Molecular evolutionary studies on the origin of eukaryotes-Analyzes of informational macromolecules.

• Project/Area Number: 05640793
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: 系統・分類
• Research Institution: The Nihon University
• Principal Investigator: INOUE Tadashi The Nihon Univ. Dept. Agric. Veter. Med. Associate Prof., 農獣医学部, 助教授 (90124213)
• Project Period (FY): 1993 – 1994
• Project Status: Completed (Fiscal Year 1994)
• Budget Amount: ¥2,000,000 (Direct Cost: ¥2,000,000); Fiscal Year 1994: ¥600,000 (Direct Cost: ¥600,000); Fiscal Year 1993: ¥1,400,000 (Direct Cost: ¥1,400,000)
• Keywords: Nosema bombycis / Ribosomal RNA / Elongation factor / elongation factor / 微胞子虫 / rRNA遺伝子 / 分子進化 / 真核生物

Research Abstract

In order to investigate the evolutionary origin of eukaryotes, the sequences of ribosomal RNA genes and elongation factors of some microsporidia including Nosema bombycis which is believed to diverge at early stage of eukaryotes are examined by conventional methods.
The originisms used were two strains of N.bombycis, Vairimorpha sp. M12 and Pleistophora sp.. The target genes were PCR-amplified by using appropriate primers from the total genomic DNA which had been extracted from their spores. The complete sequences of the small subunit ribosomal RNA (SSU rRNA) genes were obtained from the above four samples. The lengths of the SSU rRNAs were shorter than those of ordinary prokaryotes, and the secondary structure models constructed from the sequence lacked several stems which are common for the eukaryotic SSU rRNAs. This fact may indicate that the microsporidian SSU rRNA stayd in the primitive evolutional stage.
Attempt to sequence the elongation factors was failed because of the lack of information for the appropriate primers to amplify the gene.

Research Products

• [Publications] Kawakami,Y.,Inoue,T.,Uchida,Y.,Hatakeyama,Y.,Iwano,H.and Ishinara,R.: "Specific amplification of DNA from reference strains of Nosema bombycis(Nosematidae,Microsporidia)." J.Seric.Sci.Jpn.64(in press). (1995)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Kawakami, Y., Inoue, T., Uchida, Y., Hatakeyama, Y., Iwano, H.and Ishihara, R.: "Specific amplification of DNA from reference starains of Nosema bombycis (Nosematidae, Microsporidia) ." J.seric.Sci.Jpn.64 (in press). (1995)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Kawakami,Y.,Inoue,T.,Uchida,Y.,Hatakeyama,Y.,Iwano,H.and Ishihara,R.: "Specific amplification of DNA from reference strains of Nosema bombycis(Nosematidae,Microsporidia)." J.Seric.Sci.Jpn.64(in press). (1995)