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N Seki

Publications and source records attributed to N Seki.

At least 91 records · Page 5Linked to original sources
PubMed1999

Orthologues of the Caenorhabditis elegans longevity gene clk-1 in mouse and human.

The clk-1 gene was isolated from the long-lived mutant of Caenorhabditis elegans and was suggested to play a biological role in longevity (Ewbank et al., 1997, Science 275: 980-983). The primary structure of CLK-1 showed a significant homology to Saccharomyces cerevisiae Coq7p/Cat5p, which is required for the biosynthesis of ubiquinone and the derepression of gluconeogenic genes. In the present study, we isolated and characterized human and mouse orthologues of the COQ7/CLK-1 gene. Sequence analysis of both the human and the mouse COQ7 cDNAs showed an open reading frame composed of 217 amino acids with calculated molecular mass of 24,309 and 24,044 Da, respectively. Homology search revealed that human COQ7 showed 85% identity to mouse COQ7, 89% identity to rat COQ7, 53% identity to C. elegans CLK-1, and 37% identity to S. cerevisiae Coq7p/Cat5p. Zoo blot analysis implied that the COQ7 gene was well conserved among mammal, bird, and reptile genomes. Tissue blot analysis showed that human COQ7 is dominantly transcribed in heart and skeletal muscle. Genomic analyses revealed that the human COQ7 gene is composed of six exons spanning 11 kb of human genome as a single-copy gene. Radiation hybrid mapping assigned the COQ7 gene to human chromosome 16p12.3-p13.11.

Amino Acid Sequence↗
PubMed1999

Isolation and characterization of a novel human gene (HFB30) which encodes a protein with a RING finger motif.

A human cDNA, HFB30, encoding a novel protein that contains a RING finger (C3HC4-type zinc finger) motif was isolated. This cDNA clone consists of 3056 nucleotides and encodes an open reading frame of a 474 amino acid protein. From RT-PCR analysis, the messenger RNA was ubiquitously expressed in various human tissues. The gene was located to the chromosome 5q23.3-q31.1 region by PCR-based analyses with both a human/rodent monochromosomal hybrid cell panel and a radiation hybrid mapping panel. Furthermore, the gene consists of nine exons that span about 20 kb of genome DNA.

Amino Acid Sequence↗
PubMed1999

PKCnu, a new member of the protein kinase C family, composes a fourth subfamily with PKCmu.

Members of the protein kinase C (PKC) family of serine/threonine kinases are thought to play critical roles in the regulation of cellular differentiation and proliferation in many cell types. An additional member of the PKC family was identified through human expressed sequence tag (EST) database search and its full length cDNA was isolated. Sequence analysis revealed that the predicted translation product was composed of 890 amino acid residues and that the protein has 77.3% similarity to human PKC mu (PKCmu) and 77. 4% similarity to mouse PKD (the mouse homolog of PKCmu). We designated the new member as protein kinase C nu (PKCnu). The PKCnu messenger RNA was ubiquitously expressed in various tissues when analyzed by Northern blots and reverse transcriptase-coupled polymerase chain reaction (PCR) analyses. The chromosomal location of the gene was determined between markers WI-9798 and D2S177 on chromosome 2p21 region by PCR-based methods with both a human/rodent monochromosomal hybrid cell panel and a radiation hybrid mapping panel.

Amino Acid Sequence↗
PubMed1999

p73 at chromosome 1p36.3 is lost in advanced stage neuroblastoma but its mutation is infrequent.

p73, a novel p53 family member, is a recently identified candidate neuroblastoma (NBL) suppressor gene mapped at chromosome 1p36.33 and was found to inhibit growth and induce apoptosis in cell lines. To test the hypothesis that p73 is a NBL suppressor gene, we analysed the p73 gene in primary human NBLs. Loss of heterozygosity (LOH) for p73 was observed in 19% (28/151) of informative cases which included 92 mass-screening (MS) tumors. The high frequency of p73 LOH was significantly associated with sporadic NBLs (9% vs 34%, P<0.001), N-myc amplification (10% vs 71%, P<0.001), and advanced stage (14% vs 28%, P<0.05). Both p73alpha and p73beta transcripts were detectable in only 46 of 134 (34%) NBLs at low levels by RT-PCR methods, while they were easily detectable in most breast cancers and colorectal cancers under the same conditions. They found no correlation between p73 LOH and its expression levels (P>0.1). We found two mutations out of 140 NBLs, one somatic and one germline, which result in amino acid substitutions in the C-terminal region of p73 which may affect transactivation functions, though, in the same tumor samples, no mutation of the p53 gene was observed as reported previously. These results suggest that allelic loss of the p73 gene may be a later event in NBL tumorigenesis. However, p73 is infrequently mutated in primary NBLs and may hardly function as a tumor suppressor in a classic Knudson's manner.

Chromosome Mapping↗
PubMed1999

Structure, expression profile and chromosomal location of an isolog of DNA-PKcs interacting protein (KIP) gene.

A novel DNA-PKcs interacting protein, KIP (kinase interacting protein), was recently isolated using a two-hybrid analysis which showed a significant homology to calcineurin B. We found other ESTs showing significant similarity to KIP gene in the dbEST database and isolated a cDNA clone which encodes a 187 amino acid polypeptide from a human fetal brain cDNA library. This protein (termed KIP2 for kinase interacting protein 2) has sequence homology to KIP (46% identical and 64% similarity). RT-PCR analysis showed that the messenger RNA was ubiquitously expressed in various human tissues. Based on PCR-based analysis with a radiation hybrid cell panel and fluorescence in situ hybridization, the gene was localized to the q24 region of chromosome 15.

Amino Acid Sequence↗
PubMed1999

Identification of a genetic risk factor for systemic juvenile rheumatoid arthritis in the 5'-flanking region of the TNFalpha gene and HLA genes.

OBJECTIVE: To study polymorphisms in the 5'-flanking promoter/enhancer region of the tumor necrosis factor alpha (TNFalpha) gene and in the coding regions of HLA class I and class II genes, in order to better understand the genetic background of juvenile rheumatoid arthritis (JRA). METHODS: One hundred eleven Japanese JRA patients (50 with systemic disease, 29 with pauciarticular disease, and 32 with polyarticular disease) and 575 healthy Japanese subjects were examined for the allele frequencies of the TNFalpha, HLA-A, and HLA class II (DRB1, DRB3, DRB4, DRB5, DQA1, DQB1, DPA1, and DPB1) genes, by DNA typing using the polymerase chain reaction-sequence-specific oligonucleotide probe method. RESULTS: The frequencies of the polymorphic allele at positions -1,031 (T to C substitution, termed -1,031C), -863 (C to A, termed -863A), and -857 (C to T, termed -857T) of the TNFalpha gene in patients with systemic JRA, but not in those with polyarticular or pauciarticular JRA, were significantly higher than in the healthy controls. The allele frequencies of DRB1*0405 and DQB1*0401 in systemic JRA, but not in the other JRA types, were significantly higher than in controls. Linkage analysis showed that the presence of both the TNFalpha -857T allele and DRB1*0405 yielded a significantly increased odds ratio (3.84), while the presence of only 1 of them did not yield a high odds ratio (0.87 and 1.58). CONCLUSION: The -1,031C/-863A allele and the -857T allele of the TNFalpha gene, both of which are related to high production of tumor necrosis factor alpha, are associated with systemic JRA. The -857T allele may enhance the effect of the DRB1*0405/DQB1*0401 haplotype in predisposing to development of systemic JRA.

Arthritis, Juvenile↗
PubMed1999

Urachal cyst associated with a suprapubic sinus.

Urachal anomalies are frequent and may exhibit many anatomical variations. We report a case of a urachal cyst that had a sinus tract extending to the lower abdomen just above the pubic symphysis. Histologic examination of the specimens showed a squamous-epithelium-lined sinus tract and a columnar-epithelium-lined cyst, which suggested a developmental disorder. This may be an extremely rare case where the urachal cyst opened into the suprapubic sinus.

Child, Preschool↗
PubMed1999

Isolation and chromosomal assignment of human genes encoding cofactor of LIM homeodomain proteins, CLIM1 and CLIM2.

Cofactors of LIM homeodomain proteins (CLIM) are transcriptional activators that associate with the LIM homeoproteins and coordinate transcription. LIM homeoproteins and CLIMs are involved in a variety of developmental processes. Two CLIMs, CLIM1 and CLIM2, have been identified in the mouse. Here we report the isolation of human CLIM1 and CLIM2 cDNAs and the determination of their chromosome locations by using a human-rodent monochromosomal hybrid cell panel and a radiation hybrid mapping panel. The proteins deduced from human CLIM1 and CLIM2 cDNAs were composed of 373 and 375 amino acids, respectively, and had 97.3% and 98.7% amino acid identity, respectively, to their mouse counterparts. Human CLIM1 and CLIM2 proteins were 75.5% identical. Human CLIM1 and CLIM2 genes were mapped to the chromosome on 4p15.3 and 10q24-q25 regions, respectively. Mapping of a pair of developmentally important genes may provide new clues to the understanding of genetic disorders caused by these chromosome regions.

Amino Acid Sequence↗
PubMed1999

A novel human gene whose product shares significant homology with the bovine brain-specific protein p25 on chromosome 5p15.3.

Here, we report on the sequence features and chromosomal location of a novel human gene which shares significant homology with the bovine brain-specific protein p25. Based on polymerase chain reaction analysis with a human/rodent monochromosomal hybrid cell panel and a radiation hybrid panel, the gene was mapped on to p15.3 region of chromosome 5.

Amino Acid Sequence↗
PubMed1999

The human regulator of G-protein signaling protein 6 gene (RGS6) maps between markers WI-5202 and D14S277 on chromosome 14q24.3.

The recently discovered regulators of G-protein signaling proteins, termed the RGS family, have been shown to modulate the functioning of G-proteins by activating the intrinsic guanosine triphosphatase (GTPase) activity of the alpha subunits. Here, we report the chromosomal location and tissue expression of the human regulator of RGS6 gene. The messenger RNA was ubiquitously expressed in various tissues. Polymerase chain reaction (PCR)-based analysis with a human/rodent monochromosomal hybrid panel and a radiation hybrid panel indicated that the gene was mapped between genetic markers WI-5202 and D14S277 on chromosome 14q24.3 region.

Base Sequence↗
PubMed1999

Cloning, tissue expression, and chromosomal assignment of human MRJ gene for a member of the DNAJ protein family.

The DnaJ protein family consists of proteins with a highly conserved amino acid stretch called the "J-domain". A cDNA clone encoding a new protein with a J-domain was isolated from a human fetal brain cDNA library. This new member of the DnaJ family of 241 amino acid residues showed 94% identity with mouse Mrj (accession number, AF035962) and 71% identity with mouse Msj-1 (accession number, U95607) along its entire sequence. Reverse transcription-coupled polymerase chain reaction (RT-PCR) analysis showed the messenger RNA was ubiquitously expressed in various human tissues. The chromosomal location of the gene was determined by PCR-based analyses with both a human/rodent monochromosomal hybrid cell panel and a radiation hybrid panel to map on chromosome 11q25 region.

Amino Acid Sequence↗
PubMed1999

Isolation and chromosomal mapping of a novel human gene showing homology to Na+/PO4 cotransporter.

We isolated a cDNA clone which shows a significant similarity with the renal Na+/phosphate cotransporter (NPT) from a human intestine mucosa cDNA library. The cDNA is 2626 bases long, with one open reading frame encoding a protein of 497 amino acids. The deduced amino acids sequence shows an overall homology of 48% with the human renal NPT1 protein. This gene is expressed in intestine, colon, liver, and pancreas. Thus, this gene may code for intestinal type NPT or closely related proteins. The chromosomal location of the gene was determined on the chromosome 6p21.3-p22 region by polymerase chain reaction-based analysis with both a human/rodent mono-chromosomal hybrid cell panel and a radiation hybrid mapping panel.

Amino Acid Sequence↗
PubMed1999

Isolation and chromosomal assignment of a human gene encoding protein inhibitor of activated STAT3 (PIAS3).

Mouse PIAS3 (protein inhibitor of activated STAT3) is a specific inhibitor of STAT3 that downregulates its signaling pathway. Here we report the isolation and chromosome mapping of the human PIAS3 gene. Human PIAS3 cDNA encoded a predicted protein of 619 aa which has 83% overall amino acid identity to the mouse counterpart. Based on polymerase chain reaction assisted analysis of a human/rodent mono-chromosomal hybrid cell panel and a radiation hybrid mapping panel, the human PIAS3 gene was mapped to the chromosome 1q21 region. Mapping of a crucial gene in modulating the STAT3 signaling pathway may provide new clues to the understanding of malignancies or genetic disorders caused by this chromosome region.

Amino Acid Sequence↗
PubMed1999

Cloning, expression analysis, and chromosomal localization of a novel butyrophilin-like receptor.

We isolated a cDNA clone which shows a similarity with human butyrophilin from a human colon mucosa cDNA library. The cDNA is 1964 bases long, with one open reading frame encoding a protein of 433 amino acids. The deduced amino acid sequence shows an overall homology of 36.5% with the human butyrophilin protein. This gene is mainly expressed in small intestine, colon, testis, and leukocytes. The chromosomal location of the gene was determined on the chromosome 5q35 region by polymerase chain reaction-based analysis with both a human/rodent monochromosomal hybrid cell panel and a radiation hybrid mapping panel.

Amino Acid Sequence↗
PubMed1999

Isolation, tissue expression, and chromosomal assignment of a human LIM protein gene, showing homology to rat enigma homologue (ENH).

Rat ENH (Enigma homolog) is a LIM domain protein that associates with protein kinase C in an isoform-specific manner. We have identified a human cDNA which shares a significant sequence homology with rat ENH. The isolated cDNA clone, designated human ENH (hENH), was 3287 bp in length and encoded a predicted protein of 596 amino acids which had 88% overall identity to rat ENH protein. Northern blot analysis revealed that 1.9 kb of the hENH messenger RNA was predominantly expressed in heart and skeletal muscle, while 5.6 kb of the hENH messenger RNA was ubiquitously expressed in various human tissues. The chromosomal location of the gene was determined on chromosome 4q22 region, between markers WI-2900 and WI-3273, by polymerase chain reaction (PCR)-based analyses using both a human/rodent monochromosomal hybrid cell panel and a radiation hybrid mapping panel.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Serum C-reactive protein as a prognostic factor in patients with epithelial ovarian cancer.

OBJECTIVE: It is well known that the serum level of Interleukin-6 (IL-6) correlates with the level of C-reactive protein (CRP). The purpose of this study is to determine the significance of CRP as a prognostic factor in epithelial ovarian cancer. STUDY DESIGN: The present study is comprised of 120 patients with epithelial ovarian cancer from 1985 to 1992. In this study, CRP levels above 50 mg/l were considered high CRP. Univariate and multivariate analyses were performed to identify clinicopathological variables associated with poor survival. RESULTS: The serum CRP value was significantly associated with the volume of ascites (P = 0.000004). Univariate analysis showed that the FIGO stage, primary tumour diameter, size of residual tumour, histologic grade, volume of ascites and high serum level of CRP were significant prognostic factors. Cox's multivariate proportional hazard model showed that histologic grade was the most important prognostic factor (P = 0.0026). FIGO stage and volume of ascites were also independent factors for 5-year survival (P = 0.0310 and P = 0.0216, respectively). However, the serum CRP value was not an independent prognostic factor. CONCLUSION: CRP is an adverse prognostic factor in univariate analysis, but not in multivariate analysis.

Adenocarcinoma, Clear Cell↗