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J Kataoka

Publications and source records attributed to J Kataoka.

At least 37 records · Page 2Linked to original sources
PubMed1992

Adenine depurination and inactivation of plant ribosomes by an antiviral protein of Mirabilis jalapa (MAP).

Mirabilis antiviral protein (MAP) is a single-chain ribosome-inactivating protein (RIP) isolated from Mirabilis jalapa L. It depurinates the 28S-like rRNAs of prokaryotes and eukaryotes. A specific modification in the 25S rRNA of M. jalapa was found to occur during isolation of ribosomes by polyacrylamide/agarose composite gel electrophoresis. Primer extension analysis revealed the modification site to be at the adenine residue corresponding to A4324 in rat 28S rRNA. The amount of endogenous MAP seemed to be sufficient to inactivate most of the homologous ribosomes. The adenine of wheat ribosomes was also found to be removed to some extent by an endogenous RIP (tritin). However, the amount of endogenous tritin seemed to be insufficient for quantitative depurination of the homologous ribosomes. Endogenous MAP could shut down the protein synthesis of its own cells when it spreads into the cytoplasm through breaks of the cells. Therefore, we speculate that MAP is a defensive agent to induce viral resistance through the suicide of its own cells.

Adenine↗
PubMed1992

Radioimmunoassay of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol 3-glucuronide in serum of patients with cerebrotendinous xanthomatosis.

A rapid, convenient, and specific radioimmunoassay for 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol has been developed. Specific antiserum was obtained from rabbits immunized by the bile alcohol-bovine serum albumin conjugate, which was coupled by an (O-carboxymethyl)oxime bridge at the C-3 position. The assay produces values for serum concentrations of bile alcohol glucuronides in patients with cerebrotendinous xanthomatosis.

Brain Diseases↗
PubMed1991

Substantial increase of the inhibitory activity of Mirabilis antiviral protein by an elimination of the disulfide bond with genetic engineering.

Mirabilis antiviral protein (MAP) is a rigid, heat-stable protein composed of 250 amino acids with an intramolecular disulfide bond. MAP inhibits the in vitro protein synthesis of rabbit reticulocyte with approximately one-thirtieth the activity of the ricin A chain, a homologous protein with no such bond (Habuka, N., Murakami, Y., Noma, M., Kudo, T., and Horikoshi, K. (1989) J. Biol. Chem. 264, 6629-6637; Habuka, N., Akiyama, K., Tsuge, H., Miyano, M., Matsumoto, T., and Noma, M. (1990) J. Biol. Chem. 265, 10988-10992). The bond is presumed to induce some structural perturbation that alters the mode of interaction with the substrate ribosome and thus lowers the activity. To confirm this hypothesis, a mutant MAP gene in which the codons of both cysteines were replaced by those of serines was constructed and expressed in Escherichia coli, and its product (C36/22OS) was purified. In a sodium dodecyl sulfate-polyacrylamide gel electrophoresis, C36/220S showed the same mobility as that of MAP reduced by 2-mercaptoethanol, whereas nonreduced MAP showed faster migration. The inhibitory activity of C36/220S was approximately 22 times higher than that of native MAP, that is the mutant had an IC50 of 0.16 nM for the protein synthesis of the rabbit reticulocyte system, whereas the native MAP had an IC50 of 3.5 nM. The results indicate that the activity of MAP is increased by the elimination of the disulfide bond, and this supports the hypothesis.

Amino Acid Sequence↗
PubMed1991

Escherichia coli ribosome is inactivated by Mirabilis antiviral protein which cleaves the N-glycosidic bond at A2660 of 23 S ribosomal RNA.

Ribosome-inactivating proteins (RIPs) are known to inactivate eukaryotic ribosomes, which results in the inhibition of protein synthesis, but there has been no evidence that they inactivate the ribosomes of Escherichia coli. Recently, Mirabilis antiviral protein (MAP), a RIP, has been shown to inhibit the protein synthesis of E. coli as well as eukaryotes. To elucidate its mechanism, E. coli ribosomes treated with MAP were analyzed by polyacrylamide/agarose composite gel electrophoresis and RNA sequencing using reverse transcriptase with DNA primer. The 23 S rRNAs, with an A260 value for ribosomes of 15, were completely cleaved in vitro by a 30 minute treatment with MAP at a concentration of 100 nM at 37 degrees C and a subsequent treatment with aniline. However, they were not affected by ricin A-chain under the same conditions. The primer extension of DNA polymerization stopped before A2660 of 23 S rRNA in RNA sequencing. Furthermore, both 16 S and 23 S rRNAs were cleaved by the MAP and aniline treatments when naked E. coli rRNAs were used as substrates, and the primer extension stopped before bases A2660 and A1014, respectively, in RNA sequencing. As the A2660 region has been shown to interact with the elongation factors EF-Tu and EF-G these results indicate that MAP cleaves the N-glycosidic bond at A2660 in E. coli 23 S RNA resulting in the inactivation of the ribosome.

Base Sequence↗
PubMed1991

DNA sequence of Mirabilis antiviral protein (MAP), a ribosome-inactivating protein with an antiviral property, from mirabilis jalapa L. and its expression in Escherichia coli.

We cloned a cDNA for Mirabilis antiviral protein (MAP), a ribosome-inactivating protein (RIP), which inhibits the mechanical transmission of plant virus and the in vitro protein synthesis of both prokaryotes and eukaryotes. The cDNA consisted of 1066 nucleotides and could encode 278 amino acids. The major part of the amino acid sequence (from Ala29 to Ser278) was identical with the sequence of native MAP as determined by protein sequencing. An NH2-terminal extrapeptide (28 amino acid residues) of MAP was comparable with the signal peptides of plant proteins accumulating in the vacuole. A stable hairpin structure was predicted in the 3'-noncoding region of the cDNA. Tandem repeated sequences were found downstream from the hairpin structure. They were composed of triple complete repeats of a heptanucleotide with preceding and following hexa-nucleotide repeats. The cDNA was expressed in Escherichia coli based on the T7 expression system. The product encoded by the cDNA was confirmed to be MAP precursor by Western blotting followed by immunological analysis. The growth of the transformants was inhibited by the expression of the gene. MAP precursor also seemed to inhibit the protein synthesis of E. coli just as native MAP has been observed to do.

Amino Acid Sequence↗
PubMed1991

Functional analysis of deletion mutants of cucumber mosaic virus RNA3 using an in vitro transcription system.

Full-length DNA copies of RNAs 1, 2, and 3 of CMV Y strain (CMV-Y) were cloned downstream of modified phage T7 promoter sequences to obtain infectious RNA transcripts. The small number of extra nonviral nucleotides at the 5' ends considerably decreased the specific infectivity of the transcripts of RNAs 1 and 2 but did not affect that of the RNA3 transcripts. Using the most infective transcripts, up to 45% of tobacco protoplasts could be infected. Various cDNA mutants were constructed from the full-length RNA3 cDNA to give RNA transcripts having deletions in the coding region of the 3a protein or the coat protein. These mutants replicated in tobacco protoplasts but did not produce systemic symptoms on tobacco when inoculated together with transcripts of RNAs 1 and 2. One of the mutants having a small in-frame deletion near the N-terminal region of the coat protein produced local lesions on cowpea and local chlorotic spots on the inoculated leaves of tobacco. These results suggest that both the 3a protein and the coat protein are involved in virus transport, and that viral assembly is associated with long-distance movement of CMV.

Base Sequence↗
PubMed1991

Physicochemical properties of pseudorabies virus hemagglutinin.

Pseudorabies virus hemagglutinin was readily adsorbed on mouse erythrocytes at 4, 22, or 37 degrees C, but not on cattle erythrocytes. The adsorbed hemagglutinin could not be eluted from the cells by resuspending in phosphate-buffered saline (PBS), by incubating at 37 or 50 degrees C, or by incubating in the presence of neuraminidase. The receptor on mouse erythrocytes for the hemagglutinin was inactivated by trypsin, but not by neuraminidase, sodium deoxycholate (DOC), potassium periodate (KIO4), dithiothreitol (DTT), 2-mercaptoethanol (2-ME) and formalin. The hemagglutinin was inactivated by trypsin, alpha-amylase, pepsin, DOC, KIO4, and ethylendiamine-tetraacetic acid (EDTA), but not by papain, beta-glucosidase, phospholipase C, neuraminidase, DTT, 2-ME, Tween-80, ethylether, chloroform, trichloro-trifluoroethane, beta-propiolactone and formalin, suggesting that the hemagglutinin active component involved glycoproteins. The hemagglutinin was stable at 37 degrees C for lower temperatures but not at 60 degrees C or higher. The hemagglutinin activity was resistant to ultraviolet irradiation, while the infectivity was very susceptible. The hemagglutinin and the infectivity were readily sedimented by ultracentrifugation at 48,000 x g for 3 hr. In rate zonal centrifugation of the preparation on a sucrose density gradient, the hemagglutination (HA) activity showed a sharp peak at 1.22 g/ml coinciding with the peak of infectivity. The HA activity in the peak fraction seemed to be structually associated with virus particles. After fractionation of the virus by Nonidet P-40, the HA activity was found only in the fraction of the envelope material, indicating that the hemagglutinin is situated in the viral envelop.

Adsorption↗
PubMed1983

[Clinical study on preoperative chemotherapy of primary breast cancer. 2--A comparative study of CPA + FT-207 (5-FUDS) and CPA + FT-207 (5-FUDS) + MMC].

In 41 cases of primary breast cancer preoperative treatment was performed using 2 methods consisting CPA + FT-207 (5-FUDS) (for Group I) and CPA + FT-207 (5-FUDS) + MMC (for Group II) to determine clinical and histological efficacies. A daily dose of each anticancer drug was: CPA 50-200 mg, FT-207 200-600 mg, and 5-FUDS 200 mg orally, and MMC 4-20 mg intravenously. The mean total doses were 1.8 g, 6.3 g, 3.4 g and 26.3 mg, respectively. Reduction in tumor size was obtained in 11 cases (37.9%) in Group I and 6 cases (50.0%) in Group II. According to Ohboshi's criteria, histological efficacy as defined over Grade II a was seen in 5 cases (17.2%) in Group I and 6 cases (50.0%) in Group II, while the efficacy classified as Grade III was not seen in any of the cases. Although the clinical effect was not always consistent with the histological effect, there was a tendency of agreement between them in Group II. As to the dosages of anticancer drugs, more effective cases were seen when dosages of more than 25 mg/kg of CPA, 80 mg/kg of FT-207 (5-FUDS) or 0.5 mg/kg of MMC were used. Reduction in tumor size began to appear at 2 to 3 weeks after the initiation of treatment.

Adult↗