cytoplasmic side of plasma membrane

Definition

Target type: cellularcomponent

The leaflet the plasma membrane that faces the cytoplasm and any proteins embedded or anchored in it or attached to its surface. [GOC:dos, GOC:tb]

The cytoplasmic side of the plasma membrane, also known as the inner leaflet, is a dynamic and complex region involved in a wide range of cellular processes. It is composed of a phospholipid bilayer, with the hydrophilic heads facing the cytoplasm and the hydrophobic tails facing the extracellular space. This leaflet interacts with various proteins, including transmembrane proteins, peripheral membrane proteins, and cytoskeletal elements, to regulate cellular functions.

Key components of the cytoplasmic side of the plasma membrane include:

- **Phospholipid bilayer:** The foundation of the membrane, it provides structural integrity and acts as a barrier to regulate the passage of molecules. The inner leaflet is enriched in phosphatidylserine and phosphatidylinositol, which play roles in signaling and membrane trafficking.
- **Transmembrane proteins:** These proteins span the entire membrane and serve as channels, pumps, receptors, and enzymes. They facilitate transport of molecules across the membrane and mediate cell-cell interactions.
- **Peripheral membrane proteins:** These proteins associate with the membrane through non-covalent interactions with the phospholipid head groups or transmembrane proteins. They act as signaling molecules, anchors for cytoskeletal elements, and regulators of membrane dynamics.
- **Cytoskeleton:** The cytoskeleton, particularly the actin filaments, interacts with the cytoplasmic side of the plasma membrane, providing structural support, facilitating cell motility, and regulating membrane trafficking.

The cytoplasmic side of the plasma membrane is involved in diverse cellular processes, including:

- **Signal transduction:** Receptor proteins on the membrane receive extracellular signals and transmit them into the cell, triggering specific cellular responses.
- **Transport of molecules:** Ion channels and pumps transport ions and small molecules across the membrane, maintaining cellular homeostasis and enabling communication between the cell and its environment.
- **Cell adhesion:** Adhesion molecules on the membrane mediate interactions with other cells and the extracellular matrix, contributing to tissue formation and function.
- **Endocytosis and exocytosis:** These processes allow the cell to take up nutrients and eliminate waste products by engulfing or releasing materials through the plasma membrane.

Overall, the cytoplasmic side of the plasma membrane is a dynamic and vital part of the cell, playing a crucial role in communication, transport, and structural integrity.'
"

Proteins (31)

Compounds (538)