Cell Adhesion · Structural Integrity External Sensing Migration Requlation of transport Communication adish Chapter 22 Kamm Chapter 2
Cell Adhesion • Structural Integrity • External Sensing • Migration • Regulation of Transport • Communication Lodish Chapter 22 Kamm Chapter 2
Overview of the types of molecules that bind cells to each other and to the extracellular matrix Cell-cell adhesions Cell-adhesion molecules Actin or intermediate filaments Transmembrane proteogly P membrane Cell matrix adhesions Collagen Glycosaminoglycans Matrix Fibronectin proteoglycan or laminin core protein
Overview of the types of molecules that bind cells to each other and to the extracellular matrix
Cell adhesion molecules and their characteristics Family Location and/or Comments function recognized Integrins focal adhesions (E)fibronectin, relatively low hemi-desmosomes, collagen, laminin, affinities leukocyte immunoglobulins, (KD- 10-10 ("spreading") O actin filaments mol/liter) cell-matrix adhesion but also in some circulating cells and carbohydrates require Ca endothelial cells rolling " adhesion Ig superfamily mportant in Integrins, (immunoglobulin) homophilic desmosomes (actin flame RD Kamm 2003
Cell adhesion molecules and their characteristics Family Location and/or Ligands Comments function recognized integrins focal adhesions, (E) fibronectin, relatively low hemi-desmosomes, leukocy te collagen, laminin, immunoglobulins, affinities (KD~ 10-6-10-8 ("spreading") (I) actin filaments mol/liter) adhesion, primarily cell-matrix adhesion but also in some cell-cell adhesions selectins circulating cells and carbohydrates require Ca 2+ endothelial cells, "rolling" adhesion Ig superfamily important in integrins, (immunoglobulin) cadherens immune response adherens junctions, homophillic (E) homophillic, require Ca 2+ desmosomes (I) actin filaments, intermediate filaments RD Kamm 2003
Adhesion complexes Junction tvpe Function Extracellular or ntracellular adjacent cell attachment attachment Adherens structural, cell-cell or cell- ECM proteins or actin filaments matrix djacent cell structural. cell-cell cadherin intermediate filaments Hemidesmosome structural cell-matrix basal lamina via intermediate ntegrins filaments Focal adhesions structural cell-matrix ECM proteins actin filaments Tight j ulate transport between cells and along cell Gap junctions cell-cell communication channels formed by connexin via ion and small molecule subun its Table 2. Adhe sion complexes
Adhesion complexes Junction type Function Extracellular or adjacent cell attachment Intracellular attachment Adherens structural, cell-cell or cellmatrix ECM proteins or cadherins in actin filaments Desmosome structural, cell-cell adjacent cell cadherin intermediate filaments Hemidesmosome structural, cell-matrix basal lamina via intermediate Focal adhesions Tight junction structural, cell-matrix regulate transport between cells and along cell membrane integrins ECM proteins via integrins filaments actin filaments Gap junctions cell-cell communication via ion and small molecule chann els formed by connex in subun its exchange Table 2. Adhe sion co mplexes
Gap junctions allow small molecules to pass between adjacent cells Gap-junction channel c Connexin Intra-cellula Connexin cOo" subunit Cell membrane
Gap junctions allow small molecules to pass between adjacent cells