テラチ トオル   TERACHI TORU
  寺地 徹
   所属   京都産業大学  生命科学部 産業生命科学科
   職種   教授
言語種別 英語
発行・発表の年月 2005/08
形態種別 その他
標題 Variations in a hotspot region of chloroplast DNAs among common wheat and Aegilops revealed by nucleotide sequence analysis
執筆形態 その他
掲載誌名 GENES & GENETIC SYSTEMS
出版社・発行元 GENETICS SOC JAPAN
巻・号・頁 80(4),pp.277-285
著者・共著者 CH Guo,T Terachi
概要 The second largest BamHI fragment (132) of the chloroplast DNA in Triticum (wheat) and Aegilops contains a highly variable region (a hotspot), resulting in four types of B2 of different size, i.e. B21 (10.5kb), B2m (10.2kb), B2 (9.6kb) and B2s (9.4kb). In order to gain a better understanding of the molecular nature of the variations in length and explain unexpected identity among B2 of Ae. ovata, Ae. speltoides and common wheat (T. aestivum), the nucleotide sequence between a stop codon of rbcL and a HindIII site in cemA in the hotspot was determined for Ae. ovata, Ae. speltoides, Ae. caudata and Ae. mutica. The total number of nucleotides in the region was 2808, 2810, 3302, and 3594 bp, for Ae. speltoides, Ae. ovata, A e. caudata and Ae. mutica, respectively, and the sequences were compared with the corresponding ones of Ae. crassa 4x, T aestivum and Ae. squarrosa. Compared with the largest B21 fragment of Ae. mutica, a 791bp and a 793 bp deletion were found in Ae. speltoides and Ae. ovata, respectively, and the possible site of deletion in the two species is the same as that of T aestivum. However, a deleted segment in Ae. ovata is 2 bp longer than that of Ae. speltoides (and T aestivum), demonstrating that recurrent deletions had occurred in the chloroplast genomes of both species. Comparison of the sequences from Ae. caudata and Ae. crassa 4x with that of Ae. mutica revealed a 289 bp and a 61 bp deletion at the same site in Ae. caudata and Ae. crassa 4x, respectively. Sequence comparison using wild Aegilops plants showed that the large length variations in a hotspot are fixed to each species. A considerable number of polymorphisms are observed in a loop in the 3' of rbcL. The study reveals the relative importance of the large and small indels and minute inversions to account for variations in the chloroplast genomes among closely related species.
DOI 10.1266/ggs.80.277
ISSN 1341-7568/1880-5779