Controlled exchange of chromosomal arms reveals principles driving telomere interactions in yeast
Controlled exchange of chromosomal arms reveals principles driving telomere interactions in yeast
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DOI：
10.1101/gr.6687808
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发表时间：
2008-02-01
期刊：
影响因子：
7
通讯作者：
Gasser, Susan M.
中科院分区：
文献类型：
--
作者：
Schober, Heiko;Kalck, Veronique;Gasser, Susan M.
芽殖酵母基因组中的32个端粒聚集在3至7个核周灶中。虽然个别端粒和端粒灶是在不断的运动，优先并列的一些端粒已经得分。为了研究指导这种长距离相互作用的原理，我们对染色体末端进行了差异标记，并开发了一种自动三维测量工具，用于确定两个端粒之间的距离。在酵母中，所有染色体末端终止于TG（1-3）和中间重复元件，但端粒亚组也在亚端粒编码结构域中具有广泛的同源性。我们发现，高达21 kb的> 90%的序列同一性不促进间期细胞中的端粒配对。为了测试独特的序列元件、臂长度或染色体区域是否影响并置，我们将末端结构域或整个染色体臂从一条染色体交换到另一条染色体。我们发现Tel 6 R的远端10 kb促进与Tel 6 L的相互作用，但仅当两个端粒存在于同一染色体上时。通过控制染色体5号染色体右臂的长度和序列组成，我们证实了在相对的等长染色单体臂上的端粒之间的接触是有利的。这些结果可以解释为酵母着丝粒和端粒的极性Rabl排列，其通过允许等长染色体臂之间在后期接触而促进端粒配对。
The 32 telomeres in the budding yeast genome cluster in three to seven perinuclear foci. Although individual telomeres and telomeric foci are in constant motion, preferential juxtaposition of some telomeres has been scored. To examine the principles that guide such long-range interactions, we differentially tagged pairs of chromosome ends and developed an automated three-dimensional measuring tool that determines distances between two telomeres. In yeast, all chromosomal ends terminate in TG(1-3) and middle repetitive elements, yet subgroups of telomeres also share extensive homology in subtelomeric coding domains. We find that up to 21 kb of > 90% sequence identity does not promote telomere pairing in interphase cells. To test whether unique sequence elements, arm length, or chromosome territories influence juxtaposition, we reciprocally swapped terminal domains or entire chromosomal arms from one chromosome to another. We find that the distal 10 kb of Tel6R promotes interaction with Tel6L, yet only when the two telomeres are present on the same chromosome. By manipulating the length and sequence composition of the right arm of chr 5, we confirm that contact between telomeres on opposite chromatid arms of equal length is favored. These results can be explained by the polarized Rabl arrangement of yeast centromeres and telomeres, which promote to telomere pairing by allowing contact between chromosome arms of equal length in anaphase.