The large-scale organization of the centromeric region in Beta species
The large-scale organization of the centromeric region in Beta species
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DOI：
10.1101/gr.162301
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发表时间：
2001-02-01
期刊：
影响因子：
7
通讯作者：
Schmidt, T
中科院分区：
文献类型：
--
作者：
Gindullis, F;Desel, C;Schmidt, T
在高等真核生物中，着丝粒的DNA组成显示出高度的变异，甚至在单个物种的染色体之间。然而，着丝粒DNA的长程组织显然遵循类似的结构规则。在我们的研究中，使用一组重复的DNA序列进行了比较分析的DNA在着丝粒区域的Beta物种，包括栽培和野生甜菜。我们的研究结果表明，这些地区的β基因组具有复杂的结构，并由可变的重复序列，包括卫星DNA，Ty 3-吉普赛样逆转录转座子，和微卫星。基于其分子特征和染色体分布确定的荧光原位杂交[FISH]，着丝粒重复DNA序列分为三类。通过高分辨率多色荧光原位杂交粗线期染色体和延长的DNA纤维，我们分析了着丝粒DNA序列的远程组织，导致野生甜菜物种平卧甜菜的着丝粒区域的结构模型。染色体突变体PRO 1和PAT 2含有一个单一的野生甜菜微型染色体与着丝粒活性，并提供了一个实验系统，连同克隆的着丝粒DNA序列，对个别植物着丝粒的分子分离。特别是，FISH延伸的DNA纤维的PRO 1微型染色体和脉冲场凝胶电泳的大限制性片段，使估计的阵列大小，散布模式，和更高的组织这些着丝粒相关的卫星家族。关于整体结构，β着丝粒区域显示出与少数动物和植物物种中的对应物的相似性，其中着丝粒已被详细分析。
In higher eukaryotes, the DNA composition of centromeres displays a high degree of variation, even between chromosomes of a single species. However, the long-range organization of centromeric DNA apparently follows similar structural rules. In our study, a comparative analysis of the DNA at centromeric regions of Beta species, including cultivated and wild beets, was performed using a set of repetitive DNA sequences. Our results show that these regions in Beta genomes have a complex structure and consist of variable repetitive sequences, including satellite DNA, Ty3-gypsy-like retrotransposons, and microsatellites. Based on their molecular characterization and chromosomal distribution determined by fluorescent in situ hybridization [FISH], centromeric repeated DNA sequences were grouped into three classes. By high-resolution multicolor-FISH on pachytene chromosomes and extended DNA fibers we analyzed the long-range organization of centromeric DNA sequences, leading to a structural model of a centromeric region of the wild beet species Beta procumbens. The chromosomal mutants PRO1 and PAT2 contain a single wild beet minichromosome with centromere activity and provide, together with cloned centromeric DNA sequences, an experimental system toward the molecular isolation of individual plant centromeres. In particular, FISH to extended DNA fibers of the PRO1 minichromosome and pulsed-field gel electrophoresis of large restriction fragments enabled estimations of the array size, interspersion patterns, and higher order organization of these centromere-associated satellite families. Regarding the overall structure, Beta centromeric regions show similarities to their counterparts in the few animal and plant species il in which centromeres have been analyzed in detail.