Effects of heavy-ion beams on chromosomes of common wheat, Triticum aestivum
Effects of heavy-ion beams on chromosomes of common wheat, Triticum aestivum
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DOI：
10.1016/j.mrfmmm.2009.05.001
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发表时间：
2009-10-02
影响因子：
2.3
通讯作者：
Tsujimoto, Hisashi
中科院分区：
文献类型：
--
作者：
Kikuchi, Shinji;Saito, Yoshinaka;Tsujimoto, Hisashi
为了研究重离子束辐照植物染色体的性质，将氮（N）离子束和氖（Ne）离子束对六倍体小麦染色体的影响与X射线的影响进行了比较。染色体畸变，如短染色体、环形染色体和双着丝粒染色体高频出现。经X射线、N离子束和Ne离子束照射在半致死剂量（LD - 50）下染色体断裂的平均数目分别为32、20和20。这些数值可能被低估了，因为没有计算染色体形态未改变的染色体重排。因此，我们随后使用了一个含有一对来自外源物种（大赖草）额外染色体的小麦品系，并通过基因组原位杂交观察了被辐照标记染色体的命运。该分析表明，50戈瑞的氖离子束诱导的断裂比X射线诱导的多约8倍。这一结果表明重离子束高频诱导染色体重排而非基因功能丧失。这进一步表明，在植物育种中已使用的离子束辐照产生的大多数新突变可能不是由普通的基因破坏而是由染色体重排引起的。（C）2009爱思唯尔B V版权所有。
To investigate the nature of plant chromosomes irradiated by heavy-ion beams, the effects of nitrogen (N) and neon (Ne) ion beams on hexaploid wheat chromosomes were compared with those of X-ray Chromosome aberrations, such as short, ring and dicentric chromosomes appeared in high frequency The average numbers of chromosome breaks at LD-50 by irradiation with X-ray, N and Ne ion beams were 32, 20 and 20, respectively These values may be underestimated because chromosome rearrangement without change in chromosome morphology was not counted. Thus, we subsequently used a wheat line with a pair of extra chromosomes from an alien species (Leymus racemosus) and observed the fate of the irradiated marker chromosomes by genomic in situ hybridization This analysis revealed that 50 Gy of neon beam induced about eight times more breaks than those induced by X-ray. This result suggests that heavy-ion beams induce chromosome rearrangement in high frequency rather than loss of gene function. This suggests further that most of the novel mutations produced by ion beam irradiation, which have been used in plant breeding, may not be caused by ordinary gene disruption but by chromosome rearrangements. (C) 2009 Elsevier B V All rights reserved.