PowerPoint PresentationSlide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32Chapter 20 – Integrating Cells into Tissues-cells can adhere to each other and to the extracellular matrix (ECM)20.2. Cell-Cell and Cell-Matrix Adhesion MoleculesGeneral properties of cell adhesion molecules (CAMs)Three classes of cell junctionsClass I: Anchoring junctions 1) Adherens junctions2) Desmosomes3) HemidesmosomesCadherins are the cell adhesion molecules (CAMs) for adherens junctions and desmosomesStructure of cadherinCadherin levels and types can change – alters adhesion and cell migrationDesmosomal cadherins and desmosomesIntegrins and hemidesmosomesIntegrin heterodimers – for both ECM and as CAMsClass II: Tight junctionsCell ad hesi on mole cules a re occludin and claudi nCan a lter perme ability of tight junctio ns throu gh the G protein /cAMP pathwayCFTRNa+H2OH2ONa+Cl-Cl-BasolateralApicalGPCRACATPcAMPPKAPKAcAMPACPPKAcAMPRIn Cholera…ADP-ribosylationClass III: Gap-junctions: Cell adhesion molecule is connexon20.3. The Extracellular Matrix-Functions of the ECM:Basal laminaCollagens:1) Type IV collagen:2) Laminins:3 and 4) Perlecan and Nidogen20.4. The Extrace llular Matrix – Connective TissueTendo ns and ca rtilageKey comp onents:1) Fibrilla r collage ns2) Glycosam inogl ycans (GAGs)3) Proteog lycans4) Multiadh esive proteins5) Elast in1. Fibrillar collagens – types I and IIType I collagen:Type II collagen:2-3. Glycosaminoglycans (GAGs) and proteoglycans: glycoproteins that have GAGs linked to themProteoglycan aggregate (aggrecan) in cartilage:4. Multiadhesive matrix proteins (fibronectin)5. Elastin20.5. Adhesive Interactions in Motile and Nonmotile CellsIntegrins play a key roleRegulation of integrin-mediated adhesion1) Integrin binding2) Integrin expressionExtravasation-movement of leukocytes into tissues Key