Critical Concentration
What determines whether the ends grow or shrink is entirely dependent on the cytosolic concentration of available monomer subunits in the surrounding area. Both the plus and the minus ends have a different critical concentration (CC). Examples in which the cytosolic concentration can affect the critical concentrations are as followed:
- A cytosolic concentration of subunits above both the CC+ and CC– ends results in subunit addition at both ends
- A cytosolic concentration of subunits below both the CC+ and CC– ends results in subunit removal at both ends
Both the plus and minus ends have different CC values and generally, the plus end will always have a lower CC value than the minus end. This is due to the increased ease of subunit addition to the plus end, leading to faster growth.
Note that the cytosolic concentration of the monomer subunit between the CC+ and CC– ends is what is defined as treadmilling in which there is growth at the plus end, and shrinking on the minus end.
Read more about this topic: Treadmilling, Detailed Process
Famous quotes containing the word critical:
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