Ali Hoda B M, Lysak Martin A, Schubert Ingo
Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany.
Genome. 2004 Oct;47(5):954-60. doi: 10.1139/g04-041.
Genomic in situ hybridization (GISH) is a useful tool to analyse natural polyploids, hybrid plants, and their backcross progenies as to their origin, genomic composition, and intergenomic rearrangements. However, in angiosperms with very small genomes (<0.6 pg/1 C), often only heterochromatic regions were found to be labeled. We have modified the GISH technique to label entire mitotic and meiotic chromosomes of Arabidopsis thaliana (2n = 10) and closely related species with very small genomes by using high concentrations of DNA (7.5-15 microg per probe per slide) or 5 microg of probe and long hybridization times (>60 h). According to our GISH data, Cardaminopsis carpatica (2n = 16) is most likely the diploid ancestor of the autotetraploid Arabidopsis arenosa (2n = 32). Furthermore, within the allotetraploid species Arabidopsis suecica (2n = 26), it was possible to elucidate the origin of chromosomes contributed by the parental species A. thaliana and A. arenosa for a specimen with 2n = 26 or a deviating chromosome number.
基因组原位杂交（GISH）是一种用于分析天然多倍体、杂交植物及其回交后代的起源、基因组组成和基因组间重排的有用工具。然而，在基因组非常小（<0.6 pg/1 C）的被子植物中，通常仅发现异染色质区域被标记。我们改进了GISH技术，通过使用高浓度的DNA（每张玻片每个探针7.5 - 15微克）或5微克探针以及较长的杂交时间（>60小时），对基因组非常小的拟南芥（2n = 10）及其近缘物种的有丝分裂和减数分裂染色体进行全标记。根据我们的GISH数据，卡氏碎米荠（2n = 16）很可能是同源四倍体砂生拟南芥（2n = 32）的二倍体祖先。此外，在异源四倍体物种瑞典拟南芥（2n = 26）中，对于一个2n = 26或染色体数目异常的样本，有可能阐明亲本物种拟南芥和砂生拟南芥所贡献染色体的起源。
