Biomedical subjects

Kohji Suzuki

Publications and source records attributed to Kohji Suzuki.

4 recordsLinked to original sources

PubMed2004

Transcriptional profiling of genes responsive to abscisic acid and gibberellin in rice: phenotyping and comparative analysis between rice and Arabidopsis.

We collected and completely sequenced 32,127 full-length complementary DNA clones from Oryza sativa L. ssp. japonica cv. "Nipponbare." Mapping of these clones to genomic DNA revealed approximately 20,500 transcriptional units (TUs) in the rice genome. For each TU, we selected 60-mers using an algorithm that took into account some DNA conditions such as base composition and sequence complexity. Using in situ synthesis technology, we constructed oligonucleotide arrays with these TUs on glass slides. We targeted RNAs prepared from normally grown rice callus and from callus treated with abscisic acid (ABA) or gibberellin (GA). We identified 200 ABA-responsive and 301 GA-responsive genes, many of which had never before been annotated as ABA or GA responsive in other expression analysis. Comparison of these genes revealed antagonistic regulation of almost all by both hormones; these had previously been annotated as being responsible for protein storage and defense against pathogens. Comparison of the cis-elements of genes responsive to one or antagonistic to both hormones revealed that the antagonistic genes had cis-elements related to ABA and GA responses. The genes responsive to only one hormone were rich in cis-elements that supported ABA and GA responses. In a search for the phenotypes of mutants in which a retrotransposon was inserted in these hormone-responsive genes, we identified phenotypes related to seed formation or plant height, including sterility, vivipary, and dwarfism. In comparison of cis-elements for hormone response genes between rice and Arabidopsis thaliana, we identified cis-elements for dehydration-stress response as Arabidopsis specific and for protein storage as rice specific.

Abscisic Acid↗

PubMed2003

Antisense transcripts with rice full-length cDNAs.

BACKGROUND: Natural antisense transcripts control gene expression through post-transcriptional gene silencing by annealing to the complementary sequence of the sense transcript. Because many genome and mRNA sequences have become available recently, genome-wide searches for sense-antisense transcripts have been reported, but few plant sense-antisense transcript pairs have been studied. The Rice Full-Length cDNA Sequencing Project has enabled computational searching of a large number of plant sense-antisense transcript pairs. RESULTS: We identified sense-antisense transcript pairs from 32,127 full-length rice cDNA sequences produced by this project and public rice mRNA sequences by aligning the cDNA sequences with rice genome sequences. We discovered 687 bidirectional transcript pairs in rice, including sense-antisense transcript pairs. Both sense and antisense strands of 342 pairs (50%) showed homology to at least one expressed sequence tag other than that of the pair. Microarray analysis showed 82 pairs (32%) out of 258 pairs on the microarray were more highly expressed than the median expression intensity of 21,938 rice transcriptional units. Both sense and antisense strands of 594 pairs (86%) had coding potential. CONCLUSIONS: The large number of plant sense-antisense transcript pairs suggests that gene regulation by antisense transcripts occurs in plants and not only in animals. On the basis of our results, experiments should be carried out to analyze the function of plant antisense transcripts.

DNA, Antisense↗

PubMed2003

Collection, mapping, and annotation of over 28,000 cDNA clones from japonica rice.

We collected and completely sequenced 28,469 full-length complementary DNA clones from Oryza sativa L. ssp. japonica cv. Nipponbare. Through homology searches of publicly available sequence data, we assigned tentative protein functions to 21,596 clones (75.86%). Mapping of the cDNA clones to genomic DNA revealed that there are 19,000 to 20,500 transcription units in the rice genome. Protein informatics analysis against the InterPro database revealed the existence of proteins presented in rice but not in Arabidopsis. Sixty-four percent of our cDNAs are homologous to Arabidopsis proteins.

Alternative Splicing↗

PubMed2002

Treatment of a patient with hemophilia A and hepatitis C virus-related cirrhosis by living-related liver transplantation from an obligate carrier donor.

BACKGROUND: Decompensated hepatitis C virus (HCV)-related cirrhosis is the main indication for liver transplantation. We report the first successful living-related liver transplantation in a 49-year-old hemophilia A patient with end-stage HCV-related cirrhosis using a graft obtained from his 20-year-old daughter, an obligate carrier. METHODS: The donor's autologous fresh-frozen plasma rich in factor VIII (FVIII) by treatment with 1-deamino-8-D-arginine vasopressin was prepared before the operation. At induction, 1-deamino-8-D-arginine vasopressin was given to the donor to increase plasma FVIII level. In addition, autologous fresh-frozen plasma containing high FVIII concentrate was infused intraoperatively. The right lobe was harvested from the donor and transplanted orthotopically. The recipient was treated postoperatively with recombinant FVIII and immunosuppressive agents. RESULTS: The donor did not receive recombinant FVIII or allogenic blood during perioperative periods. No bleeding was encountered in the donor perioperatively. The recipient showed a steady increase in FVIII activity postoperatively and was discharged 40 days after transplantation. Ribavirin and interferon-alpha were provided for 3 months postoperatively to prevent potential recurrence of HCV infection. Serum HCV-RNA by RT-PCR became negative after such treatment. CONCLUSIONS: End-stage liver disease in patients with hemophilia A can be an indication for living-related liver transplantation. Furthermore, a graft from a living-related donor with hemophilia A carrier seems to be suitable provided such individuals receive adequate support for coagulopathies.

Deamino Arginine Vasopressin↗