Chapter 20 – Integrating Cells into Tissues

Flashcards related to cell and ECM adhesion, junctions, and ECM functions.

Cell-adhesion molecules (CAMs)

Mediate direct cell-cell adhesions (homotypic and heterotypic), and adhesion receptors mediate cell-matrix adhesions.

Extracellular matrix (ECM)

A dynamic, complex meshwork of proteins and polysaccharides that contributes to the structure and function of a tissue.

Integrating Cells into Tissues

Cell-cell and cell–extracellular matrix (ECM) interactions are critical for assembling cells into tissues, controlling cell shape and function, and determining the developmental fate of cells and tissues.

Cadherins and integrins

Mediate cell-cell and cell-ECM junctions.

Tight junctions

Define epithelial cell polarity and regulate extracellular (paracellular) flow of water and solutes from one side of the epithelium to the other.

Gap junctions

Connect the cytoplasms of adjacent cells for metabolic and electrical coupling.

Cell-Cell and Cell–Extracellular Junctions

Anchoring junctions that include adherens junctions, focal contacts, desmosomes, and hemidesmosomes.

Simple columnar epithelia

Elongated cells including mucus-secreting cells and absorptive cells.

Simple squamous epithelia

Thin cells lining blood vessels and many body cavities

Transitional epithelia

Several layers of cells with different shapes--line certain cavities subject to expansion and contraction

Stratified squamous (nonkeratinized) epithelia

Line surfaces such as the mouth and vagina, and resist abrasion.

Adherens junctions function

Shape, tension, signaling, force transmission

Desmosomes function

Strength, durability, signaling

Hemidesmosomes function

Shape, rigidity, signaling

Focal junctions function

Shape, signaling, force transmission, cell movement

Adherens junctions principal CAMs

Cadherins

Desmosomes principal CAMs

Desmosomal cadherins

Hemidesmosomes principal CAMs

Integrin (α6ẞ4)

Focal, fibrillar, and 3-D adhesions principal CAMs

Integrins

Tight junctions CAMs

Occludin, claudins, JAMS

Gap junctions CAMs

Connexins, innexins, pannexins