エッジホッグパターニング活動:カルボキシ-ターミナル自動処理ドメインによって媒介されるリポフィリック変異の役割
J A Porter1, S C Ekker, W J Park
1Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.
Cell
|July 12, 1996
まとめ
ヘッジホッグ (Hh) タンパク質前駆体の自己触媒処理には,シグナリングドメインを変更するチオエステル中間体が含まれています.
科学分野:
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学について
- タンパク質生化学 タンパク質生化学
背景:
- ヘッジホッグ (Hh) タンパク質前駆体は,その活性信号形式を生成するために,自己触媒処理を受けます.
- この自己処理がHh信号の生体生成と機能に果たす正確な役割は不明のままである.
- 以前の研究では,切断されたHhがシグナル伝達活動を保持することを示し,カルボキシ末端ドメインの必要性を疑問視しました.
研究 の 目的:
- Hhタンパク質の自己処理のメカニズムと機能的意義を解明する.
- 胚の発達中のHh信号伝達の空間的調節における自己処理の役割を調査する.
- この処理メカニズムが他の分泌されるタンパク質に保存されているかどうかを判断する.
主な方法:
- Hhタンパク質前駆体の自己触媒処理反応を調査した.
- 処理されたHh信号領域の生化学的性質を分析した.
- 胚のモデルにおける,切断された未加工のHhタンパク質の発達効果を評価した.
主要な成果:
- 自動処理反応は,内部のチオエステル中間体を通して行われます.
- この処理は,コヴァレンスの改変をもたらし,Hhシグナリングドメインの水性特性を高めます.
- 切断され,未処理のHhタンパク質は,胚の誤ったパターンを引き起こし,空間的なHh信号調節における自動処理の役割を示しています.
結論:
- ヘッジホッグタンパク質の自動処理は,活性信号分子を生成するための重要なメカニズムです.
- 自動処理は,Hh信号領域の空間的およびサブセルラー分布に影響を与え,発達パターンに影響を与えます.
- 特定された自己処理メカニズムは,他の分泌されるタンパク質の生体生成に関連している可能性があります.
関連する概念動画
01:32Pinching-off of Coated Vesicles
3.2K
Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...
3.2K
01:26Protein Modifications in the RER
5.7K
Modification of secretory and transmembrane proteins entering the rough ER begins in the ER lumen. These modifications aid in protein folding and stabilize the acquired tertiary structure. Protein modifications in the rough ER co-occur at different stages of protein folding.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal...
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal...
5.7K
01:28Assembly of the Lipid Bilayer in the ER
3.2K
Biological membranes are more than just a barrier separating cell cytoplasm from the outside environment. They are highly dynamic and help maintain the integrity and physiological stability of the cells as well as membrane-bound organelles. Membranes also play vital roles in cell-to-cell and intracellular communication.
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
3.2K
01:39Mechanism of Filopodia Formation
2.5K
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
2.5K
01:31Mechanism of Lamellipodia Formation
3.1K
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...
3.1K
00:59Mechanisms of Membrane Domain Formation
3.2K
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with...
Another mechanism for membrane domain formation involves membrane proteins interacting with...
3.2K