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J Kusuda

Publications and source records attributed to J Kusuda.

At least 19 recordsLinked to original sources
PubMed1999

Genomic structure and chromosome location of RPL27A/Rpl27a, the genes encoding human and mouse ribosomal protein L27A.

The intron-containing genes encoding human and mouse ribosomal protein (r-protein) L27A were cloned and sequenced. The human r-protein L27A gene (RPL27A) shared an identical exon/intron structure with the mouse r-protein 27A gene (Rpl27a). The translational start codon ATG was separated from the main reading frame by the first intron sequence in both genes. An approximately 200-bp sequence upstream of the translational start site of both genes displayed remarkable similarity, and contained the putative promoters lacking canonical TATA, but harbored Sp1 binding sites and a short stretch of pyrimidine cluster, similar to other r-protein genes. Transcriptional regulatory elements, Box-A and GABP, found in the promoters of some other r-protein genes were also conserved in both genes. These structural features were included in the typical CpG island identified in the 5'-end sequences, suggesting that RPL27A/Rpl27a cloned here are authentic and transcriptionally active. Fluorescence in situ hybridization (FISH) analysis localized the mouse intron-containing Rpl27a to chromosome 7E2-F1 syntenic to human chromosome 11p15, where human RPL27A was located.

Animals↗
PubMed1998

Cloning and chromosomal localization of a paralog and a mouse homolog of the human transaldolase gene.

A sequence homologous to the transaldolase gene (TALDO) was identified in a polymorphic cosmid DNA mapped on human chromosome 11p15 by exon trapping with pSPL3. Analysis of lambda clones contiguous to the cosmid clone showed that the related gene (TALDOR) consists of 8 exons spanning approximately 19kb from the translation start site to the polyadenylation signal. The exon sequence of TALDOR was almost identical with that of TALDO localized on 1p33-34. 1, but its exons corresponding to exons 4 and 5 of TALDO were found to be split by 4 introns in TALDOR. To examine the evolutionary conservation of two genes for transaldolase, we have isolated the cDNA for its mouse homolog and determined the nucleotide sequence covering the complete coding region. Fluorescence in situ hybridization using the cDNA as a probe showed that the mouse transaldolase gene (Taldo) is localized on chromosome 7 F3-F4 as a single copy gene. This chromosomal region is known to be syntenic to human chromosome 11p15 rather than to 1p33-p34.1, suggesting that TALDOR is the ancestral form. The existence of TALDOR implies a duplication of the mammalian transaldolase gene after divergence of rodent and primate.

Amino Acid Sequence↗
PubMed1997

Cloning and chromosomal mapping of human casein kinase I gamma 2 (CSNK1G2).

A clone of immature cDNA for human casein kinase I gamma 2 (CSNK1G2) was isolated by screening the human testis cDNA library with a PCR-amplified probe (about 400 bp) representing the kinase domain of rat casein kinase I gamma 2 (CKI gamma 2). Comparison of the entire sequence with that of rat CKI gamma 2 showed that the cDNA contained the complete coding sequence of CKI gamma 2 as well as an intron-like sequence of 1006 bp, part of which was homologous to the Alu sequence. To obtain an insertion-free CSNK1G2 cDNA, PCR cloning was performed based on the above sequence. The amplified 1687-bp fragment was subcloned and sequenced. The predicted amino acid sequence consisted of 416 residues, 94% of which were identical to that of the rat homologue. Although there are two Src homology 3 (SH3) domain-binding motifs (Pro-X-X-Pro consensus), Pro-Lys-Val-Pro and Pro-Ser-Glu-Pro in the C-terminal region of rat CKI gamma 2, only the latter was conserved in the human counterpart. This finding suggests that the latter motif is important for binding to the signal transduction adaptor protein Nck (NCK). The human CSNK1G2 gene was mapped to chromosome 19p13.3 by fluorescence in situ hybridization and PCR analysis of the human/rodent hybrid cell panel.

Amino Acid Sequence↗
PubMed1997

Molecular cloning of a novel human CC chemokine secondary lymphoid-tissue chemokine that is a potent chemoattractant for lymphocytes and mapped to chromosome 9p13.

By searching the Expressed Sequence Tag (EST) data base, we identified partial cDNA sequences potentially encoding a novel human CC chemokine. We determined the entire cDNA sequence which encodes a highly basic polypeptide of 134 amino acids total with a putative signal peptide of 23 amino acids. The predicted mature protein of 111 amino acids has the four canonical cysteine residues and shows 21-33% identity to other human CC chemokines, but has a unique carboxyl-terminal extension of about 30 amino acids which contains two extra cysteine residues. The mRNA was expressed strongly in tissues such as the lymph nodes, Appendix, and spleen. The recombinant protein, which was produced by the baculovirus system and purified to homogeneity, was a highly efficient chemoattractant for certain human T cell lines and a highly potent one for freshly isolated peripheral blood lymphocytes and cultured normal T cells expanded by phytohemagglutinin and interleukin 2. Unlike most other CC chemokines, however, this novel chemokine was not chemotactic for monocytes or neutrophils, suggesting that it is specific for lymphocytes. From these results, we designated this novel CC chemokine as SLC from secondary lymphoid-tissue chemokine. SLC fused with the secreted form of alkaline phosphatase (SLC-SEAP) was used to characterize the SLC receptor. Binding of SLC-SEAP to freshly isolated lymphocytes was blocked by SLC (IC50, 0.12 nM) but not by any other CC chemokine so far tested, suggesting that resting lymphocytes express a class of receptors highly specific for SLC. By using somatic cell hybrids, radiation hybrids, and selected yeast and bacterial artificial chromosome clones, we mapped the SLC gene (SCYA21) at chromosome 9p13 and between chromosomal markers, D9S1978(WI-8765) and AFM326vd1, where the gene for another novel CC chemokine termed ELC from EBI1-ligand chemokine (SCYA19) also exists. Collectively, SLC is a novel CC chemokine specific for lymphocytes and, together with ELC, constitutes a new group of chemokines localized at chromosome 9p13.

Amino Acid Sequence↗
PubMed1997

Molecular cloning of a novel human CC chemokine EBI1-ligand chemokine that is a specific functional ligand for EBI1, CCR7.

By searching the expressed sequence tag (EST) data base, we identified partial cDNA sequences encoding a novel human CC chemokine. We determined the complete cDNA sequence that encodes a highly basic polypeptide of a total 98 amino acids with 20 to 30% identity to other human CC chemokines. We termed this novel chemokine from EBI1-Ligand Chemokine as ELC (see below). The ELC mRNA was most strongly expressed in the thymus and lymph nodes. Recombinant ELC protein was expressed as a fusion protein with the Flag tag (ELC-Flag). For receptor-binding assays, recombinant ELC protein fused with the secreted form of alkaline phosphatase (SEAP) was used. By stably expressing five CC chemokine receptors (CCR1 to 5) and five orphan receptors, ELC-SEAP was found to bind specifically to an orphan receptor EBI1. Only ELC-Flag, but not MCP-1, MCP-2, MCP-3, eotaxin, MIP-1alpha, MIP-1beta, RANTES (regulated on activation normal T cell expressed and secreted), thymus and activation-regulated chemokine (TARC), or liver and activation-regulated chemokine (LARC), competed with ELC-SEAP for EBI1. ELC-Flag-induced transient calcium mobilization and chemotactic responses in EBI1-transfected cells. ELC-Flag also induced chemotaxis in HUT78 cells expressing endogenous EBI1 at high levels. By somatic hybrid and radiation hybrid analyses, the gene for ELC (SCYA19) was mapped to chromosome 9p13 instead of chromosome 17q11.2 where the genes for CC chemokines are clustered. Taken together, ELC is a highly specific ligand for EBI1, which is known to be expressed in activated B and T lymphocytes and strongly up-regulated in B cells infected with Epstein-Barr virus and T cells infected with herpesvirus 6 or 7. ELC and EBI1 may thus play roles in migration and homing of normal lymphocytes, as well as in pathophysiology of lymphocytes infected with these herpesviruses. We propose EBI1 to be designated as CCR7.

Amino Acid Sequence↗
PubMed1997

Molecular cloning of a novel human CC chemokine liver and activation-regulated chemokine (LARC) expressed in liver. Chemotactic activity for lymphocytes and gene localization on chromosome 2.

Partial overlapping cDNA sequences likely to encode a novel human CC chemokine were identified from the GenBank Expressed Sequence Tag data base. Using these sequences, we isolated full-length cDNA encoding a protein of 96 amino acid residues with 20-28% identity to other CC chemokines. By Northern blot, this chemokine was mainly expressed in liver among various tissues and strongly induced in several human cell lines by phorbol myristate acetate. We thus designated this chemokine as LARC from Liver and Activation-Regulated Chemokine. We mapped the LARC gene close to the chromosomal marker D2S159 at chromosome 2q33-q37 by somatic cell and radiation hybrid mappings and isolated two yeast artificial chromosome clones containing the LARC gene from this region. To prepare LARC, we subcloned the cDNA into a baculovirus vector and expressed it in insect cells. The secreted protein started at Ala-27 and was significantly chemotactic for lymphocytes. At a concentration of 1 microg/ml, it also showed a weak chemotactic activity for granulocytes. Unlike other CC chemokines, however, LARC was not chemotactic for monocytic THP-1 cells or blood monocytes. LARC tagged with secreted alkaline phosphatase-(His)6 bound specifically to lymphocytes, the binding being competed only by LARC and not by other CC or CXC chemokines. Scatchard analysis revealed a single class of receptors for LARC on lymphocytes with a Kd of 0.4 nM and 2100 sites/cell. Collectively, LARC is a novel CC chemokine, which may represent a new group of CC chemokines localized on chromosome 2.

Amino Acid Sequence↗
PubMed1996

Isolation and analysis of a novel gene, HXC-26, adjacent to the rab GDP dissociation inhibitor gene located at human chromosome Xq28 region.

We screened potential promoter regions from NotI-linking cosmid clones mapped on human chromosome Xq28 region with our constructed trapping vector and isolated six fragments containing transcription activity. Using one of the obtained fragments as a probe, a novel gene was isolated by screening a human skeletal muscle cDNA library. The isolated cDNA, termed HXC-26, contained an open reading frame of 975 nucleotides encoding 325 amino acids (38,848 Da). The HXC-26 gene was composed of 13 exons that span approximately 8 kb. Several potential GC boxes were found in the putative promoter region, but no typical TATA box. The HXC-26 gene associated with a CpG island was located adjacent to the rab GDP dissociation inhibitor (GDI) gene.

Amino Acid Sequence↗
PubMed1996

Human rasGTPase-activating protein (human counterpart of GAP1m): sequence of the cDNA, primary structure of the protein, production and chromosomal localization.

When cDNA encoding rat rasGTPase-activating protein (rat GAP1m) was used as a probe, two partial cDNA clones of a human counterpart of rat GAP1m were isolated from a cDNA library derived from growth-arrested normal human ectocervical epithelial cells. One clone was found to be a cDNA of premature mRNA with two introns. A complete cDNA of human GAP1m was constructed by a series of reverse transcription-polymerase chain reaction (RT-PCR) using total RNA from human epidermoid carcinoma A431 cells. Human GAP1m shows 87.7% nucleotide identity to rat GAP1m in open reading frame and encodes an 850-amino acid protein that shows 89.2% identity to rat GAP1m. A 100-kDa protein was detected in A431 cells by Western blotting with anti-rat GAP1m antibody. The human GAP1m gene was mapped to chromosome 3q24-q26.

Animals↗
PubMed1996

Identification of the gene-richest bands in human chromosomes.

The human genome is a mosaic of isochores, long DNA segments which are compositionally homogeneous and which can be partitioned into five families, L1, L2, H1, H2 and H3, characterized by increasing GC levels and by increasing gene concentrations. Previous investigations showed that in situ hybridization with a DNA fraction derived from the GC-richest and gene-richest isochores of the H3 family produced the highest concentration of signals on 25 R(everse) bands that include the 22 most thermal-denaturation-resistant T(elomeric) bands, a subset of R bands. Using an improved protocol for in situ hybridization and cloned H3 isochore DNA, we have now shown (i) that the number of bands which are characterized by strong hybridization signals, and which are here called T or H3+, is 28; (ii) that 31 additional R bands, here called T'or H3* bands, also contain H3 isochores, although at a lower concentration than H3+ bands; and (iii) that the remaining R bands (about 140 out of 200, at a resolution of 400 bands), here called R" or H3- bands, do not contain any detectable H3 isochores. H3+ and H3* bands contain all the gene-richest isochores of the human genome. The existence of three distinct sets of R bands is further supported (i) by the different compositional features of genes located in them; (ii) by the very low gene density of chromosomes 13 and 18, in which all R bands are H3- bands; (iii) by the compositional map of a H3* band, Xq28; (iv) by the overwhelming presence of GC-rich and GC-poor long (> 50 kb) DNA sequences in H3+/H3* and in H3-/G bands, respectively; and (v) by the large degree of coincidence of H3+ and H3* bands with CpG island-positive bands. These observations have implications for our understanding of the causes of chromosome banding and provide a classification of chromosomal bands that is related to GC level (and to gene concentration).

Chromosome Banding↗
PubMed1996

Sequence analysis of the cDNA for the human casein kinase I delta (CSNK1D) gene and its chromosomal localization.

A cDNA clone coding for human casein kinase I (CK1) has been isolated and sequenced. The insert of 1911 bp contained an open reading frame of 415 amino acids. The entire amino acid sequence of human CK1 was 97% homologous to that of rat CK1 delta, and their sequences in the kinase domain (284 amino acid residues) were completely identical, predicting that the obtained cDNA is for a human homolog of the CK1 delta isoform (CSNKID). The considerable similarity in the amino acid sequence of the kinase domain of human CK1 delta to the Saccharomyces cerevisiae CK1, HRR25 (66%), and to the Saccharomyces pombe CK1, HHP1 (78%), which are involved in the repair of DNA strand break, supports the speculation that human CK1 delta might also act in DNA metabolism through excision and recombinational repair. The human CK1 delta gene was mapped to chromosome 17q25.2-q25.3 by fluorescence in situ hybridization and polymerase chain reaction analysis of the human/rodent hybrid cell panels.

Amino Acid Sequence↗
PubMed1996

Primary culture of chicken hepatocytes in serum-free medium (pH 7.8) secreted albumin and transferrin for a long period in free gas exchange with atmosphere.

To study liver functions of chicken, we examined the primary culture of chicken hepatocytes, and found an easy method of long-term culture with free atmosphere exchange. Chicken hepatocytes were obtained by collagenase perfusion and cultured at 37 degrees C as a monolayer without substratum in serum-free L-15 medium (pH 7.8) with free atmosphere exchange. The amounts of albumin and transferrin in medium were assayed by ELISA. The culture of chicken hepatocytes was maintained in the serum-free L15-medium )pH 7.) and 37 degrees C with free atmosphere exchange for 20 days. The amount of albumin secreted in the medium decreased to low levels early in culture; however, this was followed by marked increase from day 9 to day 17 of culture. The amount of transferrin was constant until day 6, then it too increased with further culture. We reported an easy method for the simple monolayer culture of chicken hepatocytes in serum-free L12 medium (pH 7.8) with free atmosphere exchange over an extended period. Expression of liver-specific functions, viz. albumin and transferrin synthesis, was observed after 1 week of culture.

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