THE CENTROMERIC K-TYPE REPEAT AND THE CENTRAL CORE ARE TOGETHER SUFFICIENT TO ESTABLISH A FUNCTIONAL SCHIZOSACCHAROMYCES-POMBE CENTROMERE
THE CENTROMERIC K-TYPE REPEAT AND THE CENTRAL CORE ARE TOGETHER SUFFICIENT TO ESTABLISH A FUNCTIONAL SCHIZOSACCHAROMYCES-POMBE CENTROMERE
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DOI：
10.1091/mbc.5.7.747
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发表时间：
1994-07-01
影响因子：
3.3
通讯作者：
CLARKE, L
中科院分区：
文献类型：
--
作者：
BAUM, M;NGAN, VK;CLARKE, L
用微染色体分析系统研究了分裂酵母着丝粒功能的DNA需求。裂殖酵母着丝粒DNA的关键元件是着丝粒中心核心的一部分和在所有三条染色体上发现的2.1kb片段内的序列，作为K型(K/K‘’/dg)着丝粒重复的一部分。S.pombe着丝粒中心核心含有功能上多余的DNA序列，而在所有天然分裂酵母着丝粒中心两侧的反向重复基序对环形微染色体的着丝粒功能并不是必需的。着丝粒重复序列K‘’的串联拷贝与中心核心一起，对着丝粒功能产生相加作用，每增加一个拷贝，就会增加微小染色体有丝分裂的稳定性。然而，着丝粒重复序列B和L，以及中央核心和它的核心相关重复序列的一部分是必要的，不能取代K型序列。在着丝粒K型重复序列中已经确定了几个特定的蛋白结合位点，这与最近提出的着丝粒/基奈-变色功能模型相一致。
The DNA requirements for centromere function in fission yeast have been investigated using a minichromosome assay system. Critical elements of Schizosaccharomyces pombe centromeric DNA are portions of the centromeric central core and sequences within a 2.1-kilobase segment found on all three chromosomes as part of the K-type (K/K''/dg) centromeric repeat. The S. pombe centromeric central core contains DNA sequences that appear functionally redundant, and the inverted repeat motif that flanks the central core in all native fission yeast centromeres is not essential for centromere function in circular minichromosomes. Tandem copies of centromeric repeat K'', in conjunction with the central core, exert an additive effect on centromere function, increasing minichromosome mitotic stability with each additional copy. Centromeric repeats B and L, however, and parts of the central core and its core-associated repeat are dispensable and cannot substitute for K-type sequences. Several specific protein binding sites have been identified within the centromeric K-type repeat, consistent with a recently proposed model for centromere/kinet-ochore function in S. pombe.