Mettl15-Mettl17は,早期から遅いプレミトリボソームへの移行を調節する

Yury Zgadzay¹, Claudio Mirabello², George Wanes³

¹Department of Integrative Structural Biology, Institute of Genetics and Molecular and Cellular Biology, University of Strasbourg, Illkirch, France.

Structure (London, England : 1993)

|August 29, 2025

まとめ

メチルトランスフェラーゼMettl15とMettl17は,ミトコンドリアのリボソーム小サブユニット生殖を調節するために協力する. リボソームの適切な形成を保証し早期と後期の組み立て段階を結びつけます

科学分野:

分子生物学
生物化学
細胞生物学

背景:

ミトコンドリアのリボソーム小サブユニット (SSU) のバイオゲネシスは細胞呼吸に不可欠です.
メチルトランスファーゼMettl15とMettl17を含むアセンブリファクターは,この複雑なプロセスを導く.
これらの要因は異なる段階で作用しますが,正確な調整は不明です.

研究の目的:

ミトリボソームのSSU生殖におけるメチルトランスファーゼMettl15とMettl17の協力メカニズムを解明する.
構造データとダイナミックデータを統合し,組み立て時の相互作用をモデル化します.
これらの要因がSSU形成の初期段階と後期段階をどのように結びつけるかを理解する.

主な方法:

トリパノソーマ・ブルセイと哺乳類の同類体の構造データを統合した.
タンパク質とrRNAの相互作用と構造変化を分析するための分子動力学シミュレーション.
Mettl15とMettl17の役割を特定するための生化学的分析

主要な成果:

Mettl17はアセンブリの初期に結合し,潜在的にMettl15の採用のプラットフォームとして機能します.
Mettl15は後期段階に関与し,その活動はMettl17の放出と形状の変化に依存する.
Mettl15とMettl17の連続的な作用と相互作用は,組み立て段階から最終的な熟成までの移行を容易にする.

結論:

Mettl15とMettl17は協力してミトリボソームのSSU生殖を調節する.
ダイナミックな相互作用によりリボソームの配列が順調に進行し完成します
この研究は,これらの重要な組み立て因子の協調的な作用のメカニズムモデルを提供します.

キーワード:

トリパノソーマバイオゲネシスクリオ・エムメチルトランスフェラーゼミトコンドリアミトリボソーム分子動力学リボソームアセンブリ翻訳

さらに関連する動画

09:33

Rapid Isolation of the Mitoribosome from HEK Cells

Published on: October 4, 2018

11.2K

10:27

Dual DNA Rulers to Study the Mechanism of Ribosome Translocation with Single-Nucleotide Resolution

Published on: July 8, 2019

6.4K

関連する概念動画

01:19

Translocation of Proteins into the Mitochondria

3.2K

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...

3.2K

02:53

Ribosomal RNA Synthesis

13.4K

Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...

13.4K

01:34

Directing Proteins to the Rough Endoplasmic Reticulum

7.4K

The organelle-specific signaling sequences direct proteins synthesized in the cytosol to their final destination like ER, mitochondria, peroxisomes, etc. Some of the proteins directed to ER are then trafficked via vesicles to other organelles within the cell or the extracellular environment through the Golgi complex. For example, the rough ER synthesizes soluble proteins for transportation to the lysosomes or secretion out of the cell. It can also synthesize transmembrane proteins that can...

7.4K

01:27

Post-translational Translocation of Proteins to the RER

5.9K

A sizable fraction of proteins destined for ER are first synthesized in the cell cytosol and then transported across the ER membrane–a process called post-translational translocation. Similar to cotranslationally translocated proteins, these proteins also use the Sec translocon complex to enter the ER lumen.
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...

5.9K

01:20

Cotranslational Protein Translocation

7.6K

Translocation of proteins across membranes is an ancient process that occurs even in bacteria and archaebacteria. In fact, the components of the translocation machinery are still conserved between prokaryotes and eukaryotes.
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...

7.6K

01:39

Mitochondrial Precursor Proteins

2.6K

Mitochondrial precursors are partially unfolded or loosely folded polypeptide chains. Newly synthesized precursors are inhibited from spontaneously folding into their native conformation by the cytosolic chaperones, heat shock proteins 70 (Hsp70), and mitochondrial import stimulation factors (MSFs). Precursors bound to MSFs are guided to the TOM70-TOM37 receptors, while precursors bound to Hsp70 chaperones are targetted to TOM20-TOM22 receptor complexes.
Most of the mitochondrial...