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TRANSCRIPT
The Cytoskeleton
Figure 3.5
Figure 3.1
The Diversity of Cells
MreBactin like
FtsZtubulin like
Crescentinintermediate filament like
FtsZtubulin likein mitochondriaschloroplasts
Fig. 4-22b, p. 98
(b) Fluorescent LM showing microtubules in green. Amicrotubule-organizing center (pink dot) is visible besideor over most of the cell nuclei (blue).
50 μm
MT axonémicos MT citoplásmicos
Acetilaciones de las tubulinas estabilizan los MT
ColchicineNocadozole
Vinblastine Vincristine
TaxolPaclitaxel
Centrioles
Centrioles
Fig. 4-24b, p. 99
(b) Note the 9 x 3 arrangement of microtubules.The centriole on the right has been cut transversely.
Centrioles and Cilia
Figure 3.6
+ -
Tau en las neuritas y axones
Neurofibrillary tangles(tauopathies)
Centrioles and Cilia
Figure 3.6
Cilia
Fig. 4-26b, p. 101
(b) Many bundles of microfilaments (green) are evident in thisfluorescent LM of fibroblasts, cells found in connective tissue.
100 μm
Microfilaments
Citochalasin
Phaloidin
Fiber Shortening• As sarcomeres shorten, muscle pulls together,
producing tension
Figure 10–13
Skeletal Muscle Innervation
Figure 10–10a, b (Navigator)
Figure 10–3
A Thick Filament
Figure 10–7c
Figure 10–11
Intermediate Filaments
Cytokeratin
Vimentin (mesenchymal)
NF-H-pind (green) and Glial Fibrillary Acidic Protein (GFAP) (red)
Progeria
Cell Junctions• Anchoring junctions
– Hemidesmosomes- between cells in sheets of tissue – Desmosomes- spot-weld animal cells together
• Adhering junctions- cement cells together formed by cadherins
Superfamilia de immunoglobulinas
N-CAM y L1-CAMRetardación y defectos en cuerpo calloso
Células cancerosas bajan las cantidades de cadherinas.
Desmosomes
Cell recognition
Fibroblasts
Tight Junctions
Attachment to Basal Lamina• Hemidesmosomes
Figure 4–2e
Extracellular Matrix
ECM• Extracellular matrix (ECM)
– Surrounds many animal cell– Carbohydrates and protein
• Fibronectins – glycoproteins of ECM– bind to integrins
• Integrins– receptor proteins in plasma membrane
Proteoglycans Cartilage