Terminal web
The terminal web is a filamentous structure found at the apical surface of epithelial cells that possess microvilli. It is composed primarily of actin filaments stabilized by spectrin, which also anchors the terminal web to the apical cell membrane. The presence of myosin II and tropomyosin helps to explain the contractile ability of the terminal web. When contracted, the terminal web causes a decrease in diameter of the apex of the cell, causing the microvilli, which are anchored into the terminal web through their stiff actin fibers, to spread apart. This spreading apart of the microvilli aids cells in absorption.[1][2][3][4]
References
- ^ Hirokawa N, Tilney LG, Fujiwara K, Heuser JE (1982). "Organization of actin, myosin, and intermediate filaments in the brush border of intestinal epithelial cells". J Cell Biol. 94 (2): 425–43. doi:10.1083/jcb.94.2.425. PMC 2112874. PMID 7202010. link
- ^ Keller TC 3rd, Mooseker MS (1982). "Ca++-calmodulin-dependent phosphorylation of myosin, and its role in brush border contraction in vitro". J Cell Biol. 95 (3): 943–59. doi:10.1083/jcb.95.3.943. PMC 2112925. PMID 6897550. link
- ^ Keller TC 3rd, Conzelman KA, Chasan R, Mooseker MS (1985). "Role of myosin in terminal web contraction in isolated intestinal epithelial brush borders". J Cell Biol. 100 (5): 1647–55. doi:10.1083/jcb.100.5.1647. PMC 2113869. PMID 3988804. link
- ^ Ross, Michael H., and Wojciech Pawlina. "Chapter 5: Epithelial Tissue." Histology: a Text and Atlas : with Correlated Cell and Molecular Biology. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health, 2011. 110. Print.
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