Cell adhesion

Definition

Cell adhesion is the process by which cells attach to each other and to the extracellular matrix through specific molecules on their surfaces. This mechanism is crucial for maintaining tissue structure and function, as well as enabling communication between cells. Cell adhesion is facilitated by proteins known as cell adhesion molecules (CAMs), which play essential roles in a variety of biological processes, including development, immune response, and wound healing.

5 Must Know Facts For Your Next Test

1. Cell adhesion is vital for embryonic development, as it allows cells to form organized tissues and organs.
2. Different types of cell adhesion molecules, such as integrins and cadherins, mediate various types of cell interactions.
3. Dysfunction in cell adhesion can lead to diseases such as cancer, where cancer cells may lose their adhesion properties and metastasize.
4. Cell adhesion also plays a significant role in immune responses, allowing white blood cells to migrate to sites of infection or injury.
5. The interaction between cells and the extracellular matrix is crucial for providing signals that regulate cell behavior, including proliferation and differentiation.

Review Questions

• How do cell adhesion molecules contribute to the formation of tissues during embryonic development?
  • Cell adhesion molecules, like cadherins, are essential for the formation of tissues during embryonic development as they enable cells to stick together and communicate effectively. These interactions help organize cells into specific structures and layers, allowing them to form distinct tissues and organs. The ability of cells to adhere properly is crucial for establishing proper tissue architecture and ensuring that each cell type functions harmoniously within its environment.
• Discuss the role of integrins in mediating cell adhesion and how they interact with the extracellular matrix.
  • Integrins are a key family of cell adhesion molecules that mediate the attachment of cells to the extracellular matrix. They consist of two subunits that combine to form a functional receptor. Integrins bind to specific components of the ECM, such as fibronectin and collagen, enabling cells to anchor themselves. This anchorage not only provides structural support but also transmits signals from the ECM into the cell, influencing cellular behavior like migration, proliferation, and survival.
• Evaluate how alterations in cell adhesion mechanisms can contribute to cancer progression and metastasis.
  • Alterations in cell adhesion mechanisms can significantly contribute to cancer progression and metastasis by allowing cancer cells to detach from their original location and invade other tissues. Changes in the expression or function of adhesion molecules like cadherins can disrupt normal tissue architecture and promote a more invasive phenotype. When cancer cells lose their adhesive properties, they gain mobility, enabling them to travel through the bloodstream or lymphatic system and establish secondary tumors in distant organs, leading to poorer patient outcomes.

Related terms

Tight junctions: Specialized connections between adjacent cells that create a barrier to prevent the passage of molecules and ions through the space between cells.

Cadherins: A class of CAMs that mediate cell-cell adhesion by forming homophilic interactions, which are critical for the establishment and maintenance of tissue structure.

Extracellular matrix (ECM): A complex network of proteins and carbohydrates surrounding cells that provides structural and biochemical support to surrounding cells.