The Arabidopsis gene Terminal Flower 1 (TFL1) controls inflorescence meristem identity. A terminal flower (tfl1) mutant, which develops a terminal flower at the apex of the inflorescence, was induced by transformation with T-DNA. Using a plant DNA fragment flanking the integrated T-DNA as a probe, a clone was selected from a wild-type genomic library. Comparative sequence analysis of this clone with an EST clone (129D7T7) suggested the existence of a gene encoding a protein similar to that encoded by the cen gene which controls inflorescence meristem identity in Antirrhinum. Nucleotide sequences of the region homologous to this putative TFL1 gene were compared between five chemically induced tfl1 mutants and their parental wild-type ecotypes. Every mutant was found to have a nucleotide substitution which could be responsible for the tfl1 phenotype. This result confirmed that the cloned gene is TFL1 itself. In our tfl1 mutant, no nucleotide substitution was found in the transcribed region of the gene, and the T-DNA-insertion site was located at 458 bp downstream of the putative polyadenylation signal, suggesting that an element important for expression of the TFL1 gene exists in this area.

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A physical and genetic map of Clostridium perfringens strain 13 was constructed. C. perfringens strain 13 was found to have a 3.1-Mb chromosome and a large 50-kb plasmid, indicating that strain 13 has a relatively small genome among C. perfringens strains. A total of 313 genetic markers were mapped on the chromosome of strain 13. Compared with the physical and genetic map of C. perfringens CPN50, strain 13 had a quite similar genome organization, but with a large deletion (-400 kb) in a particular segment of the chromosome. Among several toxin genes, a beta2 toxin gene that is a novel virulence gene in C. perfringens was found to be located on the 50-kb plasmid.Key words: Clostridium perfringens, Genome map, Genome organization, Pulsed field gel electrophoresis, Virulence plasmid Clostridium perfringens is a Gram-positive anaerobic pathogen that causes gas gangrene or clostridial myonecrosis. The organism produces many extracellular toxins and enzymes that are involved in its pathogenicity (7, 11). Many virulence genes that may participate in this pathogenicity have been cloned and analyzed (13,14), and a physical and genetic map of the chromosome of C. perfringens has been determined (4, 5, 8).However, more precise genome organization should be elucidated through the use of a whole genomic approach, ex. whole genome sequencing, to develop a fuller understanding of the pathogenicity of C. perfringens. Recently, complete nucleotide sequences of many bacterial genomes have been determined, and it has become possible to analyze whole genomes of pathogenic bacteria. As to C. perfringens, a whole-genome-sequencing project has been started in our laboratory in collaboration with a Japanese consortium. C. perfringens strain 13 (10) has been widely used for genetic analysis of C. perfringens because of its ability to be efficiently transformed and to be mutated by homologous recombination (14). Taking advantage of its capacity for genetic manipulation, studies on the genetic regulation of toxin genes has been intensively undertaken in C. perfringens strain 13 (2,3,9,12,16,18 we chose strain 13 as a suitable strain for our wholegenome-sequencing project.In this study, to determine a rough genomic structure of strain 13 prior to the genomic sequencing, we constructed a physical and genetic map of strain 13. It was found that the overall genomic organization of the strain 13 chromosome was almost the same as that of CPN50, except for a large deletion of 400 kb. Moreover, strain 13 was found to contain a large plasmid carrying the beta2 toxin gene, one of the recently reported potent virulence genes of C. perfringens (6). Materials and MethodsStrains, plasmids, culture conditions, and general methods. C. perfringens strain 13 (10) was cultured as described previously at 37 C under anaerobic conditions (2). Escherichia coli DH5a was used as a host strain of plasmid pUC 18 and 19 derivatives (19). Standard molecular techniques were carried out as described elsewhere (15).Pulsed-field gel electrophoresis (PFGE). Two ...

Introduction Immune-mediated thrombotic thrombocytopenic purpura (iTTP), or acquired TTP (aTTP), is a life-threatening thrombotic microangiopathy that requires prompt treatment to improve patient outcomes. Caplacizumab is a von Willebrand factor (VWF)-directed antibody fragment that rapidly inhibits VWF-platelet interaction and prevents microthrombi formation in iTTP. Based on efficacy and safety demonstrated in the Phase 3 HERCULES trial, caplacizumab, in conjunction with therapeutic plasma exchange (TPE) and immunosuppression, is approved in the USA and EU for aTTP. The aim of this Phase 2/3 study (NCT04074187), conducted in Japan, was to evaluate the efficacy and safety of caplacizumab in Japanese patients with iTTP. Methods Japanese patients aged ≥18 years with a clinical diagnosis of iTTP who had received ≤1 TPE were enrolled in this single-arm, open-label study. Patients received caplacizumab in conjunction with TPE and immunosuppression, during daily TPE, and for ≥30 days after discontinuation of TPE. Treatment extension was allowed for ≤8 weeks in case of persistent ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) deficiency defined by the investigator and patients were followed for 4 weeks after end of caplacizumab treatment. Primary endpoint was the proportion of patients with a recurrence of iTTP during the overall study period, assessed in the per-protocol (PP) population; recurrence rate ≤20% was the success criterion. Key secondary endpoints were assessed in the PP and modified intention-to-treat (mITT) populations. Treatment-emergent adverse events (TEAEs) were assessed in the safety population. PP population included patients who completed treatment and follow-up per protocol or had a recurrence of iTTP; mITT and safety populations included patients with ≥1 dose of caplacizumab. All analyses were descriptive. The study was conducted in accordance with the Declaration of Helsinki. Results A total of 21 patients were enrolled and treated with caplacizumab; 6 patients discontinued (adverse event: n=2, physician decision: n=4), and 15 patients were included in the PP population. In the mITT population, median age (range) was 59 (22-86) years; 16 (76%) patients presented with an initial episode; median (range) platelet count at baseline was 21.5 (8-78) ×10 9/L;10 (48%) patients received rituximab; median duration (range) of caplacizumab exposure during the overall treatment period was 35 (7-69) days. All patients in the PP population had ADAMTS13 activity <10%. During the overall study period, 1 (7%) patient experienced iTTP recurrence. Median (95% confidence interval [CI]) time to platelet count response was 2.79 (1.76-3.59) days. Additional efficacy endpoints are shown in Table 1. The most common TEAEs were constipation and insomnia, reported in 43% and 29% of patients, respectively (Table 2); 2 treatment-emergent TE events were reported, cerebral infarction and deep vein thrombosis, in 1 patient each. One patient had a treatment-related serious bleeding event of pulmonary alveolar hemorrhage. No deaths occurred during the overall study period (treatment and follow-up). Conclusions In Japanese patients with iTTP, caplacizumab in conjunction with TPE and immunosuppression was associated with a low rate of recurrence of iTTP and fast normalization of platelet count and organ damage markers. These findings are comparable to those in the HERCULES study, in which caplacizumab was associated with 12% recurrence rate and median (95% CI) time to platelet count normalization of 2.69 (1.89-2.83) days (Scully M, et al. N Engl J Med. 2019;380 [4]:335-346). Caplacizumab was well tolerated, and no new safety signals were identified in the Japanese population. Funding This research was funded by Sanofi. Figure 1 Figure 1. Disclosures Miyakawa: Sanofi: Research Funding; Zenyaku Kogyo: Consultancy; Sanofi: Consultancy; argenx: Consultancy, Research Funding. Imada: Celgene Co., Ltd.: Honoraria; Bristol-Myers Squibb K.K.: Honoraria; Astellas Pharma Inc.: Honoraria; Chugai Pharmaceutical Co., Ltd.,: Honoraria; Sumitomo Dainippon Pharma Co., Ltd.: Honoraria; Otsuka Pharmaceutical Co. Ltd.: Honoraria; Takeda Pharmaceutical Co. Ltd.: Honoraria; Novartis Pharma K.K.: Honoraria. Ichikawa: Sanofi: Honoraria; AstraZeneca: Honoraria; Chugai: Honoraria. Handa: Daiichi Sankyo: Research Funding; Janssen: Honoraria; BMS: Honoraria; Ono: Honoraria; Sanofi: Honoraria, Research Funding; Abbvie: Honoraria; MSD: Research Funding; Shionogi: Research Funding; Celgene: Honoraria, Research Funding; Chugai: Research Funding; Kyowa Kirin: Research Funding; Takeda: Honoraria, Research Funding. Matsushita: Shire/Takeda: Honoraria; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bioverativ/Sanofi: Honoraria; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Educational and investigational support; CSL Behring: Honoraria; JB: Honoraria; KMB: Honoraria; Nichiyaku: Honoraria; Octapharm: Honoraria; Sysmex: Honoraria; Baltaxa/Shire/Takeda: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees, Other: Educational and investigational support; Pfizer: Membership on an entity's Board of Directors or advisory committees; Kirin: Honoraria. Hashimoto: Sanofi KK: Current Employment, Other: May hold shares and/or stock options. Ohshima: Sanofi KK: Current Employment, Other: May hold shares and/or stock options. Tahara: Sanofi KK: Current Employment, Other: May hold shares and/or stock options. Tanaka: Sanofi KK: Current Employment, Other: May hold shares and/or stock options. Matsumoto: Sanofi: Consultancy; Takeda: Consultancy; Alexion Pharma: Consultancy; Asahi Kasei Pharma: Research Funding; Chugai Pharmaceutical: Research Funding; Alfesa Pharma: Patents & Royalties: ELISA for measuring ADAMTS13 activity.