COMPOSITION AND CHROMOSOMAL LOCALIZATION OF CETACEAN HIGHLY REPETITIVE DNA WITH SPECIAL REFERENCE TO THE BLUE WHALE, BALAENOPTERA-MUSCULUS
COMPOSITION AND CHROMOSOMAL LOCALIZATION OF CETACEAN HIGHLY REPETITIVE DNA WITH SPECIAL REFERENCE TO THE BLUE WHALE, BALAENOPTERA-MUSCULUS
复制标题
DOI：
10.1007/bf00292384
复制
发表时间：
1989-11-01
期刊：
影响因子：
1.6
通讯作者：
WIDEGREN, B
中科院分区：
文献类型：
--
作者：
ARNASON, U;WIDEGREN, B
在蓝鲸中研究了三种高度重复的DNA成分-常见的鲸类成分、重（富含GC）卫星和轻（富含AT）卫星。基于共同组分的三个重复和重卫星的八个重复，确定共同组分和重卫星的共有序列。组成所有鲸目动物-齿鲸（齿鲸）和须鲸（须鲸）-大部分的串联的普通鲸目动物基因组的重复长度为1 760 bp，分析的三个克隆显示高度一致。该重复序列包含一个72 bp的序列，具有二分体对称性和显著的链内互补性。重复序列的其余部分包含独特的序列。蓝鲸的重卫星重复单位为422 bp。这个组件也是串联组织的。大约一半长度的重复序列构成一个独特的序列，另一半是由亚重复序列与TTAGGG作为一个常见的基序。这颗轻卫星尚未测序，其基本重复单位尚未确定。用~ 3 H标记的克隆片段作探针，通过原位杂交确定了三种组分的染色体定位。常见的鲸类成分位于大多数间隙和终端C带。重卫星主要出现在终端C波段。当这两个组件杂交到相同的终端C-带，定位的重卫星是远端的常见的鲸类组件。这两个组件共享本地化的轻卫星，位于着丝粒C-带在少数染色体对。
Three highly repetitive DNA components - the common cetacean component, the heavy (GC-rich) satellite and the light (AT-rich) satellite - were studied in the blue whale. Consensus sequences of the common component and the heavy satellite were determined on the basis of three repeats of the common component and eight repeats of the heavy satellite. The tandemly organized common cetacean component, which comprises a large portion of all cetacean - both odontocete (toothed whale) and mysticete (whalebone whale) - genomes has a repeat length of 1,760 bp and the three clones analysed showed a high degree of conformity. The repeat contains a 72 bp sequence with dyad symmetry and striking intrastrand complementarity. The rest of the repeat comprises a unique sequence. The repeat unit of the heavy satellite of the blue whale is 422 bp. Also this component is tandemly organized. About half the length of the repeat constitutes a unique sequence and the other half is made up of subrepeats with TTAGGG as a frequent motif. The light satellite has not been sequenced and its basic repeat unit has not yet been identified. The chromosomal localization of the three components was determined by in situ hybridization using 3H-labelled cloned fragments as probes. The common cetacean component was located in most interstitial and terminal C-bands. The heavy satellite occurred primarily in terminal C-bands. When the two components hybridized to the same terminal C-bands, the localization of the heavy satellite was distal to that of the common cetacean component. Neither component shared localization with the light satellite which is located in centromeric C-bands in just a few chromosome pairs.