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The quantified cell.

Flamholz A, Phillips R, Milo R - Mol. Biol. Cell (2014)

Bottom Line: The microscopic world of a cell can be as alien to our human-centered intuition as the confinement of quarks within protons or the event horizon of a black hole.We are prone to thinking by analogy-Golgi cisternae stack like pancakes, red blood cells look like donuts-but very little in our human experience is truly comparable to the immensely crowded, membrane-subdivided interior of a eukaryotic cell or the intricately layered structures of a mammalian tissue.So in our daily efforts to understand how cells work, we are faced with a challenge: how do we develop intuition that works at the microscopic scale?

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720.

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Back-of-the-envelope calculation of the ATP demand for motility of a cell. Actin filaments criss-cross the leading edge of a motile keratocyte, and their dynamic polymerization results in a net forward motion with a speed of 0.2 μm/s. (Electron micrographs adapted from Svitkina et al., 1997.)
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Figure 2: Back-of-the-envelope calculation of the ATP demand for motility of a cell. Actin filaments criss-cross the leading edge of a motile keratocyte, and their dynamic polymerization results in a net forward motion with a speed of 0.2 μm/s. (Electron micrographs adapted from Svitkina et al., 1997.)

Mentions: However, how many actin filaments are required to move a cell? As shown in Figure 2, the leading edge of a goldfish keratocyte lamellipodium is ≈20 μm long and contains ∼200 actin filaments/μm of length, or ≈4000 filaments in total (Abraham et al., 1999). If actin polymerizes primarily at the leading edge of the lamellipodium (Pantaloni, 2001), then our keratocyte must burn ≈4000 × 100 = 4 × 105 ATP/s to power its movement (Figure 2).


The quantified cell.

Flamholz A, Phillips R, Milo R - Mol. Biol. Cell (2014)

Back-of-the-envelope calculation of the ATP demand for motility of a cell. Actin filaments criss-cross the leading edge of a motile keratocyte, and their dynamic polymerization results in a net forward motion with a speed of 0.2 μm/s. (Electron micrographs adapted from Svitkina et al., 1997.)
© Copyright Policy - creative-commons
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4230611&req=5

Figure 2: Back-of-the-envelope calculation of the ATP demand for motility of a cell. Actin filaments criss-cross the leading edge of a motile keratocyte, and their dynamic polymerization results in a net forward motion with a speed of 0.2 μm/s. (Electron micrographs adapted from Svitkina et al., 1997.)
Mentions: However, how many actin filaments are required to move a cell? As shown in Figure 2, the leading edge of a goldfish keratocyte lamellipodium is ≈20 μm long and contains ∼200 actin filaments/μm of length, or ≈4000 filaments in total (Abraham et al., 1999). If actin polymerizes primarily at the leading edge of the lamellipodium (Pantaloni, 2001), then our keratocyte must burn ≈4000 × 100 = 4 × 105 ATP/s to power its movement (Figure 2).

Bottom Line: The microscopic world of a cell can be as alien to our human-centered intuition as the confinement of quarks within protons or the event horizon of a black hole.We are prone to thinking by analogy-Golgi cisternae stack like pancakes, red blood cells look like donuts-but very little in our human experience is truly comparable to the immensely crowded, membrane-subdivided interior of a eukaryotic cell or the intricately layered structures of a mammalian tissue.So in our daily efforts to understand how cells work, we are faced with a challenge: how do we develop intuition that works at the microscopic scale?

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720.

Show MeSH