Difference in nucleocytoplasmic shuttling sequences of rat and human constitutive active/androstane receptor
Difference in nucleocytoplasmic shuttling sequences of rat and human constitutive active/androstane receptor
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DOI：
10.1016/j.bbamcr.2007.03.020
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发表时间：
2007-06-01
影响因子：
5.1
通讯作者：
Inouye, Yoshio
中科院分区：
文献类型：
--
作者：
Kanno, Yuichiro;Suzuki, Motoyoshi;Inouye, Yoshio
在自发多核细胞中的光漂白后荧光恢复（FRAP）表明，大鼠和人组成性活性/雄烷受体（汽车）都是具有核定位信号（NLS）和核输出信号（NES）的穿梭蛋白。我们先前在大鼠CAR中鉴定了两个NLS：铰链区中的NLS 1（残基100-108）和配体结合结构域中的NLS 2（残基111-320）。在本研究中，我们比较了大鼠和人汽车之间的细胞内定位信号。它们在COS-7细胞中的细胞内定位存在显著差异，因为与大鼠CAR不同，人CAR由于位置106处的氨基酸变化而不含NLS 1。在先前在大鼠CAR的配体结合结构域（残基220-258）内鉴定的细胞质保留区中发现了对来普霉素B的抑制作用敏感的CRM 1依赖性富亮氨酸内斯。我们发现人CAR在残基170和220之间的配体结合结构域中具有内斯。此外，我们在大鼠和人汽车的残基317-358之间检测到CRM 1非依赖性C末端NES。通过N端截短去除NLS 1和异种化学反应信号的突变导致大鼠CAR定位于COS-7细胞的细胞质中，我们怀疑这是由于NLS 2的掩蔽。(c)2007 Elsevier B.V保留所有权利。
Fluorescence recovery after photobleaching (FRAP) in spontaneous multinuclear cells shows that both rat and human constitutive active/ androstane receptors (CARs) are shuttling proteins with both nuclear localization signals (NLSs) and nuclear export signals (NESs). We previously identified two NLSs in rat CAR: NLS1 in the hinge region (residues 100-108) and NLS2 in the ligand-binding domain (residues 111-320). In the present study, we compared the intracellular localization signals between rat and human CARs. There was a marked difference in their intracellular localization in COS-7 cells because, unlike rat CAR, human CAR does not contain NLS1 due to an amino acid change at position 106. A CRM1-dependent leucine-rich NES, which is sensitive to an inhibitory effect of leptomycin B, was found in the cytoplasmic retention region previously identified within the ligand-binding domain of rat CAR (residues 220-258). We found that human CAR instead has a NES in the ligand-binding domain between residues 170 and 220. Also, we detected CRM1 -independent C-terminal NESs between residues 317-358 of rat and human CARs. Removal of NLS1 by N-terminal truncation and mutation of xenochemical response signal caused rat CAR to localize in the cytoplasm of COS-7 cells, which we suspect is due to the masking of NLS2. (c) 2007 Elsevier B.V All rights reserved.