操作子是C. elegans中常见的染色体组织形式
D A Zorio1, N N Cheng, T Blumenthal
1Department of Biology, Indiana University, Bloomington 47405.
Nature
|November 17, 1994
概括
在C. elegans中,基因转录与其他真核生物不同. 研究人员发现,许多基因被转录在操作子中,类似于细菌,具有特定的拼接模式.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- 细胞基因通常会经历个体转录.
- 一些Caenorhabditis elegans基因在类似操作子的集群中表现出多基斯特朗转录.
- 拼接的领导者SL2在这些操作中具有跨拼接的特征.
研究的目的:
- 调查C. elegans基因组中操作子的流行情况.
- 为了确定高层真核生物中多基斯特龙转录的程度.
主要方法:
- 基因集群的全基因组识别.
- 测试七个已识别的集群,以检测它们的跨拼接特异性.
- 调查报告了C. elegans基因用于转接拼接模式.
主要成果:
- 所有七个测试的基因集群都表现出多基斯特朗转录的特征.
- 大约70%的C. elegans前mRNAs是转接的.
- 高达25%的C. elegans基因被转录到操作子中.
结论:
- 在C. elegans中,类似操作子的结构很普遍.
- 这一发现挑战了对真核生物基因转录的传统观点.
- 在真核生物中,C. elegans为研究子样基因组织提供了一个模型.
相关概念视频
02:09Operons
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02:32Position-effect Variegation
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01:51Lampbrush Chromosomes
In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, Rückert observed LBCs in shark egg cells and coined the term "lampbrush chromosomes" because they looked like brushes used to clean kerosene lamps.
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops resemble the...
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02:04Polytene Chromosomes
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02:09Operons
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01:23Operon Model
The operon model represents a fundamental mechanism of gene regulation in prokaryotes, enabling coordinated expression of genes involved in related metabolic or functional pathways. Operons consist of structural genes, a promoter, and an operator, with transcription regulated by repressors, activators, and small effector molecules.Structure and Function of OperonsAn operon is a cluster of structural genes transcribed together under the control of a single promoter. The promoter region...