ミトコンドリア・トランスレーション・プラスティシティによる2つのゲノムの調整
Heike Rampelt1, Nikolaus Pfanner2
1Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany.
Cell
|October 8, 2016
まとめ
ミトコンドリアの呼吸連鎖複合体は 二重の遺伝的起源を持っています アセンブリファクターはヒトミトコンドリアのタンパク質合成とインポートを調整し,トランスレーション性可塑性をサブユニットインポートと結びつける.
科学分野:
- ミトコンドリア生物学
- 細胞呼吸
- タンパク質の生物生成
背景:
- ミトコンドリアの呼吸連鎖複合体は 細胞のエネルギー生産に不可欠です
- これらの複合体は核とミトコンドリアの両方のゲノムによってコードされたサブユニットから組み立てられます.
- サブユニット合成は細胞細胞とミトコンドリアリボソームの両方で発生し,複雑な調整が必要です.
研究 の 目的:
- ミトコンドリアの呼吸連鎖サブユニットの合成とインポートを調整するメカニズムを調査する.
- ヒトのミトコンドリア内のタンパク質輸入と変換制御を結びつける要因を特定する.
主な方法:
- 人間のミトコンドリアにおけるリボソーム新生鎖複合体の分析.
- 膜統合組成因子の特徴化
- 組立因子とリボソーム新生鎖複合体との関連を調査する.
主要な成果:
- ヒトミトコンドリア内のリボソーム新生鎖複合体と関連付けられる膜統合組成因子を特定した.
- これらの要因は,細胞溶液で合成されたサブユニットの輸入とトランスレーションの可塑性を調整することを示した.
- ミトコンドリア環境でタンパク質の合成と組み立ての間の 分子リンクを提供した.
結論:
- ミトコンドリア組立因子は,タンパク質合成とインポート経路を統合する上で重要な役割を果たします.
- この協調は,呼吸器連鎖複合体の効率的な生殖を保証する.
- この発見は,ミトコンドリアのプロテオスタシスとエネルギー代謝の調節に関する洞察を提供します.
さらに関連する動画
関連する概念動画
Animal Mitochondrial Genetics
9.9K
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...
9.9K
Export of Mitochondrial and Chloroplast Genes
4.4K
A eukaryotic cell can have up to three different types of genetic systems: nuclear, mitochondrial, and chloroplast. During evolution, organelles have exported many genes to the nucleus; this transfer is still ongoing in some plant species. Approximately 18% of the Arabidopsis thaliana nuclear genome is thought to be derived from the chloroplast’s cyanobacterial ancestor, and around 75% of the yeast genome derived from the mitochondria’s bacterial ancestor. This export has occurred...
4.4K
Coordination of Gene Expression Processes in Bacteria
813
The DNA replication, transcription, and translation processes are intricately coupled in bacteria, allowing efficient gene expression and rapid protein synthesis. While this physical and functional coordination is advantageous, it introduces challenges that bacteria overcome through specific regulatory mechanisms.Coupling of Replication, Transcription, and TranslationThe coupling of replication, transcription, and translation is a hallmark of bacterial gene expression. As the replisome unwinds...
813
Mitochondrial Protein Sorting
5.9K
Mitochondria are double-membrane organelles of the eukaryotes involved in cellular metabolism, signaling, ATP synthesis, and programmed cell death. Each of these processes requires specific proteins and enzymes that must be correctly sorted to the right mitochondrial subcompartment for the proper functioning of the organelle.
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
5.9K
Translocation of Proteins into the Mitochondria
13.6K
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,...
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,...
13.6K
Energy to Drive Translocation
2.9K
Mitochondrial protein import is powered by two distinct energy sources: ATP hydrolysis and electrochemical potential across the inner membrane. Newly synthesized precursors are bound by cytosolic chaperones of the Hsp70 family, which guide them to the import receptors on the mitochondrial surface. Utilizing the energy of ATP hydrolysis, Hsp70 chaperones transfer these precursors to the TOM receptors on the mitochondrial outer membrane.
Generally, polypeptides are unfolded by two distinct...
Generally, polypeptides are unfolded by two distinct...
2.9K


