在E.crassus中高度重复的元素的发育协调大规模切除
C L Jahn1, M F Krikau, S Shyman
1Department of Biological Sciences, University of Illinois, Chicago 60680.
Cell
|December 22, 1989
概括
在E.crassus中Tec1元素在微核基因组中丰富,但在宏核基因组中不存在. 它在宏核发育的早期切除,形成染色体外的圆圈.
科学领域:
- * 分子生物学 * 分子生物学
- * 遗传学 在遗传学方面
- * 细胞生物学 细胞生物学
背景情况:
- * E. crassus Tec1 元素是一种重复的DNA序列.
- * 在微核基因组中存在大量副本.
- * Tec1 在宏核基因组中显著缺席.
研究的目的:
- * 调查E. crassus Tec1元素在宏观核发育过程中的行为和命运.
- * 描述Tec1切除及其基因组定位的基础分子机制.
主要方法:
- * 对Tec1.1.的染色体外圆形和集成形式的限制映射.
- *对Tec1 termini和圆形DNA形式的序列分析.
- * 在宏核基因组形成过程中分析Tec1元素的行为.
主要成果:
- * 在宏核发育过程中,tec1元素主要形成染色体外圆圈.
- * 圆形Tec1形式对BAL31核酶表现出耐药性,这表明在反向重复终点处的切除.
- * 序列分析证实了循环Tec1中的头对头反向重复,切割发生在宏核发育的早期.
结论:
- * E. crassus Tec1 元素在宏核发育过程中从基因组中经历精确的切除.
- * 切割发生在过程的早期,与DNA复制和多基形成相吻合.
- * 这种编程的DNA消除确保了体质巨核基因组中Tec1的缺失.
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