Kejnovsky Eduard, Kubat Zdenek, Hobza Roman, Lengerova Martina, Sato Shusei, Tabata Satoshi, Fukui Kiichi, Matsunaga Sachihiro, Vyskot Boris
Laboratory of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, CZ-612 65, Brno, Czech Republic.
Genetica. 2006 Sep-Nov;128(1-3):167-75. doi: 10.1007/s10709-005-5701-0.
Silene latifolia is a model dioecious plant with heteromorphic sex chromosomes. The Y chromosome is the largest in this species. Theoretical models propose an accumulation of repetitive DNA sequences in non-recombining parts of the Y chromosome. In this study, we isolated a BAC7H5 clone preferentially hybridizing to the Y chromosome of S. latifolia. Sequence analysis revealed that this BAC7H5 contains part of the chloroplast genome, indicating that these chloroplast sequences have accumulated on the Y chromosome and also may contribute to its large size. We constructed Y chromosome- and X chromosome-specific libraries and screened them to find Y- and/or X-linked copies of chloroplast sequences. Sequence analysis revealed higher divergence of a non-genic region of the chloroplast sequences located on the Y chromosome while genic regions tested showed only very low (max 0.9%) divergence from their chloroplast homologues.
宽叶蝇子草是一种具有异形性染色体的雌雄异株模式植物。该物种的Y染色体是最大的。理论模型提出，重复DNA序列在Y染色体的非重组区域积累。在本研究中，我们分离出一个BAC7H5克隆，它优先与宽叶蝇子草的Y染色体杂交。序列分析表明，这个BAC7H5包含叶绿体基因组的一部分，这表明这些叶绿体序列已经在Y染色体上积累，并且可能也促成了其较大的尺寸。我们构建了Y染色体和X染色体特异性文库，并对其进行筛选，以找到叶绿体序列的Y连锁和/或X连锁拷贝。序列分析显示，位于Y染色体上的叶绿体序列的一个非基因区域具有更高的分歧度，而测试的基因区域与其叶绿体同源物的分歧度仅非常低（最大0.9%）。
