-point linkage analysis revealed a maximum LOD score of 7.41 (recombination fraction.00; penetrance 1.00) for the D19S918 microsatellite marker locus. Haplotype analysis revealed that all the affected individuals shared a common haplotype observed, in each family, between D19S881 and D19S606, at chromosome 19q13.1-q13.3. These findings, together with a genetic distance among the marker loci, indicate that the CED locus can be assigned to a 15.1-cM segment between D19S881 and D19S606.

Camurati-Engelmann Syndrome↗
PubMed2000

Sex-dependent regulation of hepatic peroxisome proliferation in mice by trichloroethylene via peroxisome proliferator-activated receptor alpha (PPARalpha).

The mechanism of trichloroethylene-induced liver peroxisome proliferation and the sex difference in response was investigated using wild-type Sv/129 and peroxisome proliferator-activated receptor alpha (PPARalpha)-null mice. Trichloroethylene treatment (0.75 g/kg for 2 weeks by gavage) resulted in liver peroxisome proliferation in wild-type mice, but not in PPARalpha-null mice, suggesting that trichloroethylene-induced peroxisome proliferation is primarily mediated by PPARalpha. No remarkable sex difference was observed in induction of peroxisome proliferation, as measured morphologically, but a markedly higher induction of several enzymes and PPARalpha protein and mRNA was found in males. On the other hand, trichloroethylene induced liver cytochrome P450 2E1, the principal enzyme responsible for metabolizing trichloroethylene to chloral hydrate, only in males, which resulted in similar expression levels in both sexes after the treatment. Trichloroethylene influenced neither the level of catalase, an enzyme involved in the reduction of oxidative stress, nor aldehyde dehydrogenase, the main enzyme catalyzing the conversion to trichloroacetic acid. These results suggest that trichloroethylene treatment causes a male-specific PPARalpha-dependent increase in cellular oxidative stress.

Animals↗
PubMed2000

A novel non-pathogenetic polymorphism of the APC gene in a patient with familial adenomatous polyposis coli.

DISORDER: Familial adenomatous polyposis coli. ETHNICITY OF PATIENT: Japanese. GENE: APC. GENBANK ACCESSION NUMBER: M 74088. CHROMOSOMAL ASSIGNMENT: 5q21. TYPE OF DNA VARIANT: A germline missense mutation. A germline nonsense mutation. MUTATION: CGG (Arg, wild type) to TGG (Trp) substitution at codon 88 in exon 3 of the APC gene. CGA (Arg, wild type) to TGA (term.) at codon 213 in exon 5 of the APC gene. ALLELIC FREQUENCY: <0.014 (missense mutation, TGG at codon 88). METHOD OF MUTATION DETECTION: PCR-SSCP/direct sequencing.

Adenomatous Polyposis Coli↗
PubMed2000

Role of potassium channels in catecholamine secretion in the rat adrenal gland.

We elucidated the functional contribution of K(+) channels to cholinergic control of catecholamine secretion in the perfused rat adrenal gland. The small-conductance Ca(2+)-activated K(+) (SK(Ca))-channel blocker apamin (10-100 nM) enhanced the transmural electrical stimulation (ES; 1-10 Hz)- and 1, 1-dimethyl-4-phenyl-piperazinium (DMPP; 5-40 microM)-induced increases in norepinephrine (NE) output, whereas it did not affect the epinephrine (Epi) responses. Apamin enhanced the catecholamine responses induced by acetylcholine (6-200 microM) and methacholine (10-300 microM). The putative large-conductance Ca(2+)-activated K(+) channel blocker charybdotoxin (10-100 nM) enhanced the catecholamine responses induced by ES, but not the responses induced by cholinergic agonists. Neither the K(A) channel blocker mast cell degranulating peptide (100-1000 nM) nor the K(V) channel blocker margatoxin (10-100 nM) affected the catecholamine responses. These results suggest that SK(Ca) channels play an inhibitory role in adrenal catecholamine secretion mediated by muscarinic receptors and also in the nicotinic receptor-mediated secretion of NE, but not of Epi. Charybdotoxin-sensitive Ca(2+)-activated K(+) channels may control the secretion at the presynaptic site.

Acetylcholine↗
PubMed2000

Interaction of SK(Ca) channels and L-type Ca(2+) channels in catecholamine secretion in the rat adrenal gland.

We elucidated the interaction of small-conductance Ca(2+)-activated K(+) (SK(Ca)) channels and L-type Ca(2+) channels in muscarinic receptor-mediated control of catecholamine secretion in the isolated perfused rat adrenal gland. The muscarinic agonist methacholine (10-300 microM) produced concentration-dependent increases in adrenal output of epinephrine and norepinephrine. The SK(Ca) channel blocker apamin (1 microM) enhanced the methacholine-induced catecholamine responses. The facilitatory effect of apamin on the methacholine-induced catecholamine responses was not observed during treatment with the L-type Ca(2+) channel blocker nifedipine (3 microM) or Ca(2+)-free solution. Nifedipine did not affect the methacholine-induced catecholamine responses, but it inhibited the responses during treatment with apamin. The L-type Ca(2+) channel activator Bay k 8644 (1 microM) enhanced the methacholine-induced catecholamine responses, whereas the enhancement of the methacholine-induced epinephrine and norepinephrine responses were prevented and attenuated by apamin, respectively. These results suggest that SK(Ca) channels are activated by muscarinic receptor stimulation, which inhibits the opening of L-type Ca(2+) channels and thereby attenuates adrenal catecholamine secretion.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed2000

A case of XY pure gonadal dysgenesis with 46,XYp-/47,XXYp- karyotype whose gonadoblastoma was removed laparoscopically.

A case of pure gonadal dysgenesis was investigated. The patient was an 18-year-old Japanese woman with a history of primary amenorrhea. She had poorly developed breasts, a hypoplastic uterus, a normal vagina and infantile genitalia. The patient's karyotype was 46,XYp-/ 47,XXYp-. Microsatellite analysis revealed that the X chromosomes of this patient originated from one of the two maternal X chromosomes. DNA analysis of the Y chromosome revealed that she had a deletion of SRY (the sex-determining region on the Y chromosome). She underwent laparoscopic gonadectomies with a final pathology consistent with gonadoblastoma. Laparoscopic surgery is recommended as it is much less invasive and associated with rapid postoperative recovery.

Adolescent↗
PubMed2000

Increased levels of surfactant protein A and D in bronchoalveolar lavage fluids in patients with bronchial asthma.

Surfactant proteins (SP)-A and SP-D are collagen-like glycoproteins belonging to the "collectin" class of C-type lectins, which are primarily synthesized in type II cells. Recent studies reported the possibility of local production of SP-A and SP-D in the airways, but the amounts of surfactant proteins in patients with bronchial asthma have not been studied. The composition of surfactant proteins in mild, stable asthmatics in the first lavage as bronchial lavage (BL) and the second and third lavages consecutively as alveolar lavages (AL) were therefore, analysed separately. The co-relationships in the BL between the amounts of surfactant proteins and those of fucose, which is one of the markers of submucosal secretion were also analysed. Increased amounts of SP-A in BL and AL of in asthmatics were found as compared with those in controls. A high concentration of SP-D in the AL asthma patients was also found. The levels of SP-A correlated with those of fucose in patients with bronchial asthma (r=0.849, p<0.01). The observations in the present study suggested that surfactant protein A may be secreted from the airways with allergic inflammation in a different manner from the alveoli. The increased levels of surfactant proteins A and D may play a protective role in an allergic inflammation in the pathogenesis of bronchial asthma.

Adult↗