DISTRIBUTION OF CENP-B BOXES REFLECTED IN CREST CENTROMERE ANTIGENIC SITES ON LONG-RANGE ALPHA-SATELLITE DNA ARRAYS OF HUMAN-CHROMOSOME-21
DISTRIBUTION OF CENP-B BOXES REFLECTED IN CREST CENTROMERE ANTIGENIC SITES ON LONG-RANGE ALPHA-SATELLITE DNA ARRAYS OF HUMAN-CHROMOSOME-21
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DOI：
10.1093/hmg/3.8.1245
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发表时间：
1994-08-01
影响因子：
3.5
通讯作者：
OKAZAKI, T
中科院分区：
文献类型：
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作者：
IKENO, M;MASUMOTO, H;OKAZAKI, T
利用小鼠-人体细胞杂交研究了人21号染色体α-DNA阵列的长程组织。在人类21号染色体的着丝粒区发现了两个不同的长α DNA阵列，即α 21-I和α 21-II位点。α 21-I基因座由11个单体重复单元（11 mer）的阵列组成，估计总长度为1.3 Mbp。CENP B盒是着丝粒蛋白B（CENP B）的结合位点，除了一个地方没有CENP B盒外，其它地方都有CENP B盒。另一个基因座α 21-II由α亚家族组成，与α 21-I基因座的组分同源性较低。从α 21-II基因座分离出总共呈现32个单体单元的五个不同的α型克隆。通过双色荧光原位杂交分析，α 21-I位点位于初级缢痕，而α 21-II位点则位于短臂一侧。此外，FISH和免疫荧光染色的组合表明，α 21-I位点是共定位和重叠的有丝分裂染色体和间期核的CREST着丝粒抗原位点，而α 21-II广泛分布。我们的数据表明，基因座α 21-I含有规则间隔的CENP-B盒在高频率和着丝粒抗原的组装位点可能涉及在人类和小鼠细胞中共同的着丝粒功能。
The long-range organization of alphoid DNA arrays of human chromosome 21 was investigated using a mouse - human somatic cell hybrid. Two distinct long alphoid DNA arrays, the loci alpha 21-I and alpha 21-II, were identified in the centromere region of human chromosome 21. The alpha 21-I locus, composed of an array of 11 monomer repeat units (the 11 mer), was estimated to have a total length of 1.3 Mbp. CENP-B boxes, the binding sites of the centromere protein B (CENP-B), appeared in every other monomer unit in the 11 mer except for one place where two monomer units were repeated without any CENP-B box. The other locus, alpha 21-II, was found to be composed of alphoid subfamilies with low homology to the components of alpha 21-I locus. Five different alphoid clones presenting 32 monomer units in total were isolated from the alpha 21-II locus. Sequences of these monomer units diverged between 71 - 89% and no unit containing a CENP-B box was found. By analysis using two color FISH, the alpha 21-I was localized to the primary constriction, whereas the alpha 21-II site was located slightly to the short arm side. Furthermore, a combination of FISH and immunofluorescent staining indicated that the alpha 21-I site was co-localized and overlapped with the CREST centromere antigenic site on mitotic chromosomes and in interphase nuclei, while alpha 21-II was distributed broadly. Our data suggest that the locus alpha 21-I containing regularly spaced CENP-B boxes at high-frequency and the assembly site of the centromere antigens may be involved in common centromere function in both human and mouse cells.