与其他细胞DNA聚合酶相比,DNA聚合酶 ζ具有强大的反转录酶活性
Ryan Mayle1, William K Holloman2, Michael E O'Donnell1
1Howard Hughes Medical Institute and the Department of DNA Replication, The Rockefeller University, New York, New York, USA.
The Journal of biological chemistry
|October 25, 2024
概括
酵母Pol ζ是RNA模板DNA双链断裂 (DSB) 修复的主要酶. 这项研究发现,与其他DNA聚合酶 (Pol) 相比,Pol ζ表现出优异的逆转录酶活性,促进RNA引导的DNA修复.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 使用RNA模板可以修复DNA双链断裂 (DSB).
- 这一过程需要逆转录酶活性来从RNA模板中合成DNA.
- 转移合成 (TLS) DNA聚合酶 (Pol) 是由于它们的杂乱性而成为候选者.
研究的目的:
- 为了比较Saccharomyces cerevisiae中所有七种已知的核DNA聚合酶的逆转录酶活动.
- 为了确定参与RNA模板DSB修复的主要DNA聚合酶.
主要方法:
- 从Saccharomyces cerevisiae中净化所有七种核DNA聚合酶.
- 对每个纯化聚合酶的逆转录酶活性进行检测.
- 在RPA和RFC/PCNA的存在下分析Pol ζ活动.
主要成果:
- 酵母Pol ζ的反转录酶活性明显高于人类Pol η和其他DNA聚合酶.
- 波兹的逆转录酶活性独立于RPA和RFC/PCNA.
- 聚 ζ以分布式的方式合成了与RNA模板互补的DNA.
结论:
- 聚 ζ 是主要的DNA聚合酶,在Saccharomyces cerevisiae中的RNA模板DSB修复中起作用.
- 这些发现支持TLS聚合酶在非正规DNA修复途径中的作用.
相关概念视频
Proofreading
6.2K
Synthesis of new DNA molecules is carried out by the enzyme DNA polymerase, which adds nucleotides on the daughter strand complementary to the template DNA strand. DNA polymerase has a higher affinity to add the correct base and ensures fidelity during DNA replication. Furthermore, it exhibits proofreading activity during replication, using an exonuclease domain that cuts off incorrect nucleotides from the nascent DNA strand.
Errors During Replication are Corrected by the DNA Polymerase...
Errors During Replication are Corrected by the DNA Polymerase...
6.2K
Translesion DNA Polymerases
9.9K
Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
9.9K
The Replisome
33.1K
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 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...
33.1K
Eukaryotic RNA Polymerases
23.7K
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
23.7K
Replication in Eukaryotes
170.4K
Overview
170.4K
Bacterial RNA Polymerase
29.1K
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
29.1K


