Stable barley chromosomes without centromeric repeats
Stable barley chromosomes without centromeric repeats
复制标题
DOI：
10.1073/pnas.0504235102
复制
发表时间：
2005-07-12
影响因子：
11.1
通讯作者：
Endo, TR
中科院分区：
文献类型：
--
作者：
Nasuda, S;Hudakova, S;Endo, TR
已知卫星序列（AGGGAG）（n）和Ty 3/gypsy样反转录转座子定位于大麦着丝粒。利用一个杀配子系统，它诱导大麦染色体的染色体突变添加到普通小麦，我们获得了大麦染色体7 H（7 HS）的短臂的等染色体，缺乏大麦特异性卫星序列（AGGGAG），。两个端着丝粒衍生物的等染色体出现在后代：7 HS * 与和7 HS ** 没有近着丝粒C-带。FISH分析表明，这两个端体不仅缺乏大麦特异的着丝粒（AGGGAG），重复和逆转录元件，但也没有任何已知的小麦着丝粒串联重复，包括192-bp，250-bp，和尾序列。虽然它们缺乏这些着丝粒重复序列，但7 HS * 和7 HS ** 都表现出正常的有丝分裂和减数分裂传递。大麦着丝粒重复易位到小麦染色体4A没有产生双着丝粒染色体。间接免疫染色显示，所有测试的着丝粒特异性蛋白质（水稻CENH 3，玉米CENP-C，和推定的大麦同源的酵母动粒蛋白CBF 5和SKP 1）和组蛋白H3磷酸化的丝氨酸10和28定位在着丝粒区域的7 HS *。我们的结论是大麦着丝粒重复既不足够，也不是强制性的组装动粒，我们讨论了可能形成一个新的着丝粒在大麦染色体。
The satellite sequences (AGGGAG)(n) and Ty3/gypsy-like retrotransposons are known to localize at the barley centromeres. Using a gametocidal system, which induces chromosomal mutations in barley chromosomes added to common wheat, we obtained an isochromosome for the short arm of barley chromosome 7H (7HS) that lacked the barley-specific satellite sequence (AGGGAG),. Two telocentric derivatives of the isochromosome arose in the progeny: 7HS* with and 7HS** without the pericentromeric C-band. FISH analysis demonstrated that both telosomes lacked not only the barley-specific centromeric (AGGGAG), repeats and retroelements but also any of the known wheat centromeric tandem repeats, including the 192-bp, 250-bp, and Tail sequences. Although they lacked these centromeric repeats, 7HS* and 7HS** both showed normal mitotic and meiotic transmission. Translocation of barley centromeric repeats to a wheat chromosome 4A did not generate a dicentric chromosome. Indirect immunostaining revealed that all tested centromere-specific proteins (rice CENH3, maize CENP-C, and putative barley homologues of the yeast kinetochore proteins CBF5 and SKP1) and histone H3 phosphorylated at serines 10 and 28 localized at the centromeric region of 7HS*. We conclude that the barley centromeric repeats are neither sufficient nor obligatory to assemble kinetochores, and we discuss the possible formation of a novel centromere in a barley chromosome.