哺乳动物线粒体DNA的合领先和滞后链合成
I J Holt1, H E Lorimer, H T Jacobs
1Department of Molecular Pathology, University of Dundee, Ninewells Medical School, United Kingdom. ih@mrc-dunn.cam.ac.uk
Cell
|March 18, 2000
概括
哺乳动物细胞利用两种不同的线粒体DNA (mtDNA) 复制模式. mtDNA复制数的变化与这些复制策略之间的转移有关.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 线粒体DNA (mtDNA) 复制对于细胞能量生产至关重要.
- 在哺乳动物细胞中控制mtDNA复制的精确机制尚未完全阐明.
- 了解mtDNA复制模式是理解细胞生物能学和疾病的关键.
研究的目的:
- 研究哺乳动物线粒体DNA (mtDNA) 复制的不同模式.
- 为了描述与每个模式相关联的复制中间体.
- 确定mtDNA拷贝数的变化与复制策略的关系.
主要方法:
- 两维阿加罗斯凝电泳用于mtDNA分析.
- 单链核酶消化被用于区分复制中间体.
- 对小鼠肝脏,人类胎盘和培养的哺乳动物细胞进行了分析.
主要成果:
- 确定了两种不同的mtDNA复制中间体类.
- 一个类,抵抗核酶消化,代表了合的领先和滞后链复制.
- 这种结合复制模式在mtDNA复制恢复过程中占主导地位,并在特定组织中观察到,而核酶敏感中间体,表明链异步复制,在未经处理的细胞中大量存在.
结论:
- 哺乳动物细胞拥有至少两种不同的mtDNA复制模式.
- 这些复制模式之间的平衡在mtDNA拷贝数发生变化时会发生变化.
- 这些发现为线粒体基因组维护的调节提供了新的见解.
相关概念视频
Replication in Eukaryotes
Overview
Lagging Strand Synthesis
During replication, the complementary strands in double-stranded DNA are synthesized at different rates. Replication first begins on the leading strand. Replication starts later, occurs more slowly, and proceeds discontinuously on the lagging strand.
There are several major differences between synthesis of the leading strand and synthesis of the lagging strand. 1) Leading strand synthesis happens in the direction of replication fork opening, whereas lagging strand synthesis happens in the...
There are several major differences between synthesis of the leading strand and synthesis of the lagging strand. 1) Leading strand synthesis happens in the direction of replication fork opening, whereas lagging strand synthesis happens in the...
The Replisome
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
Animal Mitochondrial Genetics
Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
Lagging Strand Synthesis
During replication, the complementary strands in double-stranded DNA are synthesized at different rates. Replication first begins on the leading strand. Replication starts later, occurs more slowly, and proceeds discontinuously on the lagging strand.
There are several major differences between synthesis of the leading strand and synthesis of the lagging strand. 1) Leading strand synthesis happens in the direction of replication fork opening, whereas lagging strand synthesis happens in the...
There are several major differences between synthesis of the leading strand and synthesis of the lagging strand. 1) Leading strand synthesis happens in the direction of replication fork opening, whereas lagging strand synthesis happens in the...
Replication in Eukaryotes
In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...


