関連する実験動画
Updated: May 7, 2026

12:27
Measuring Peptide Translocation into Large Unilamellar Vesicles
Published on: January 27, 2012
シグナルペプチドペプチダゼは,エンドプラズマ網膜からの脱位のために必要です
Joana Loureiro1, Brendan N Lilley, Eric Spooner
1Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|June 2, 2006
まとめ
ヒューマンサイトメガロウイルス (HCMV) は,MHCクラスI分子を分解することで,免疫検出を回避します. この研究では,シグナルペプチドペプチダゼ (SPP) がHCMV US2タンパク質にとって決定的であることを確認しました.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
背景:
- ヒューマン・サイトメガロウイルス (HCMV) は,US2やUS11のような免疫エバシンを使って,免疫監視を回避します.
- これらのタンパク質は,感染した細胞表面上のMHCクラスIペプチド複合体のプレゼンテーションを妨げます.
- US11はDerlin-1を使用しているが,US2による変位のメカニズムとパートナーは不明である.
研究 の 目的:
- HCMV US2免疫エバシンと相互作用する宿主タンパク質を特定する.
- MHCクラスI重鎖脱位のためにUS2が採用した特定の経路を解明する.
- US2媒介の免疫逃避における特定されたパートナーの役割を調査する.
主な方法:
- US2 相互作用するパートナーを特定するための共免疫プレシピテーション.
- US2機能に対するタンパク質枯渇の影響を評価するために,RNA媒介による干渉.
- MHCクラスI重鎖の局所化と劣化の分析.
主要な成果:
- シグナルペプチドペプチダゼ (SPP) は,US2.2の活性形態の結合パートナーとして特定されました.
- RNAの干渉によるSPP濃度の低下は,US2媒介の重鎖変位を有意に抑制した.
- SPPの減少は,US11免疫エバシンによって媒介された変位に影響を与えませんでした.
結論:
- シグナルペプチドペプチダゼ (SPP) は,US2依存的脱位経路の重要な成分として関与しています.
- この発見は,SPP (内膜分裂プロテアゼ) が,エンドプラズマ網膜に関連した退廃において,新しい役割を担うことを示唆している.
- US2-SPPの相互作用を理解することは,HCMVの免疫回避戦略に関する新しい洞察を提供します.
関連する概念動画
ER Retrieval Pathway
In the secretory pathway, vesicles transport proteins from one cellular compartment to another in forward transport to deliver the protein to its correct location. Occasionally, misfolded proteins and incorrect proteins escape their original compartments, and a retrieval pathway is used to return the escaped proteins to their original compartment.
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
Directing Proteins to the Rough Endoplasmic Reticulum
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...
Cotranslational Protein Translocation
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...
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...
Insertion of Single-pass Transmembrane Proteins in the RER
Integral membrane proteins are proteins adhered to the lipid bilayer of a cell organelle or membrane. They can be of two types: transmembrane integral proteins that span the lipid bilayer and monotopic proteins that are attached to either side of the membrane but do not pass through it.
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Post-translational Translocation of Proteins to the RER
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...
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...
Export of Misfolded Proteins out of the ER
After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...

