滞后链合成与色素组件的内在合
Duncan J Smith1, Iestyn Whitehouse
1Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA.
Nature
|March 16, 2012
概括
欧核生物Okazaki碎片的大小是由核细胞体决定的. 新生的染色体组装影响了奥卡扎基片段处理,揭示了DNA复制和染色体组织之间的联系.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 染色体生物学 染色体生物学
背景情况:
- DNA复制是半断续续的,滞后的链被合成成碎片,称为Okazaki碎片.
- 欧核生物Okazaki碎片及其处理并未得到充分理解,特别是它们与快速组装核细胞的关系.
- 新生DNA上的核细胞组件可能会影响奥卡扎基片段处理,反之亦然.
研究的目的:
- 为了研究奥卡扎基碎片大小和核细胞组织在真核细胞之间的关系.
- 为了确定与核子相对的奥卡扎基碎片结合结的精确位置.
- 探索新生染色体组合在Okazaki碎片终结中的作用.
主要方法:
- 在Saccharomyces cerevisiae中对Okazaki碎片进行深度测序.
- 对结合结分布与核细胞位相对应的分析.
- 染色质组合和滞后链聚合酶过程性的扰乱.
主要成果:
- 在Saccharomyces cerevisiae中,Okazaki碎片的大小与核细胞重复长度相关.
- 结合连接主要在核体中点附近,而不是在链接DNA中.
- 破坏色素组合或聚合酶过程性会改变Okazaki碎片的大小和分布.
结论:
- 新生染色体组合在终止奥卡扎基片段合成中发挥着作用.
- 滞后链DNA合成和染色体组装之间存在相互联系.
- 这项研究提供了第一个高分辨率的真体内分析的真核生物Okazaki碎片.
相关概念视频
02:31Chromosome Replication
Before a cell can divide, it must accurately replicate all of its chromosomes, including the DNA and its associated histone and non-histone proteins. This process begins at numerous origins of replication during the S phase of the cell cycle in each of a cell’s chromosomes simultaneously. Certain nucleotides can act as origins of replication, but these sequences are not well defined - especially in complex, multi-cellular, eukaryotic species. The length of DNA that spans an origin of...
01:59Lagging 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...
03:01The 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...
02:05Duplication of Chromatin Structure
The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation.
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
01:59Lagging 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...
03:01The 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...