Braiman A, Priel Z
Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 635, Beer-Sheeva 84105, Israel.
Cell Calcium. 2001 Dec;30(6):361-71. doi: 10.1054/ceca.2001.0245.
A stable localized region of high calcium concentration near the plasma membrane has been postulated to exist as an outcome of prolonged calcium influx and to play a crucial role in regulation of cellular life. However, the mechanism supporting this phenomenon is a perplexing problem. We show here that a sustained localized region of high cytosolic Ca(2+) concentration is formed near the plasma membrane. Calcium influx, calcium uptake by intracellular stores and calcium release from the stores are essential for this phenomenon. Our results strongly suggest that the mechanism of formation of stable calcium gradient near the plasma membrane involves a process of active redistribution-uptake of entering calcium into intracellular stores and its release from the stores toward the plasma membrane.
据推测,由于长时间的钙内流,质膜附近会存在一个稳定的高钙浓度局部区域,并且该区域在细胞生命调节中起着关键作用。然而,支持这一现象的机制是一个令人困惑的问题。我们在此表明,在质膜附近形成了一个持续存在的高胞质Ca(2+)浓度局部区域。钙内流、细胞内储存库对钙的摄取以及储存库中钙的释放对于这一现象至关重要。我们的结果有力地表明,质膜附近稳定钙梯度的形成机制涉及一个主动重新分配的过程,即将进入的钙摄取到细胞内储存库中,并使其从储存库释放到质膜。