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J Inazawa

Publications and source records attributed to J Inazawa.

At least 109 records · Page 6Linked to original sources
PubMed1997

A complete NotI restriction map covering the entire long arm of human chromosome 11.

BACKGROUND: Human chromosome 11 is one of the autosomes on which many disease genes have been mapped. Many different types of map, including a radiation hybrid map, a genetic map, and an STS-content YAC map, have been constructed for the chromosome. However, a physical map providing accurate physical distances has not yet been established. A chromosome-wide NotI restriction map was constructed to understand the overall feature of the genome organization and to facilitate the positional cloning of disease genes. RESULTS: A complete NotI restriction map of the entire long arm of human chromosome 11 was constructed using linking-clone mapping. This physical map covers 77.6Mb, from a pericentromeric NotI site to the terminus, and provides the most accurate ordering and distance estimation to date. We also mapped 138 sequence markers in the q13 region that have been poorly mapped previously. CONCLUSIONS: The restriction map of the entire long arm of human chromosome 11 is the longest restriction map of the human genome. This mapping has disclosed unique features regarding the organization of the chromosome, indicating that restriction sites of NotI, a CpG-recognition enzyme, are primarily distributed in R (or T) bands and that genetic distance is considerably longer in R (or T) bands than in G bands. The mapping, as well as the dense concentration of mapped markers within the q13 region, should help with positional cloning of the genes associated with various diseases.

Bacteriophage P1↗
PubMed1997

The whole nucleotide sequence and chromosomal localization of the gene for human metabotropic glutamate receptor subtype 6.

Metabotropic glutamate receptor subtype 6 (mGluR6) is restrictedly expressed in the retinal ON bipolar cells and ablation of mouse mGluR6 by gene targeting results in a loss of ON responses to light stimulus and impairs the detection of visual contrasts. We have isolated genomic clones containing the human mGluR6 gene and determined the whole nucleotide sequence of the mGluR6 gene. The transcription initiation site of the human mGluR6 gene has been identified using primer extension analysis in combination with reverse transcriptase-mediated polymerase chain reaction analysis of human retinal RNA, while the termination of the mGluR6 mRNA has been assigned by the analysis of rapid amplification of 3'-cDNA ends. The human mGluR6 gene consists of 16,742 base pairs with 10 exons separated by nine introns. The human mGluR6 is composed of 877 amino acid residues with a signal peptide of 24 amino acid residues and the mature protein shows a 94.6% homology with the rat counterpart. A CpG-rich island is present at exon 1 and its preceding putative promoter region and this unusual sequence, like several tissue-specific genes, may be important for a specific expression of the mGluR6 gene in the retinal bipolar cells. The human mGluR6 gene has been mapped to chromosome 5q35 by the analyses of blot hybridization of a DNA panel of human/mouse/hamster somatic cell hybrids and fluorescence in situ hybridization of human chromosomes. This study should provide the genetic basis for not only better understanding the molecular mechanism underlying a tissue-specific expression of the mGluR6 gene but also exploring a potential defect in human mGluR6 in a certain inherited eye disease.

Amino Acid Sequence↗
PubMed1997

HSF4, a new member of the human heat shock factor family which lacks properties of a transcriptional activator.

Heat shock transcription factors (HSFs) mediate the inducible transcriptional response of genes that encode heat shock proteins and molecular chaperones. In vertebrates, three related HSF genes (HSF1 to -3) and the respective gene products (HSFs) have been characterized. We report the cloning and characterization of human HSF4 (hHSF4), a novel member of the hHSF family that shares properties with other members of the HSF family yet appears to be functionally distinct. hHSF4 lacks the carboxyl-terminal hydrophobic repeat which is shared among all vertebrate HSFs and has been suggested to be involved in the negative regulation of DNA binding activity. hHSF4 is preferentially expressed in the human heart, brain, skeletal muscle, and pancreas. Transient transfection of hHSF4 in HeLa cells, which do not express hHSF4, results in a constitutively active DNA binding trimer which, unlike other members of the HSF family, lacks the properties of a transcriptional activator. Constitutive overexpression of hHSF4 in HeLa cells results in reduced expression of the endogenous hsp70, hsp90, and hsp27 genes. hHSF4 represents a novel hHSF that exhibits tissue-specific expression and functions to repress the expression of genes encoding heat shock proteins and molecular chaperones.

Amino Acid Sequence↗
PubMed1997

Molecular cloning of CISH, chromosome assignment to 3p21.3, and analysis of expression in fetal and adult tissues.

The murine cytokine inducible SH2-containing (Cis) protein gene (Cish) was recently cloned and shown to have a growth inhibitory function. We have isolated cDNAs coding for its human homologue (CISH) and assigned the gene to 3p21.3 by fluorescence in situ hybridization. Northern blot analysis showed CISH expression in various epithelial tissues including lung and kidney, in which tumors frequently exhibit 3p21.3 deletions.

Adult↗
PubMed1997

Mammalian occludin in epithelial cells: its expression and subcellular distribution.

Occludin has been identified from chick liver as a novel integral membrane protein localizing at tight junctions, and the cDNA encoding its mammalian homologue was identified very recently (Ando-Akatsuka, Y., M. Saitou, T. Hirase, M. Kishi, A. Sakakibara, M. Itoh, S. Yonemura, M. Furuse, Sh. Tsukita, J. Cell Biol. 133, 43-47 (1996)). Here we describe the basic properties of mammalian occludin in epithelial cells at the DNA, RNA, and protein levels. The human occludin gene was mapped to chromosome band 5q13.1 by fluorescent in situ hybridization. Northern blotting identified several occludin mRNA bands, suggesting the possible expression of several alternatively spliced products. Occludin mRNA was detected in cultured epithelial cells, but not in cultured fibroblasts. The mRNA level was high in the testis, kidney, liver, lung, and brain, which reportedly bear well-developed tight junctions. We then produced monoclonal and polyclonal antibodies using recombinant mouse occludin as the antigen, which reacted not only with mouse, but also human, dog and pig occludin. These antibodies recognized several bands around 60 kDa in epithelial cells but not in fibroblasts. Immunofluorescence microscopy of various tissues revealed that the staining intensity of occludin correlated well with the number of tight junction strands in epithelial cells. By contrast, the staining of ZO-1, a well-characterized tight junction-associated protein, was not specific for tight junctions. Furthermore, the exclusive concentration of occludin at tight junctions in epithelial cells was confirmed by immunoreplica electron microscopy.

Animals↗
PubMed1997

Detection of numerical and structural alterations and fusion of chromosomes 16 and 1 in low-grade papillary breast carcinoma by fluorescence in situ hybridization.

Intracystic papillary breast tumors, including intraductal papilloma and low-grade intracystic papillary carcinoma, constitute a group for which differential diagnosis is frequently difficult. We examined the status of chromosomes 16 and 1 by multicolor fluorescence in situ hybridization (FISH) analyses and the DNA ploidy patterns by flow cytometry in 26 intracystic papillary tumors. Alterations of chromosomes 16 and 1 were detected by FISH in 93 and 85%, respectively, of 14 low-grade papillary carcinomas, and the latter alterations always concurred with the former. Two-color FISH using probes for the D1Z1 (1q12) and D16Z2 (16cen) loci or the D1Z1 and D16Z3 (16q11) loci showed that fusion of chromosomes 16 and 1, mostly with breakpoints distal to 16q11.2 and proximal to 1q12, occurred in 77% of the papillary carcinomas. DNA aneuploidy was detected in 6% of these carcinomas. No papilloma showed these chromosome alterations or DNA aneuploidy. Chromosome 16 and 1 fusions appeared to occur frequently in diploid breast carcinomas and to be involved in the acquisition of a malignant phenotype by duct epithelial cells. We suggest that two-color FISH methods for detecting 1;16 fusions might be applicable as supportive methods for the differential diagnosis of intracystic papillary breast tumors.

Artificial Gene Fusion↗
PubMed1997

An expression profile of genes in human retina and isolation of a complementary DNA for a novel rod photoreceptor protein.

PURPOSE: To characterize expression patterns of active genes in human retina, and to isolate novel genes that are uniquely expressed in this tissue. METHODS: A 3'-directed complementary DNA (cDNA) library that faithfully represents the composition of messenger RNA (mRNA) was constructed with an mRNA preparation from a cadaveric human retina. A total of 925 3' terminal sequences were collected by sequencing randomly selected clones, of which 789 were regarded as representing chromosomally coded genes (gene signatures [GS]). GS were compared with each other and searched against GenBank. The resulting expression profile, listing gene species and their frequency, represents the composition of mRNA in the retina. By comparing this expression profile with those obtained from 10 other source cells or tissues, genes uniquely active in the retina were discovered, including some not previously described. A full-sized cDNA corresponding to one of these was isolated and sequenced. Its expression was analyzed by multitissue Northern hybridization and in situ hybridization to the retina specimen. It was then mapped on human chromosomes. RESULTS: In the expression profile, 108 genes were detected recurrently, suggesting that they are very active. Fifty-five of them were identified in GenBank, including the most abundant opsin gene and several other genes for phototransduction. Among the remaining novel and active genes, 19 were considered unique to retina on the basis of their representation status in other expression profiles and in dbEST. One of these was identified as a gene that encodes a novel secretory protein expressed in a rod photoreceptor that maps to chromosome 18p11.3. CONCLUSIONS: The expression profile of active genes in the retina represents the composition of mRNA, which reflects the relative activities of genes in this tissue. A comparison of this expression profile with those obtained with other tissues resulted in isolation of a novel cDNA specifically expressed in the rod photoreceptor. It is anticipated that additional novel genes that are uniquely active in the neural retina may be obtained with the same strategy, leading to further clarification of the biologic or physiological characteristics of this tissue.

Amino Acid Sequence↗
PubMed1997

[A case of invasive renal pelvic cancer: usefulness of auxiliary diagnosis using fluorescence in situ hybridization].

A 65-year-old man, on whom transurethral resection had been performed twice for bladder cancer in the past, was admitted to our hospital for further Class V urinary cytology examination. A low density area of 1.5 cm in diameter in the left renal pelvis without enhancement was the only abnormal sign on computed tomographic (CT) imaging. Malignant cells were not detected by random biopsy of the urinary bladder. The retrograde pyelogram showed no filling defect on the left renal pelvis or ureter. The cytological diagnosis of the right split renal urine was Class III, and that of the left split renal urine was Class V. Fluorescence in situ hybridization (FISH) analysis, using specific probes for chromosome 8q21.3 and the centromere chromosome 11, was performed on cells from the bilateral split renal urine. Cells collected from the right split renal urine showed a normal disomic pattern, while those from the left split renal urine included an aneusomic pattern with polysomy. Left total nephroureterectomy was carried out. Histopathology proved invasive renal pelvic cancer. Thus FISH analysis may be useful for the localization of renal pelvic or ureteral cancers, which are difficult to diagnose.

Aged↗
PubMed1996

Breakpoint junction of interstitial homozygous deletion at chromosome 2q33 in a small cell lung carcinoma.

We have characterized the breakpoint junction of the homozygous deletion at chromosome 2q33 in a small cell lung carcinoma cell line. Cloning and sequencing of the genomic regions surrounding the breakpoint junction of the deletion revealed that the homozygous deletion was caused by a simple interstitial deletion of a 220-kb segment. An AT-dinucleotide of contributing germline sequences was overlapped at the junction. Since there were one or two nucleotide overlaps of germline sequences at breakpoint junctions in all four cases of interstitial deletions analyzed to date, this may reflect a common mechanism underlying the occurrence of chromosomal interstitial deletion.

Base Sequence↗
PubMed1996

Molecular cloning of a human RP105 homologue and chromosomal localization of the mouse and human RP105 genes (Ly64 and LY64).

RP105 is a mouse B cell surface molecule that transmits a growth-promoting signal and is implicated in the life/death decision of B cells. RP105 has tandem repeats of a leucine-rich motif in the extracellular domain that is expected to be involved in protein-protein interactions. In the present study, a cDNA clone encoding the human homologue of RP105 was isolated. The amino acid sequence of human RP105 is highly homologous to that of mouse RP105 with 74% identity, and the leucine-rich repeats are well conserved. The expression of the human RP105 transcript was detected in some B cell lines, a histiocytic leukemia cell line, and peripheral blood leukocytes. We also determined the chromosomal locations of the mouse RP105 gene (Ly64 locus) and the human RP105 gene (LY64 locus). Interspecific mouse backcross analysis was used to map the Ly64 locus at the distal region of chromosome 13. The human LY64 locus was localized to 5q12 by fluorescence in situ hybridization, confirming the syntenic relationship between these regions of the mouse and human chromosomes.

Amino Acid Sequence↗
PubMed1996

Subcellular localization and protein interaction of the human LIMK2 gene expressing alternative transcripts with tissue-specific regulation.

In our efforts to explore possible roles of proteins with a LIM domain, which is a cysteine-rich Zinc-binding motif, in differentiation and oncogenesis in the lung, we have cloned a human LIMK2 gene and identified two alternative transcripts, LIMK2a and LIMK2b, which are probably due to variation in transcriptional initiation. The former encodes a protein containing two LIM domains, a PDZ domain, and a kinase domain, while the latter has only one and half LIM domains. The predominance of the two transcripts appears to be regulated in a tissue-specific manner. Alteration of the regulation is also observed in some cancer cell lines. Transfection studies have shown an association of 63-kDa and 58-kDa proteins with the LIMK2a and LIMK2b protein; the former is distributed in the cytoplasm and nucleus and the latter occurs mainly in the cytoplasm and is scarcely translocated to the nucleus. In contrast, a truncated LIMK2-Kinase has a nuclear location, not showing the protein association.

Alternative Splicing↗
PubMed1996

Isolation and characterization of a novel secretory protein, stromal cell-derived factor-2 (SDF-2) using the signal sequence trap method.

With use of the signal sequence trap method, we isolated a cDNA encoding a novel secretory protein, SDF-2, from the mouse stromal cell line, ST2. The human homologue of SDF-2 was also isolated. The amino acid (aa) sequences deduced from both the clones were conserved more than 92%. The chromosomal localization of the human SDF-2 gene was mapped to 17q11.2. The aa sequence of SDF-2 shows similarity to those of yeast dolichyl phosphate-D-mannose:protein mannosyltransferases, Pmt1p [Strahl-Bolsinger et al. (1993) Proc. Natl. Acad. Sci. USA 90, 8164-8168] and Pmt2p [Lussier et al. (1995) J. Biol. Chem. 270, 2770-2775], whose activities have not been detected in higher eukaryotes.

Amino Acid Sequence↗
PubMed1996

Cloning of cDNAs encoding the human BAG1 protein and localization of the human BAG1 gene to chromosome 9p12.

cDNAs encoding the human homolog of BAG1, a Bcl-2-binding protein with anti-apoptotic function, were cloned. DNA sequence analysis of human BAG1 cDNAs predicts a protein with an additional 55 amino acids at its NH2-terminus compared to the mouse protein. Immunoblot assays using monoclonal antibodies raised against bacterially produced h-BAG1 protein confirmed the larger size of the human protein (approximately 34 kDa) compared to mouse. PCR analysis of DNA from human x rodent somatic cell hybrids using human BAG1-specific primers localized the gene to human chromosome 9. Cosmid clones of h-BAG1 were obtained and used for fluorescence in situ hybridization analysis of normal metaphase chromosomes, thus localizing h-BAG1 to 9p12, a region associated with hereditary disorders that may involve developmental dysregulation of programmed cell death.

Amino Acid Sequence↗
PubMed1996

Structurally altered Evi-1 protein generated in the 3q21q26 syndrome.

Overexpression of the Evi-1 gene appears to be a consistent feature of the 3q21q26 syndrome, an association of myeloid leukemias/myelodysplastic syndrome with a specific chromosomal aberration involving both 3q21 and 3q26, such as t(3;3)(q21;q26) or inv(3)(q21q26). The rearrangement in 3q26 has been reported to occur near the Evi-1 locus, implicating that it is the critical gene deregulated in the 3q21q26 syndrome. Here we present a structural abnormality of Evi-1 protein in a case with the 3q21q26 syndrome. In this case carrying typical inv(3)(q21q26), the 3q26 breakpoint is located within an intron of the Evi-1 gene, and resulted in overexpression of normally unexpressed, an aberrant form of Evi-1 protein, in which the C-terminal 44 amino acids of wild-type Evi-1 protein were truncated and replaced by five amino acids. The truncated Evi-1 protein is shown to increase AP1 activity when expressed in NIH3T3 cells as its wild-type counterpart. We also show that the origin of this peculiar type of rearrangement of the Evi-1 gene is not an artifact during establishment of the cell line, but is the event that occurred in the primary leukemic cells. Our results strongly support that the primary target for the 3q21q26 syndrome is the Evi-1 gene, and provide the first evidence that the structurally altered Evi-1 gene may be involved in the 3q21q26 syndrome.

3T3 Cells↗