ICAD/DFF regulator of apoptotic nuclease is nuclear.
ICAD/DFF regulator of apoptotic nuclease is nuclear.
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凋亡核酸酶的 ICAD/DFF 调节剂是核。
DOI：
10.1006/excr.1998.4212
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发表时间：
1998
影响因子：
3.7
通讯作者：
Earnshaw,WC
中科院分区：
文献类型：
--
作者：
Samejima,K;Earnshaw,WC
在非凋亡细胞中，半胱天冬酶激活的DNA酶CAD/CPAN与一个调节亚基ICAD/DFF相关，ICAD/DFF与其结合并阻断其酶活性。已经提出ICAD的主要功能是抑制健康细胞中细胞质中的CAD。这里提出的实验表明，而不是细胞质，GFP-ICAD融合蛋白是在健康的人，猪，鸡细胞的核。此外，免疫印迹使用抗体鼠ICAD确认存在内源性ICAD和标记蛋白DNA拓扑异构酶I在人的细胞核中，而微管蛋白被发现只在胞质组分。由于ICAD位于细胞核中，因此该蛋白不太可能主要在细胞质中作为CAD/CPAN的锚或作为在半胱天冬酶切割后进入细胞核以激活驻留核酸内切酶的因子起作用。
In nonapoptotic cells, the caspase-activated DNase CAD/CPAN is associated with a regulatory subunit, ICAD/DFF, that binds to it and blocks its enzymatic activity. It has been proposed that a major function of ICAD is to restrain CAD in the cytoplasm in healthy cells. The experiments presented here demonstrate that rather than being cytoplasmic, a GFP–ICAD fusion protein is nuclear in healthy human, pig, and chicken cells. Furthermore, immunoblots using antibodies to murine ICAD confirm the presence of endogenous ICAD and the marker protein DNA topoisomerase I in human nuclei, while tubulin was found solely in the cytosolic fraction. Since ICAD is located in cell nuclei, it is unlikely that the protein functions primarily in the cytoplasm either as an anchor for CAD/CPAN or as a factor that enters the nucleus following caspase cleavage in order to activate resident endonucleases.