cGMP-dependent protein kinase I gamma encodes a nuclear localization signal that regulates nuclear compartmentation and function.
cGMP-dependent protein kinase I gamma encodes a nuclear localization signal that regulates nuclear compartmentation and function.
复制标题
cGMP 依赖性蛋白激酶 I gamma 编码调节核区室和功能的核定位信号。
DOI：
10.1016/j.cellsig.2014.08.004
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发表时间：
2014
影响因子：
4.8
通讯作者：
RobertsJr,JesseD
中科院分区：
文献类型：
--
作者：
Chen,Jingsi;RobertsJr,JesseD
环鸟苷酸依赖性蛋白激酶I（PKGI）在调节环鸟苷酸如何指定血管平滑肌细胞（SMC）表型方面发挥着重要作用。虽然研究表明PKGI核定位控制cGMP如何调节SMC中的基因表达，但有关调节PKGI核区室化的机制及其在直接调节细胞表型中的作用的信息有限。在这里，我们描述了PKGIγ中的核定位信号序列（NLS），PKGI γ是一种蛋白水解切割的PKGI激酶片段，可转位至SMC的核。使用表达天然和NLS突变体PKGIγ的细胞并用小分子核转运抑制剂处理的免疫定位研究表明，PKGIγ编码组成型活性NLS，其需要输入素α和β来调节其区室化。此外，利用基因编码的核磷酸化CREB生物传感器探针和荧光寿命成像显微镜的研究表明，该NLS控制PKGIγ核功能。此外，尽管观察到细胞溶质PKGIγ活性刺激SMC中MAPK/ERK介导的核CREB信号传导，但确定单独NLS介导的PKGIγ核活性增加这些细胞中分化标记蛋白的表达。这些结果表明，NLS介导的核PKGIγ定位在PKGI如何调节血管SMC表型中起重要作用。
cGMP-dependent protein kinase I (PKGI) plays an important role in regulating how cGMP specifies vascular smooth muscle cell (SMC) phenotype. Although studies indicate that PKGI nuclear localization controls how cGMP regulates gene expression in SMC, information about the mechanisms that regulate PKGI nuclear compartmentation and its role in directly regulating cell phenotype is limited. Here we characterize a nuclear localization signal sequence (NLS) in PKGIγ, a proteolytically cleaved PKGI kinase fragment that translocates to the nucleus of SMC. Immuno-localization studies using cells expressing native and NLS-mutant PKGIγ, and treated with a small molecule nuclear transport inhibitor, indicated that PKGIγ encodes a constitutively active NLS that requires importin α and β for regulation of its compartmentation. Moreover, studies utilizing a genetically encoded nuclear phospho-CREB biosensor probe and fluorescence lifetime imaging microscopy demonstrated that this NLS controls PKGIγ nuclear function. In addition, although cytosolic PKGIγ-activity was observed to stimulate MAPK/ERK-mediated nuclear CREB signaling in SMC, NLS-mediated PKGIγ nuclear activity alone was determined to increase the expression of differentiation marker proteins in these cells. These results indicate that NLS-mediated nuclear PKGIγ localization plays an important role in how PKGI regulates vascular SMC phenotype.