Takao Sekiya
Sasaki Institute
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Takao Sekiya.
Scientific Reports | 2016
Tomoaki Fujii; Shin-ichiro Tsunesumi; Hiroshi Sagara; Miyo Munakata; Yoshihiro Hisaki; Takao Sekiya; Yoichi Furukawa; Kazuhiro Sakamoto; Sumiko Watanabe
Methylation of histone tails plays a pivotal role in the regulation of a wide range of biological processes. SET and MYND domain-containing protein (SMYD) is a methyltransferase, five family members of which have been identified in humans. SMYD1, SMYD2, SMYD3, and SMYD4 have been found to play critical roles in carcinogenesis and/or the development of heart and skeletal muscle. However, the physiological functions of SMYD5 remain unknown. To investigate the function of Smyd5 in vivo, zebrafish were utilised as a model system. We first examined smyd5 expression patterns in developing zebrafish embryos. Smyd5 transcripts were abundantly expressed at early developmental stages and then gradually decreased. Smyd5 was expressed in all adult tissues examined. Loss-of-function analysis of Smyd5 was then performed in zebrafish embryos using smyd5 morpholino oligonucleotide (MO). Embryos injected with smyd5-MO showed normal gross morphological development, including of heart and skeletal muscle. However, increased expression of both primitive and definitive hematopoietic markers, including pu.1, mpx, l-plastin, and cmyb, were observed. These phenotypes of smyd5-MO zebrafish embryos were also observed when we introduced mutations in smyd5 gene with the CRISPR/Cas9 system. As the expression of myeloid markers was elevated in smyd5 loss-of-function zebrafish, we propose that Smyd5 plays critical roles in hematopoiesis.
Biological Chemistry | 2004
Masahiko Shiraishi; Adam J. Oates; Xu Li; Ying H. Chuu; Takao Sekiya
Abstract The technique of segregation of partly melted molecules (SPM) is a convenient and efficient method to isolate DNA fragments associated with CpG islands. The approach is conceptually simple and uses denaturant gradient gel electrophoresis to separate DNA molecules digested with restriction endonucleases. The SPM methodology has successfully been applied to the identification of genes from anonymous, unsequenced DNA fragments and CpG islands methylated in human cancer. In this article the theoretical background and practical application of the SPM method is reviewed.
Scientific Reports | 2017
Naoyuki Okita; Yoshikazu Higami; Fumio Fukai; Masaki Kobayashi; Miku Mitarai; Takao Sekiya; Takashi Sasaki
Now, the quantification of proinsulin/insulin contents within organisms tends to be evaluated only by enzyme-linked immunosorbent assay (ELISA), although assessing the adequacy of results by some quantification method is important. Remarkably, few scientific papers use detection by Western blotting (WB), another immunological assay, of proinsulin/insulin. We found two problems with quantification of insulin and proinsulin by general WB: the shape of an insulin band in gel electrophoresis is distorted, and the retention potency to a blotting membrane of the peptide hormones (mainly insulin) is low. We solved the first problem by optimizing the sodium dodecyl sulfate concentration in the sample buffer and the second problem by glutaraldehyde fixation following treatment with a blocking solution for a short time. The improvements were confirmed by quantification of proinsulin/insulin in standards, MIN6c4 cell lysates, and MIN6c4 culture supernatants. Furthermore, we showed that the modified WB is applicable to other diabetes-associated peptide hormones: insulin analogs, glucagon, GLP-1s, somatostatins, ghrelins, and pancreatic polypeptide. Our data showed that the modified WB can contribute to qualitative or quantitative analyses of diabetes-associated peptides by providing analytical information based on electrophoresis, although ELISA, which is an almost exclusive method in the quantification of peptide hormones, supplies only numerical data.
Oncotarget | 2018
Shigeo Yamaguchi; Tomoaki Fujii; Yuki Izumi; Yuki Fukumura; Min Han; Hideki Yamaguchi; Tomomi Akita; Chikamasa Yamashita; Shunsuke Kato; Takao Sekiya
During next generation sequencing (NGS) analysis, many missense mutations were found in a well-known oncogene, many of which were variant of uncertain significance mutations. We recently treated an adult patient with pancreatoblastoma by chemotherapy. Using an NGS cancer panel, we found a previously unreported missense mutation in the 1835 codon of the adenomatous polyposis coli (APC) gene. We also found a heterogeneous mutation in the 1835 codon of the APC gene in the patients germline by Sanger sequencing. Although this patient did not have a history of familial adenomatous polyposis, functional analysis suggested the R1835G mutant APC showed attenuated repression of Wnt/β-catenin signaling activity. This is the first report showing a novel APC missense mutation involved in the onset of adult pancreatoblastoma.
Oncogene | 2002
Masahiko Shiraishi; Azumi Sekiguchi; Michael J. Terry; Adam J. Oates; Yuji Miyamoto; Ying H. Chuu; Miyo Munakata; Takao Sekiya
Correction to: Oncogene (2002) 21, 2309–2319.doi:10.1038/sj.onc.1205297 Since the publication of the above paper, the authors have identified errors in the spelling of their names and E-mail address. The correct spellings are shown on the left in each instance below:David TULASNE not David TULASHE,Sylvie REVENEAU not Syline REVENEAU,veronique.
Proceedings of the Japan Academy Series B: Physical and Biological Sciences | 2001
Masahiko Shiraishi; Azumi Sekiguchi; Adam J. Oates; Michael J. Terry; Yuji Miyamoto; Takao Sekiya
Proceedings of the Japan Academy. Ser. B: Physical and Biological Sciences | 1996
Masahiko Shiraishi; Takao Sekiya
Biological & Pharmaceutical Bulletin | 2003
Shiro Koizume; Takao Sekiya; Masahiko Shiraishi
日本分子生物学会年会プログラム・講演要旨集 | 1996
Adam J. Oates; Fumie Hosoda; Misao Ohki; Takao Sekiya; Masahiko Shiraishi
Proceedings of the Japan Academy, Series B | 1996
Masahiko Shiraishi; Takao Sekiya