Division of Endocrinology and Metabolism and Lipids, Department of Medicine, Emory University School of Medicine, 101 Woodruff Circle, 1305 WMRB, Atlanta, GA 30322-0001, USA.
Mol Cell Biochem. 2011 Jul;353(1-2):101-37. doi: 10.1007/s11010-011-0779-4. Epub 2011 Mar 24.
Regucalcin was discovered in 1978 as a calcium-binding protein that does not contain EF-hand motif of calcium-binding domain (Yamaguchi and Yamamoto Chem Pharm Bull 26:1915-1918, 1978). The name regucalcin was proposed for this calcium-binding protein, which can regulate various Ca(2+)-dependent enzyme activations in liver cells. The regucalcin gene is localized on the chromosome X, and the organization of the regucalcin gene consists of seven exons and six introns. AP-1, NF1-A1, and RGPR-p117 bind to the promoter region of the rat regucalcin gene and enhance transcription activity of regucalcin gene expression that is mediated through calcium signaling. Regucalcin plays a pivotal role in the keep of intracellular calcium ion (Ca(2+)) homeostasis due to activating Ca(2+) pump enzymes in the plasma membrane (basolateral membrane), microsomes (endoplasmic reticulum), mitochondria, and nuclei of many cell types. Regucalcin has a suppressive effect on calcium signaling from the cytoplasm to the nucleus in the proliferative cells. Regucalcin has also been demonstrated to transport to the nucleus, and it can inhibit Ca(2+)-dependent protein kinase and protein phosphatase activities, Ca(2+)-activated deoxyribonucleic acid (DNA) fragmentation, and DNA and ribonucleic acid (RNA) synthesis in the nucleus. Overexpression of regucalcin suppresses cell death and apoptosis in the cloned rat hepatoma cells induced by various signaling factors. Regucalcin can inhibit the enhancement of cell proliferation due to hormonal stimulation. Regucalcin plays an important role as a regulatory protein in cell signaling system, and it is proposed to play a pivotal role in keep of cell homeostasis and function.
Regucalcin 于 1978 年被发现，是一种不含钙结合域 EF 手模的钙结合蛋白（Yamaguchi 和 Yamamoto，Chem Pharm Bull 26：1915-1918，1978）。该钙结合蛋白可以调节肝细胞中各种依赖 Ca2+的酶活性，因此被命名为 regucalcin。Regucalcin 基因位于 X 染色体上，其基因组织由 7 个外显子和 6 个内含子组成。AP-1、NF1-A1 和 RGPR-p117 结合到大鼠 regucalcin 基因的启动子区域，增强通过钙信号转导介导的 regucalcin 基因表达的转录活性。Regucalcin 通过激活质膜（基底外侧膜）、微粒体（内质网）、线粒体和许多细胞类型的核中的 Ca2+泵酶，在维持细胞内钙离子（Ca2+）稳态方面发挥关键作用。Regucalcin 对增殖细胞中细胞质到细胞核的钙信号具有抑制作用。Regucalcin 还被证明可以转运到细胞核，并可以抑制 Ca2+依赖性蛋白激酶和蛋白磷酸酶活性、Ca2+激活的脱氧核糖核酸（DNA）片段化以及细胞核中的 DNA 和核糖核酸（RNA）合成。Regucalcin 的过度表达可以抑制各种信号因子诱导的克隆大鼠肝癌细胞的细胞死亡和细胞凋亡。Regucalcin 可以抑制激素刺激引起的细胞增殖增强。Regucalcin 作为细胞信号转导系统中的调节蛋白发挥重要作用，被认为在维持细胞内稳态和功能方面发挥关键作用。
