Regulation of calcium signals in the nucleus by a nucleoplasmic reticulum
Regulation of calcium signals in the nucleus by a nucleoplasmic reticulum
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DOI：
10.1038/ncb980
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发表时间：
2003-05-01
影响因子：
21.3
通讯作者：
Nathanson, MH
中科院分区：
文献类型：
--
作者：
Echevarria, W;Leite, MF;Nathanson, MH
钙是几乎所有细胞和组织中的第二信使(1)。细胞核内钙信号对基因转录和细胞生长的影响不同于胞质内钙信号；然而，核钙信号是如何调控的尚不清楚。在这里，我们确定了一个网状的核钙储存网络，是连续的内质网和核膜。该网络表达肌醇1,4,5-三磷酸（InsP(3)）受体，并且InsP(3)介导的钙信号的核成分从其局部开始。用少量的InsP(3)刺激这些受体，会在细胞核的这一区域产生少量的钙信号。细胞核中钙的局部释放导致核蛋白激酶C （PKC）易位到核膜区域，而细胞质中钙的释放诱导胞质PKC易位到质膜。我们的研究结果表明，细胞核中含有一个核质网，具有调节局部亚核区域钙信号的能力。这种机制的存在提供了一种潜在的机制，通过这种机制，钙可以同时调节细胞核中许多独立的过程。
Calcium is a second messenger in virtually all cells and tissues(1). Calcium signals in the nucleus have effects on gene transcription and cell growth that are distinct from those of cytosolic calcium signals; however, it is unknown how nuclear calcium signals are regulated. Here we identify a reticular network of nuclear calcium stores that is continuous with the endoplasmic reticulum and the nuclear envelope. This network expresses inositol 1,4,5-trisphosphate (InsP(3)) receptors, and the nuclear component of InsP(3)-mediated calcium signals begins in its locality. Stimulation of these receptors with a little InsP(3) results in small calcium signals that are initiated in this region of the nucleus. Localized release of calcium in the nucleus causes nuclear protein kinase C (PKC) to translocate to the region of the nuclear envelope, whereas release of calcium in the cytosol induces translocation of cytosolic PKC to the plasma membrane. Our findings show that the nucleus contains a nucleoplasmic reticulum with the capacity to regulate calcium signals in localized subnuclear regions. The presence of such machinery provides a potential mechanism by which calcium can simultaneously regulate many independent processes in the nucleus.