シナプシンの膀に関連したCa2+/カルモジュリン依存タンパク質キナーゼIIは,シナプシンIの結合タンパク質である
F Benfenati1, F Valtorta, J L Rubenstein
1Institute of Human Physiology, University of Modena, Italy.
Nature
|October 1, 1992
まとめ
神経伝達物質の放出を調節するタンパク質であるシナプシンIは,Ca2+/カルモジュリン依存タンパク質キナーゼIIによるリン酸化により,シナプス胞から解離する. この相互作用はキナーゼによって媒介されます.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- シナプシンIは,シナプスベジクルと相互作用することによって神経伝達物質の放出を調節する重要なフォスフォタンパク質です.
- シナプシンIのCa2+/カルモジュリン依存タンパク質キナーゼII (CaMKII) によるリン酸化は,膀との相互作用を変化させ,神経伝達物質の放出に影響する.
- 神経伝達におけるリン酸化および脱リン酸化シナプシンIの異なる役割は,シナプス機能にとって重要である.
研究 の 目的:
- CaMKIIがシナプシンIと相互作用し,それを調節する分子メカニズムを解明する.
- シナプシンIとCaMKIIの結合とリン酸化に関与する特定のドメインを特定する.
- この相互作用が,シナプシンIがシナプスと関連し,神経伝達物質の放出にどのように影響するかを理解する.
主な方法:
- シナプシンIのC末端領域とシナプス膀に関連したCaMKIIの形態の間の結合相互作用を調査した.
- バイオケミカルアッセイを用いて,シナプシンIの結合パートナーとリン酸化酵素としてのCaMKIIの二重な役割を実証した.
- シナプシンIがシナプスから解離する際にCaMKII媒介のリン酸化が及ぼす効果を分析した.
主要な成果:
- シナプシンIのC端領域が,シナプス胞に関連したCaMKIIの調節領域と結合することを実証した.
- この特定の形式のCaMKIIが,シナプシンIの結合タンパク質として作用することを確認しました.
- CaMKIIがシナプシンIをリン酸化し,シナプスから解離を促進し,神経伝達物質の放出を促進することを示した.
結論:
- シナプスベシクルに関連したCaMKIIは,その調節ドメインを介して,シナプシンIに直接結合する.
- シナプシンIの結合タンパク質とリン酸化酵素としてのCaMKIIの二重機能は,神経伝達物質の放出を調節するために重要である.
- CaMKIIによるリン酸化は,シナプシンIの膀からの解離につながり,それによってシナプス伝送を調節します.
関連する概念動画
01:15Amplifying Signals via Second Messengers
Many receptor binding ligands are hydrophilic; they do not cross the cell membrane but bind to cell-surface receptors. Thus, their message must be relayed by second messengers present in the cell cytoplasm. There are several second messenger pathways, each with its own way of relaying information. For example, the G protein-coupled receptors can activate both phosphoinositol and cyclic AMP (cAMP) second messenger pathways. The phosphoinositol pathway is active when the receptor induces...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:03Anchoring Junctions
Anchoring junctions are multiprotein complexes that help cells connect to other cells and the extracellular matrix. Anchoring junctions are present on the lateral and basal surfaces of cells, providing strong and flexible connections. Focal adhesions are often formed due to cell interactions with the ECM substrata, which initiate signal transduction via kinase cascades and other mechanisms. Together, they provide stability and tissue integrity. There are three types of anchoring junctions:...
01:25Structure of Cadherins
The cadherins were one of the first cell adhesion molecules discovered; the term “cadherins” is based on their calcium-dependent adhering properties. The first cadherins discovered on the epithelial, neuronal, and placental cells were named E-cadherin, P-cadherin, and N-cadherin, respectively. These classical cadherins share sequence and structural similarities. Other cadherins, including those involved in cell signaling, are grouped into non-classical cadherins. This diversity of cadherins...
01:20Cell Adhesion Molecules - Types and Functions
Cell adhesion molecules (CAMs) are pivotal to multicellularity and the coordinated functioning of tissues and organ systems. They enable physical interactions between cells and provide mechanical strength to tissues. They also function as receptors for signal transmission across the plasma membrane. The CAMs are broadly classified into four families - integrins, cadherins, selectins, and immunoglobulin-like CAMs (IgCAMs).
CAM Families
The Integrin family of proteins is primarily involved in a...
CAM Families
The Integrin family of proteins is primarily involved in a...
01:31Immunoglobulin-like Cell Adhesion Molecules
Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...