Lebart Marie-Christine, Benyamin Yves
UMR5539, EPHE-CNRS-UM2, cc107, Université de Montpellier II, France.
FEBS J. 2006 Aug;273(15):3415-26. doi: 10.1111/j.1742-4658.2006.05350.x.
Cells offer different types of cytoskeletal anchorages: transitory structures such as focal contacts and perennial ones such as the sarcomeric cytoskeleton of muscle cells. The turnover of these structures is controlled with different timing by a family of cysteine proteases activated by calcium, the calpains. The large number of potential substrates present in each of these structures imposes fine tuning of the activity of the proteases to avoid excessive action. This phenomenon is thus guaranteed by various types of regulation, ranging from a relatively high calcium concentration necessary for activation, phosphorylation of substrates or the proteases themselves with either a favorable or inhibitory effect, possible intervention of phospholipids, and the presence of a specific inhibitor and its possible degradation before activation. Finally, formation of multiprotein complexes containing calpains offers a new method of regulation.
诸如粘着斑等临时性结构以及诸如肌肉细胞的肌节细胞骨架等永久性结构。这些结构的周转由一类由钙激活的半胱氨酸蛋白酶——钙蛋白酶，在不同的时间进行控制。这些结构中的每一个都存在大量潜在底物，这就要求对蛋白酶的活性进行微调，以避免过度作用。因此，这种现象通过各种类型的调节得以保证，从激活所需的相对较高的钙浓度、底物或蛋白酶本身的磷酸化（具有有利或抑制作用）、磷脂的可能干预，到特定抑制剂的存在及其在激活前可能的降解。最后，含有钙蛋白酶的多蛋白复合物的形成提供了一种新的调节方法。
