Terminal web explained

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]}

Notes and References

1. Hirokawa N, Tilney LG, Fujiwara K, Heuser JE . Organization of actin, myosin, and intermediate filaments in the brush border of intestinal epithelial cells. . J Cell Biol . 94 . 2 . 425–43 . 1982 . 7202010 . 10.1083/jcb.94.2.425 . 2112874. link
2. Keller TC 3rd, Mooseker MS . Ca++-calmodulin-dependent phosphorylation of myosin, and its role in brush border contraction in vitro. . J Cell Biol . 95 . 3 . 943–59 . 1982 . 6897550 . 10.1083/jcb.95.3.943 . 2112925. link
3. Keller TC 3rd, Conzelman KA, Chasan R, Mooseker MS . Role of myosin in terminal web contraction in isolated intestinal epithelial brush borders. . J Cell Biol . 100 . 5 . 1647–55 . 1985 . 3988804 . 10.1083/jcb.100.5.1647 . 2113869. link
4. 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.