cell adhesions

Flashcards covering key vocabulary and concepts related to cell adhesion and cell junctions, based on lecture notes.

Epithelium

Tightly packed cells forming mechanical and chemical barriers, relying on close cell-cell contacts with polarity and apical/basal surfaces. Sheets of cells held together by junctions with each other and the basal lamina.

Mesenchyme

Connective tissue with loosely packed cells surrounded by extracellular matrix (ECM), allowing extensive cell movement.

Epithelial-mesenchymal transition (EMT)

The process where epithelial cells can transform into mesenchymal cells, important in embryonic development, inflammation, and cancer metastasis.

Tight Junctions

Occluding junctions that seal cells together into sheets, forming an impermeable barrier.

Gap Junctions

Communicating junctions that allow the exchange of chemical/electrical information between cells.

Adherens Junctions

Anchoring junctions that attach cells (and their cytoskeleton) to other cells, providing mechanical support and linking to actin microfilaments.

Desmosomes

Anchoring junctions that attach cells (and their cytoskeleton) to other cells, providing mechanical support and linking to intermediate filaments.

Focal Adhesions

Anchoring junctions that attach cells to the extracellular matrix (ECM), linking to actin filaments.

Hemidesmosomes

Anchoring junctions that attach cells to the basal lamina, linking to intermediate filaments.

Claudin and Occludin

Transmembrane proteins that form tight junctions, sealing the space between cells.

Connexins

Proteins that form gap junctions, creating hydrophilic channels between cells for the exchange of ions and small molecules.

Cadherins

Transmembrane glycoproteins that mediate cell adhesion in the presence of Ca2+ ions, important for tissue organization.

Integrins

Main cell surface receptors that bind to adhesive glycoproteins in the ECM, linking the extracellular matrix to the cell's cytoskeleton.

Homophilic Interactions

Adhesion between similar molecules, such as cadherins on adjacent cells.

Heterophilic Interactions

Adhesion between different molecules.

Selectins

Cell adhesion molecules involved in the rolling adhesion of leukocytes to endothelial cells during leukocyte extravasation.

ECM (Extracellular Matrix)

A structural support network made up of diverse proteins, sugars, and other components that influences cellular processes like migration, wound healing, and differentiation.