バクテリアの細胞分裂時に第二メッセンジャーc-di-GMPの非対称な分布
Matthias Christen1, Hemantha D Kulasekara, Beat Christen
1Department of Immunology, University of Washington, Seattle, WA 98195, USA.
Science (New York, N.Y.)
|June 5, 2010
まとめ
科学者たちは新しいバイオセンサを開発し,バクテリアのサイクルディガバノシンモノフォスファート (c-di-GMP) を視覚化しました. これらのセンサーは,細胞分裂中の細胞サイクル依存の変動と非対称な分布を明らかにし,細菌の粘着と運動性に影響を与えました.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- バクテリアの生理学
背景:
- サイクルディガノシンモノフォスファート (c-di-GMP) は,細菌にとって重要な第2の伝達物質である.
- c-di-GMPは,運動性,粘着性,およびバイオフィルム形成を含む重要な細胞プロセスを調節します.
- c-di-GMP濃度の正確な空間的および時間的な制御は,細菌の機能にとって不可欠です.
研究 の 目的:
- 細胞内c-di-GMP濃度のリアルタイムモニタリングのための新しいツールを開発する.
- 単一の細菌細胞内のc-di-GMPのダイナミックな行動と分布を調査する.
- バクテリアの細胞サイクルと分裂におけるc-di-GMPダイナミクスの役割を理解する.
主な方法:
- 遺伝子コード化された光共振エネルギー伝送 (FRET) ベースのバイオセンサが設計されました.
- 顕微鏡技術を使用して,生きている細菌のc-di-GMP濃度を視覚化しました.
- 研究は,Caulobacter crescentusとPseudomonas aeruginosaを含む多様なグラム陰性細菌種で実施されました.
主要な成果:
- c-di-GMP濃度の変動は,個々の細菌細胞内で成功裏に視覚化されました.
- c-di-GMP濃度は,細胞周期に依存する変化を示した.
- 細胞分裂中にc-di-GMPの非対称な分布が観察され,ポラライゼーションと子孫細胞の特徴と相関していました.
結論:
- 遺伝子コード化されたFRETバイオセンサは,c-di-GMPダイナミクスを研究するための強力な方法を提供します.
- 細胞周期に依存する調節とc-di-GMPの非対称的な分布は,細菌分裂の重要な特徴である.
- これらの発見は,c-di-GMPが細胞分裂と潜在的に細胞外臓器細胞の発達を調節する上で重要な役割を果たすことを示唆しています.
関連する概念動画
02:33Distribution of Cytoplasmic Content
Cytokinesis segregates a cell’s chromosomes and organelles into its daughter cells. Organelles divide and grow prior to cell division but cannot be synthesized de novo; therefore, cells must receive at least one copy of each organelle to survive. Currently, many of the details of how the organelles are distributed are not yet fully elucidated.
Distribution of cytoplasmic determinants
The cytoplasm contains various organelles, as well as salts, proteins, and water. The distribution of small...
Distribution of cytoplasmic determinants
The cytoplasm contains various organelles, as well as salts, proteins, and water. The distribution of small...
01:27Molecular Factors Affecting Cell Division
Several external and internal factors influence the initiation and inhibition of cell division. For instance, the death of nearby cells or the release of human growth hormone (hGH) promotes cell division. In contrast, lack of hGH or crowding of cells can inhibit cell division.
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...
01:45Positive Regulator Molecules
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
02:39Positive Regulator Molecules
Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
01:30Bacterial Signaling
Bacterial signaling can occur within bacteria (intracellular) or between bacteria (intercellular). At times, a group of bacteria behaves like a community. To achieve this, they engage in quorum sensing, the perception of higher cell density that causes changes in gene expression. Quorum sensing involves both extracellular and intracellular signaling. The signaling cascade starts with a molecule called an autoinducer (AI). Individual bacteria produce AIs that move out of the bacterial cell...
02:38Mitogens and the Cell Cycle
Mitogens and their receptors play a crucial role in controlling the progression of the cell cycle. However, the loss of mitogenic control over cell division leads to tumor formation. Therefore, mitogens and mitogen receptors play an important role in cancer research. For instance, the epidermal growth factor (EGF) - a type of mitogen and its transmembrane receptor (EGFR), decides the fate of the cell's proliferation. When EGF binds to EGFR, a member of the ErbB family of tyrosine kinase...