関連する実験動画

Updated: May 2, 2026

Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides

Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides

Published on: June 19, 2012

SecAタンパク質は,分泌タンパク質がE. coliの膜ベジクルに転位するために必要です

R J Cabelli¹, L Chen, P C Tai

¹Department of Microbiology, State University of New York, Stony Brook, 11794.

|November 18, 1988

まとめ

SecAタンパク質は,E. coliのタンパク質転位に不可欠です. SecAの枯渇は,タンパク質の膜胞への移動を停止しますが,浄化されたSecAを追加すると,この機能が回復し,膜関連因子としての役割が確認されます.

科学分野:

分子生物学は分子生物学である.
細胞生物学細胞生物学
微生物学微生物学とは

背景:

細菌の内膜にタンパク質が転移することは,細胞の機能にとって極めて重要です.
SecAタンパク質は,このプロセスに関与する重要な成分です.

研究の目的:

E. coliのタンパク質転位におけるSecaの特定の役割を調査する.
SecAが必須であり,膜関連であるかどうかを判断する.

主な方法:

E. coli secA 珀色変異体 (secA13[Am]) を利用して,SecA 枯渇したシステムを作成しました.
野生型の抽出物からSecAを除去するために,anti-SecA抗体列を使用した.
再構成されたSecA欠乏した膜と,浄化されたSecAタンパク質.

主要な成果:

SecAが枯渇したシステムでは,OmpAとアルカリリンフォスファタゼの欠陥のあるコトランスレーションおよびポストトランスレーション転位が示されました.
SecAの除去により,タンパク質転位活動が廃止されました.
SecAを追加した際の転位活動の回復は,その本質的な機能を確認しました.

結論:

SecAは,E. coliのタンパク質転位に必要な,重要な膜関連タンパク質です.
このデータは,SecAが重要な転移因子としての役割を強く支持しています.

さらに関連する動画

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles

Published on: December 31, 2019

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features

Published on: March 16, 2022

関連する概念動画

Role of ER in the Secretory Pathway

Role of ER in the Secretory Pathway

Eukaryotic cells have a special pathway that enables communication between various intracellular membrane-bound compartments and also with the extracellular environment. This pathway is termed as the secretory pathway.
Components of the secretory pathway
About a third of proteins synthesized in the cell are sorted via the secretory route. They shuffle between different compartments in membrane-bound vesicles until they reach their final destination. The main intracellular compartments involved...

Overview of Secretory Vesicles

Overview of Secretory Vesicles

Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...

Insertion of Single-pass Transmembrane Proteins in the RER

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...

Post-translational Translocation of Proteins to the RER

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...

Protein Translocation Machinery on the ER Membrane

Protein Translocation Machinery on the ER Membrane

The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the...

Bacterial Translocation and Protein Secretion

Bacterial Translocation and Protein Secretion

Bacterial protein secretion involves translocation systems to ensure proteins reach their designated locations, including the plasma membrane, periplasm, outer membrane, or the external environment. These translocation systems are vital for bacterial physiology, supporting processes like membrane assembly, enzymatic activity in the periplasm, and interactions with the external environment. The division of labor between Sec and Tat pathways ensures efficiency in handling proteins with diverse...