Cell Interaction and Extracellular Matrix Quiz

Interactions that occur between cells and their surrounding environment, playing a crucial role in processes such as cell movement, growth, and differentiation.

The complex network of molecules outside of cells that provides structural support, organization, and communication within tissues.

Transmembrane receptors found on the surface of animal cells that mediate adhesion between cells and the extracellular matrix.

The ability of integrins to bind their ligands with moderate strength, allowing for dynamic and adjustable adhesion.

The presence of integrins in significantly higher concentrations on cell surfaces compared to other receptors.

A principle explaining how integrins bind ECM components with moderate strength, but their high concentration creates strong overall adhesion.

The process of cells moving from one location to another, guided by interactions with the ECM and other cells.

The 3D organization and structure of tissues and organs determined by cell-cell and cell-environment interactions.

A rare genetic disease resulting from mutations in genes responsible for elastin production, leading to weakened and loose skin.

Large molecules found in the Extracellular Matrix (ECM) composed of a core protein with attached glycosaminoglycans (GAGs).

Proteins like fibronectin and laminin that glue together ECM components and cells.

A family of enzymes that break down components of the Extracellular Matrix (ECM), enabling tissue repair and remodeling.

MMPs play a crucial role in wound healing by breaking down the ECM, allowing new tissue to grow and repair the damaged area.

Integrins are a family of cell surface receptors that mediate adhesion between cells and the extracellular matrix (ECM). They are composed of two subunits, alpha (α) and beta (β), which combine to form heterodimers.

Integrins have 18 α subtypes and 8 β subtypes, resulting in 24 known binding pairs of integrin heterodimers in humans. This diversity allows integrins to bind to a wide range of ECM molecules.

The α subunit of an integrin determines its ligand specificity, meaning which ECM molecule it will bind to. This specificity allows integrins to mediate cell-ECM adhesion in a tailored manner.

The β subunit of an integrin mediates mechanotransduction, the process of converting mechanical forces into chemical signals. This allows integrins to sense and respond to changes in the ECM.

Inside-out signaling refers to the process where signals from inside the cell trigger integrin activation. This activation makes integrins more receptive to binding ECM molecules.

Talin is a protein that binds to the β subunit of integrin and promotes its activation by inducing a conformational change. This change transitions the integrin from a bent, inactive state to an open, primed state ready to bind ECM.

Outside-in signaling refers to the process where interactions between integrins and ECM molecules trigger signals inside the cell. This is how integrins communicate with the cell about its surroundings.

Integrin-ECM interactions trigger focal adhesion formation, which are specialized structures that anchor the cell to the ECM. These adhesions also involve reorganization of the actin cytoskeleton, which gives the cell its shape and allows it to move.

Growth factor receptors can either elicit their own specific signals or interact with integrin signaling pathways to generate unique signals in response to ECM cues. This cross-talk allows cells to integrate information from multiple sources.

Different collagen types within the same fiber contribute to diverse structural and mechanical properties.

Collagen fibers are stabilized by hydrogen bonds formed between polypeptide chains, which require hydroxylated proline residues.

Hydroxylysine residues within collagen are modified by the attachment of sugars like galactose or glucose-galactose.

Lysine and hydroxylysine residues in collagen undergo oxidative deamination, leading to the formation of covalent cross-links that stabilize the fibers.

A deficiency of vitamin C (ascorbic acid) disrupts collagen synthesis, causing impaired collagen fiber formation.

Mutations in the genes encoding collagen proteins can lead to structural defects and disfunction in specific tissues.

Osteogenesis imperfecta is a genetic disorder characterized by bone fragility, caused by mutations in COL1A1 or COL1A2 genes.

Ehlers-Danlos syndrome is a group of connective tissue disorders caused by mutations in different collagen genes, impacting skin, joints, and blood vessels.

Elastin is a highly insoluble protein, resistant to chemical breakdown, that provides elasticity and resilience to tissues like blood vessels, lungs, and skin.

Elastic fibers are formed by the cross-linking of tropoelastin monomers onto a microfibril template, primarily composed of fibrillin.

A carbohydrate-rich layer on the cell surface, primarily composed of glycoproteins, that plays roles in cell interaction, protection, and signal transduction. It's commonly found in epithelia, like those lining the gastrointestinal tract.

A complex and organized network of molecules secreted by cells, crucial for providing structural support, cell-to-cell communication, and tissue organization. It serves as a scaffolding for tissues and regulates cell behavior.

A specialized sheet-like form of the ECM found beneath epithelia, it acts as a barrier and filter, and plays a critical role in cell adhesion and tissue organization. It is also known as the basal lamina.

Major components of the ECM that provide strength and flexibility to tissues. They are classified into three major groups: structural proteins, protein-carbohydrate complexes, and adhesive glycoproteins.

Fibrous proteins that provide tensile strength and support to the ECM. They are abundant in the body and are organized into fibers that can be found in various tissues.

A diverse family of glycoproteins that are the most abundant protein in the body. They are involved in providing tensile strength to the ECM and are synthesized by various cell types.

Elastin is a fibrous protein responsible for the elasticity and flexibility of tissues. It allows tissues to stretch and recoil, providing flexibility and resilience.

Large, complex molecules composed of a protein core attached to long chains of sugar molecules. These molecules play a vital role in providing structure and hydration to the ECM, acting as shock absorbers and lubricants.

The most abundant collagen type in the body, found in various tissues and responsible for providing the tensile strength of skin, bones, tendons, and ligaments.