テロメラー DNA を結合したヒトのテロメラーゼホロ酵素の構造
George E Ghanim1, Adam J Fountain1, Anne-Marie M van Roon1
1Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
Nature
|April 22, 2021
まとめ
高解像度の冷凍EMはヒトのテロメラーゼの構造を明らかにし,その活性部位と相互作用を詳細に説明します. これはテロメラーゼの活性を標的とした 新しいがん治療法の開発の基盤となります
科学分野:
- 生物化学
- 分子生物学
- 構造生物学
背景:
- テロメラーゼはテロメアの長さを維持し ゲノムの安定性には不可欠です
- テロメラーゼの調節不全は 癌や様々な病気と関連しています
- これまでの低解像度構造は 治療開発に欠かせていました
研究 の 目的:
- テロメア DNA に結合するヒトテロメラーゼホロ酵素の高解像度構造を決定する.
- テロメラーゼ活性部位内のDNAとRNAの結合界面を明らかにする.
- テロメラーゼの活性に影響する突然変異の構造的基礎を理解する.
主な方法:
- クリオ電子顕微鏡 (cryo-EM) を使って,4 Å未満の解像度を達成した.
- テロメアDNAと複合したヒトテロメラーゼホロ酵素の構造を決定した.
- 分析は,主要な分子相互作用と構造成分を特定することに焦点を当てました.
主要な成果:
- テロメア DNA に結合するヒトテロメラーゼホロ酵素の4 Å 未満の解像度構造が得られた.
- 活性部位における重要なDNAとRNA結合インターフェースが特定されました.
- ヒストンH2A-H2BダイマーがテロメラーゼRNAに結合していることが判明し,RNAの折りたたみにおける役割を示唆した.
結論:
- この高解像度構造は ヒトのテロメラーゼの組み立てと活性部位を 前例のない詳細で示しています
- これらの構造的特徴を理解することは 標的型がん治療の開発に不可欠です
- テロメラーゼ関連疾患の 分子病理学への洞察を 提供しています
関連する概念動画
02:41Telomeres and Telomerase
25.4K
In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded...
25.4K
02:41Telomeres and Telomerase
6.3K
6.3K
01:29Replication in Eukaryotes
15.8K
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...
15.8K
02:31Replication in Eukaryotes
184.9K
Overview
184.9K
00:55DNA Helicases
23.0K
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
23.0K
03:01The Replisome
36.8K
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...
36.8K