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Biomedical subjects

S Ohno

Publications and source records attributed to S Ohno.

At least 883 records · Page 49Linked to original sources
PubMed1983

The 5'-flanking sequence of human interferon-beta 1 gene is responsible for viral induction of transcription.

The structural gene for Herpes simplex virus (HSV) thymidine kinase (Tk) was fused downstream of the 5'-flanking sequence (from -284 to +20; numbering relative to the putative transcription initiation site) of the cloned human interferon-beta 1 (IFN-beta 1) gene. The fusion gene was linked to the vector pSV2-Ecogpt and the recombinant plasmid was used to transform mouse FM3A cells. All cloned transformants in which the fusion gene was integrated in an intact form produced the Tk specific transcript with the distinct 5' terminus corresponding to that of the authentic IFN-beta 1 mRNA when they were exposed to Newcastle disease virus (NDV). Thus, the results reported here provide evidence for the presence of specific DNA sequences in the 5'-flanking region of the IFN-beta 1 gene required for the virus mediated activation of transcription.

Animals↗
PubMed1983

Structure and expression of a cloned cDNA for mouse interferon-beta.

A unique sequence in the mouse genome which cross-hybridized to a cloned human interferon-beta 1 gene was detected by DNA blot analysis. Taking advantage of this, a cDNA library prepared from partially purified mRNA for mouse interferon-beta was screened using human interferon-beta 1 DNA as a probe. One of the positive clones, pM beta-3, contained a 680-base pair cDNA insert, whose base sequence contained a single large open reading frame for 182 amino acids. The coding sequences of the cDNA showed homologies of 63% at the nucleotide and 48% at the amino acid level with respect to human interferon-beta 1 cDNA (Taniguchi, T., Ohno, S., Fujii-Kuriyama, Y., and Muramatsu, M. (1980) Gene 10, 11-15). The first 21 amino acids, considered to be the signal peptide, were followed by 24 amino acids, whose sequence was identical with the NH2-terminal sequence that had been reported for mouse interferon-beta from Ehrlich ascites tumor cells (Taira, H., Broeze, R. J., Jayaram, B. M., Lengyel, P., Hunkapiller, M. W., and Hood, L. E. (1980) Science (Wash. D.C.) 207, 528-530). The complete primary sequence of mature interferon-beta polypeptide consisting of 161 amino acids (Mr = 19,700) was deduced. There are three N-glycosylation sites, and this offers an explanation for the larger molecular size (Mr = 26,000-40,000) of natural mouse interferon-beta in comparison to the deduced interferon polypeptide. The cDNA, when fused to a SV40 promoter sequence and then introduced into COS-7 cells, directed the synthesis and secretion of a protein product indistinguishable from the authentic mouse interferon-beta.

Amino Acid Sequence↗
PubMed1983

Interactions of nuclear estrogen receptor with DNA and RNA.

The interaction of the nuclear estrogen receptor from hen oviduct with nucleic acids were studied by competition assay using DNa-cellulose centrifugation. We demonstrated that the estradiol-receptor complex binds similarly well to poly(A) RNA and denatured DNA. The estrogen receptor was found to interact more strongly with poly(G), poly(U) than with poly(A), poly(C). The receptor complex binds similarly to poly(A) and poly(dA), and to poly(U) and poly(dU). However, the receptor complex shows stronger binding to poly(G) than to poly(dG) and to poly(C) than to poly(dC). Studies with heteropolyribonucleotides indicated that poly(U1G1) is more effective in competing for the estrogen receptor, and poly(AC) and poly(AUG) are moderately effective, whereas poly(ACU) is least effective. GMP and dGMP showed some competition for the nuclear receptor at 300-fold higher nucleotide concentrations than that of the synthetic poly(G). Observations that the nuclear estrogen receptor binds to poly(A) RNA and interacts selectively with polyribonucleotides suggest that the estrogen receptor-RNA interaction may play a role for the function of estrogens in gene regulation.

Animals↗
PubMed1983

[Role of the ventrolateral part of the medulla oblongata in the control of gonadotropin secretion. I. Electrophysiological studies on the neural features between the limbic-preoptic structures and the ventrolateral part of the medulla oblongata in the female rat].

Electrophysiological studies were undertaken in order to investigate the neural features between the preoptic suprachiasmatic nucleus (POSC) and the ventrolateral part of the medulla oblongata (VLMO) and between the bed nucleus of stria terminalis (BST) and VLMO by eliciting antidromic responses and performing microionophoresis of estradiol. Unit activity of neurons in the VLMO was recorded in ovariectomized estradiol benzoate-primed Wistar female rats under urethane anesthesia (1.2g/kg body weight). Antidromic activations were performed by applying negative square wave pulses (intensity 1.0--1.5mA, duration 0.1msec, frequency 0.6Hz) which were delivered through a bipolar concentric stainless steel electrode to the POSC or the BST. In total, 116 neurons in the POSC and 118 neurons in the BST with ascending projection were identified in the VLMO. Both in the POSC and the BST, two types of antidromic spike potentials were distinguished on the basis of their waveforms. One type ("fast spikes") was characterized by a sharp and smooth rising phase. The other ("slow spikes") had a notch in the rising phase. In the POSC, mean antidromic spike latency for the fast spikes was 9.8msec, while the value for the slow spikes was 30.4msec and in the BST, mean antidromic spike latency for the fast spikes was 10.2msec, while the value for the slow spikes was 31.5msec. In the POSC, ionophoretic injection of estradiol hemisuccinate was accomplished on 57 of the 116 antidromically identified cells, of which 32 showed slow responses and 25 responded with fast spikes. In cells with slow spikes, estradiol hemisuccinate facilitated (n = 14) or suppressed (n = 5) their generation of action potentials. None of the cells with fast responses changed their activity in response to estradiol hemisuccinate. In the BST, ionophoretic injection of estradiol hemisuccinate was accomplished on 51 of 118 antidromically identified cells, of which 30 showed slow responses and 21 responded with fast spikes. In cells with slow spikes, estradiol hemisuccinate facilitated (n = 9) or suppressed (n = 8) their generation of action potentials. None of the cells with fast responses changed their activity in response to estradiol hemisuccinate. In addition, POSC or BST unit responses to the VLMO stimulation (intensity 1.0--1.5mA, duration 0.1msec, frequency 0.6Hz) was examined. Unit firing activity in the POSC or BST, elicited by the VLMO stimulation, was much more enhanced in proestrous rats than in diestrous rats. After the injection of phenoxybenzamine, an alpha-adrenergic receptor blocker, the rate of facilitatory responses in the POSC or in the BST neurons was significantly decreased in proestrous rats.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1983

[The role of the ventrolateral part of the medulla oblongata in the control of gonadotropin secretion. II. The effect of ovarian steroid implantation into the ventrolateral part of the medulla oblongata on LH secretion in the female rat].

To investigate whether neurons in the ventrolateral part of the medulla oblongata (VLMO) are sensitive to ovarian steroid, estradiol benzoate (EB) or progesterone (Prog.) was implanted through a stainless steel double cannula into the VLMO of ovariectomized, EB-primed rats and serum LH was measured. Two weeks after ovariectomy, rats were primed with 20 micrograms EB at 1200h and this day was arbitrarily defined as day 0. At 1200h on day 3, powdery steroid, EB or Prog., was unilaterally implanted into the VLMO. Implantation of EB into the VLMO was effective in increasing serum LH at 1600, 1800 and 2000h on days 3 and 4, but the serum LH concentration at 1600, 1800 and 2000h was much more increased on day 4 than on day 3. Implantation of Prog. into the VLMO failed to induce a significant increase in serum LH on days 3 and 4. To further investigate the effects of anterolateral hypothalamic (ALH) transection and complete spinal transection at T4-T7 levels on EB implantation into the VLMO was examined. It has been shown that both ALH transection and spinal transection at high thoracic levels (T4-T7) significantly blocked proestrous gonadotropin surges and ovulation. In rats with ALH transection, EB implantation into the VLMO was not effective in increasing serum LH at 1600, 1800 and 2000h on days 3 and 4, but in rats with complete spinal transection, EB implantation into the VLMO was effective in increasing serum LH at 1800 and 2000h on days 3 and 4. These results suggest that EB exerts its stimulatory feedback action on the VLMO and the anterolateral hypothalamic area is involved in the mechanism of this stimulatory feedback action of EB.

Animals↗
PubMed1983

On evolutionarily conserved simple repetitive DNA sequences: do "sex-specific" satellite components serve any sequence dependent function?

The nuclear genomes of eukaryotes contain DNA of varying degrees of repetition. Highly repetitious DNA and simple repetitive sequences as a fraction thereof appear to be distributed in a non-random fashion in the genome. There are arguments for and against functional roles of simple repetitive sequences, and the reasons for their evolutionary conservation are not at all clear. In order to learn more about the biologic role of simple repetitive sequences in the context of their evolutionary history, we report here the following results from studies of sex-specific snake satellite DNA: 1) The snake simple repeat sequence is 5'-GATAGACA-3' and it is strictly conserved throughout vertebrate evolution. 2) The simple repeat sequence is intimately interspersed with single-copy DNA throughout the mouse genome. 3) The simple repeat is transcribed into RNA in several animal systems and it is translatable in bacterial test systems. 4) The simple repeat sequence is sex-specifically arranged in vertebrates. 5) In snake DNA, the simple repeat is adjacent to a single-copy sequence which singles out a male-specific putative mRNA in mouse polysomal poly (A)+ RNA. Thus even if this snake simple repetitive sequence is not involved in a basic cellular function such as sex-determination, it is nevertheless a valuable tool to approach those problems.

Animals↗
PubMed1983

The primitive code and repeats of base oligomers as the primordial protein-encoding sequence.

Even if the prebiotic self-replication of nucleic acids and the subsequent emergence of primitive, enzyme-independent tRNAs are accepted as plausible, the origin of life by spontaneous generation still appears improbable. This is because the just-emerged primitive translational machinery had to cope with base sequences that were not preselected for their coding potentials. Particularly if the primitive mitochondria-like code with four chain-terminating base triplets preceded the universal code, the translation of long, randomly generated, base sequences at this critical stage would have merely resulted in the production of short oligopeptides instead of long polypeptide chains. We present the base sequence of a mouse transcript containing tetranucleotide repeats conserved during evolution. Even if translated in accordance with the primitive mitochondria-like code, this transcript in its three reading frames can yield 245-, 246-, and 251-residue-long tetrapeptidic periodical polypeptides that are already acquiring longer periodicities. We contend that the first set of base sequences translated at the beginning of life were such oligonucleotide repeats. By quickly acquiring longer periodicities, their products must have soon gained characteristic secondary structures--alpha-helical or beta-sheet or both.

Amino Acid Sequence↗
PubMed1983

Recurrence of 49-base decamers, nonomers, and octamers within mouse C mu gene of Ig heavy chain and its primordial building block.

Within the published 2,168-base-long mouse C mu gene of Ig heavy chain consisting of four coding and four noncoding segments, 2 base decamers, 8 nonomers, and 39 octamers recurred. Recurring base heptamers (about 100) and hexamers (about 350) were simply too numerous to merit individual identification. In spite of extensive overlaps between these recurring base decamers to hexamers, they occupied nearly the entire length of mouse Ig C mu gene. As with other genes of the beta-sheet-forming beta 2-microglobulin family, the Ig C mu gene (flanking and intervening noncoding sequences included) is not a unique sequence but rather it is degenerate repeats of the 45-base-long primordial building-block sequence uniquely its own. This primordial building block must originally have specified the 15-amino-acid-residue-long primordial arm of beta-sheet-forming loops, the characteristics of the beta 2-microglobulin family of polypeptides.

Amino Acid Sequence↗
PubMed1983

Homology between coding and noncoding sequences within the human class I HLA antigen gene.

In our previous paper, we identified 32 recurring base oligomers (1 decamer, 4 octamers, 9 heptamers and 18 hexamers) within the coding sequence for the mouse class I major histocompatibility (MHC) antigen H-2Kb. The compilation of these recurring base oligomers led to the conclusion that the entire ancestral coding sequence for class 1 MHC antigens evolved from tandem repeats of the one 45 base-long primordial building block base sequence. As with most other mammalian genes, the gene for each class I MHC antigen is an admixture of coding and noncoding segments interspersed with each other. Thus, the status of noncoding segments should be clarified in relation to the concept of the primordial building block. The published 4,122 base-long sequence of human pHLA 12.4 germline gene afforded me an opportunity for clarification. Since the number of recurring base oligomers residing within the entire 4,000 + base-long sequence proved unmanageably numerous, the two portions 1,200 bases in the total length were singled out. Within these portions containing five noncoding and four coding segments, noncoding and coding segments shared 1 nonomer, 3 octamers, 6 heptamers and 5 hexamers; all the above-noted base oligomers were derived from different parts of the same 45 base-long primordial building block. It was thus concluded that not only the coding segments, but the entire ancestral gene for class I MHC antigens evolved from tandem repeats of the 45-base-long primordial building block. This new concept of primordial building block was discussed in relation to the mechanism of evolution by gene duplication.

Base Sequence↗
PubMed1983

The effect of K-582, a new antifungal agent, on experimental Candida keratitis.

K-582, a new basic peptide antibiotic, was tested in rabbits with experimental Candida keratitis. It was shown that the K-582-treated group showed statistically highly significant therapeutic effects on days 2 and 3, as compared with the control group (day 2: P less than 0.001; day 3: P less than 0.001). The culture study showed that the average number of colonies was 1,573.1 in the controls and 463.3 in the treated group, and the difference was highly significant statistically (P less than 0.001). No ocular or systemic toxic effects were observed with this drug. K-582 is a promising new drug for the treatment of Candida keratitis.

Animals↗
PubMed1983

Spontaneous production of gamma-interferon in cultures of T lymphocytes obtained from patients with Behçet's disease.

The spontaneous production of interferon (IFN) in the cultures of peripheral blood mononuclear leukocytes (PBML) obtained from 30 patients with Behçet's disease was investigated. PBML obtained from each of 26 patients in the convalescent stage and four patients in the exacerbation stage were cultured at least twice without stimulation, and IFN activity in the culture fluid 2 to 7 days after the cultivation was assayed. Twenty PBML of normal healthy donors were also cultured simultaneously. PBML of all patients in the convalescent stage spontaneously produced high-titered IFN (60.0 +/- 9.5 IU/ml), but IFN activity produced in PBML cultures of four patients in the exacerbation stage was very low or was undetectable. Similarly, IFN was always detectable in the circulation of the patients whose PBML spontaneously produced IFN. All IFN activity detected both in the circulation and in the fluid of PBML culture from these patients was gamma-IFN, defined by virtue of its acid lability and antigenicity neutralized with antiserum for gamma-IFN and not with antisera for alpha- and beta-IFN. The cellular source of this gamma-IFN in the patients' PMBL was T lymphocytes and not non-T cells or macrophages. T lymphocytes did not require the help of macrophages. It is suggested that T lymphocytes of these patients may be stimulated by unknown causative agents in vivo and may produce gamma-IFN in vivo as well as in in vitro culture of T lymphocytes.

Adult↗
PubMed1983

Case of primary orbital hemangiopericytoma.

A case of primary orbital hemangiopericytoma was reported. A 44-year-old woman was first seen at our clinic in June 1970, complaining of exophthalmos of the right eye. On examination, the right eye showed a 6-mm proptosis and an upward displacement. Cerebral angiography revealed a vascularized mass occupying the lower and mid orbit. The tumor was surgically removed and diagnosed histologically as hemangiopericytoma. After the initial surgery, recurrent tumors in the right orbit were resected twice, in June 1975 and December 1979. The purpose of this presentation is to discuss the clinicopathologic features of the tumor. In addition, it is emphasized that hemangiopericytomas originating from the orbit or brain may be histopathologically identical to angioblastic meningiomas.

Adult↗