Positional cloning of gene that regulates proliferation and differentiation of embronic ectoderm.

• Project/Area Number: 13640616
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 遺伝
• Research Institution: The Institute of Physical and Chemical Research
• Principal Investigator: ABE Kuniya The Institute of Physical and Chemical Research Research & Development Team for Mammalian Cellular Dynamics, Team Leader, 動物変異動態解析技術開発チーム, チームリーダー (40240915)
• Co-Investigator(Kenkyū-buntansha): TAKAGI Nobuo Division of Bioscience, Graduate School of Environmental Earth Science, Hokkaido University , Professor, 大学院・地球環境科学研究科, 教授 (20001852)
• Project Period (FY): 2001 – 2002
• Project Status: Completed (Fiscal Year 2002)
• Budget Amount: ¥4,000,000 (Direct Cost: ¥4,000,000); Fiscal Year 2002: ¥1,500,000 (Direct Cost: ¥1,500,000); Fiscal Year 2001: ¥2,500,000 (Direct Cost: ¥2,500,000)
• Keywords: embryonic ectoderm / undifferentiated stem cells / cell proliferation and differentiation / t-complex / mouse genetics / 細胞増殖 / ポジショナルクローニング

Research Abstract

Mice homozygous for the tw5 allele arrest at gastrulation stage from defects associated with embryonic ectoderm proliferation/differentiation. The mutated gene mapped very close to H-2K gene in mouse MHC. To positionally clone the mutated gene, a BAC contig spanning 〜1000 kb of the corresponding genomic region was constructed. Combining our own sequencing analysis data of those BAC clones and genomic data available from public database, it was determined that the size of the tw5 critical region is 750 kb. EST database search, gene prediction program analysis and an experimental expression analysis suggest that there are possibly 36 genes within this region. Based on their expression profiles, this region is extremely rich in embryonically active genes, which are candidates for the tw5 embryonic lethality.
To understand the function of tclw5 gene product, we tried to determine the primary site of tclw5 gene action. Histological examination demonstrated that homozygotes of t^<w5> died at the gastrulation stage due to extensive death of the embryonic ectoderm cells while the extraembryonic ectoderm and the visceral endoderm were less affected in these embryos. By aggregation with diploid wild-type embryos, t^<w5>/t^<w5> cells were capable of contributing to all three germ layers. Thus, it is likely that tclw5 is not cell autonomous lethal. Furthermore, the hypothesis that tissues other than the embryonic ectoderm are the primary sites of tclw5 action was supported by the rescue of t^<w5>/t^<w5> embryos by aggregation with tetraploid embryos. Therefore, it is probable that the product of tclw5 is essential for the function of extraembryonic tissues.

Research Products

• [Publications] Li, Z.Z., Kondo, T., Murata, T., Ebersole, T.A., Nishi, T., Tada, K., Ushio, Y., Yamamura, K., Abe, K.: "Expression of Hqk encoding a KH RNA binding protein is altered in human glioma"Jpn.J.Cancer Res.. 90. 1-12 (2002)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Yamaki M., Isono, K., Takada, Y., Abe, K., Akasaka, T., Tanzawa, H., Koseki, H.: "The mouse Edr2 (Mph2) gene has two forms of mRNA encoding 90-and 36-kDa polypeptides"Gene. 288. 103-110 (2002)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Hidenori Kiyosawa, Kuniya Abe: "Speculations on the Role of Natural Antisense Transcripts in Mammalian X Chromosome Evolution"Cytogenetic and Genome Research. (印刷中). (2003)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Li,Z.Z., Kondo, T., Murata, T., Ebersole, T.A., Nishi, T., Tada, K., Ushio,Y., Yamamura, K., and Abe, K.: "Expression of Hqk encoding a KH RNA binding protein is altered in human glioma"Jpn. J. Cancer Res.. 90. 1-12 (2002)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Yamaki M., Isono, K., Takada, Y., Abe, K., Akasaka, T., Tanzawa, H. and Koseki, H.: "The mouse Edr2 (Mph2) gene has two forms of mRNA encoding 90- and 36-kDa polypeptides"Gene. 288. 103-110 (2002)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Hidenori Kiyosawa and Kuniya Abe: "Speculations on the Role of Natural Antisense Transcripts in Mammalian X Chromosome Evolution"Cytogenetic and Genome Research. (in press).
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Li, Z.Z., Kondo, et al.: "Expression of Hqk encoding a KH RNA binding protein is altered in human glioma"Jpn. J. Cancer Res.. 90. 1-12 (2002)
• [Publications] Yamaki, M., et al.: "The mouse Edr2 (Mph2) gene has two forms of mRNA encoding 90-and 36-kDa polypeptides"Gene. 288. 103-110 (2002)
• [Publications] Hidenori Kiyosawa, et al.: "Speculations on the Role of Natural Antisense Transcripts in Mammalian X Chromosome Evolution"Cytogenetic and Genome Research. (in press).
• [Publications] Isono, K., Abe, K., Tamaru, Y.et al.: "Molecular cloning, genetic mapping, and expression of mouse Sf3b1(SAP155)gene for the U2 snRNP component of spliceosome."Mammalian Genome. 12. 192-198 (2001)
• [Publications] Tada, M., Takahama, Y., Abe, K.et al.: "Nuclear reprogramming of somatic cells by in vitro hybridization with ES cells."Current Biology. 11. 1553-1558 (2001)
• [Publications] Yoshida, S., Ohbo, K., Takakura, A., et al.: "Sgn1, a basic helix-loop-helix transcription factor delineates the salivary gland duct cell lineage."Dev. Biol.. 240. 517-530 (2001)
• [Publications] Li, Z.Z., Kondo, T., Murata, T.et al.: "Expression of Hqk encoding a KH RNA binding protein is altered in human glioma."Jpn. J. Cancer Res.. 93. 1-12 (2002)