Post on 26-Mar-2015
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Chapter 22
Integrating Cells into Tissues
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22.0 Schematic overview of the types of molecules that bind cells to each other and to the extracellular matrix
Figure 22-1
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22.1 There are five principal classes of cell-adhesion molecules (CAMs)
Figure 22-2
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22.1 Cadherins mediate Ca2+-dependent homophilic cell-cell adhesion
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22.1 N-CAMs mediate Ca2+-independent homophilic cell-cell adhesion
Figure 22-3
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Regulação da ligação de N-CAM por sialização
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22.1 Selectins and other CAMs participate in leukocyte extravasation
Figure 22-4
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22.1 Cadherin-containing junctions connect cells to one another
Figure 22-5
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A Matriz Extracelular (ECM)
Presente em todos os tecidos Organiza as células em tecidos Coordena a função as células Providencia um caminho para a migração celular Moléculas na matriz activam vias de trasdução
que regulam o crescimento, divisão e expressão génica das células
As células interagem com a ECM através de CAMPrincipalmente integrinasTambém selectinas e proteoglicanos
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22.2 Integrins mediate weak cell-matrix and cell-cell interactions
Cell-matrix adhesion is modulated bychanges in the activity and number ofIntegrins (plaquetas; maturação S.I.)
De-adhesion factors promote cellmigration and can remodel the cell surface
• Desintegrinas (pequenos péptidos com RGD)
• Proteases que degradam a ECM
• Matrix specific Metaloproteinases
• Fibrinogen
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22.2 Integrin-containing junctions connect cells to the substratum
Figure 22-9
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22.3 Collagen: the fibrous proteins of the matrix
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22.3 The basic structural unit of collagen is a triple helix
Figure 22-11
Collagen fibrils form by lateral interactions of triple helices
Gly-Pro-XGlycine (R=H)Proline
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22.3 The side-by-side interactions of collagen helices are stabilized by covalent bonds
Figure 22-12
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22.3 Assembly of collagen fibers begins in the ER and is completed outside the cell
Figure 22-14
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22.3 Mutations in collagen reveal aspects of its structure and biosynthesis
Figure 22-15
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22.3 Collagens form diverse structures
Figure 22-16
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22.4 Fibronectins bind many cells to fibrous collagens and other matrix components