Internuclear exchange of an inner nuclear membrane protein (p55) in heterokaryons: in vivo evidence for the interaction of p55 with the nuclear lamina
Internuclear exchange of an inner nuclear membrane protein (p55) in heterokaryons: in vivo evidence for the interaction of p55 with the nuclear lamina
复制标题
异核体中内核膜蛋白 (p55) 的核间交换：p55 与核纤层相互作用的体内证据
作者：
Lisa Powell;Brian Burke
已在大鼠/小鼠和大鼠/仓鼠异核体中研究了内核膜的整合蛋白在核之间的运动。这种蛋白质，p55，被发现在一段时间内约6小时的新的蛋白质合成的情况下，细胞核之间的平衡。当使用未分化的鼠胚胎癌（P19）（其缺乏核纤层蛋白A和C）构建大鼠/小鼠异核体时，未观察到p55在小鼠细胞核中的积累。然而，P19细胞核可以通过在细胞融合前用人核纤层蛋白A分离亲本细胞来使其有能力积累p55，这支持了p55可能与核纤层相互作用的观点。由于p55似乎不能从核膜上解离，因此可以得出结论，核之间的这种交换不会发生在水相中，而是可能是膜介导的。有人建议，这种蛋白质可以自由移动的内部和外部核膜之间通过连续性在核孔复合物和核之间的转移发生通过横向扩散通过外周ER，这似乎形成一个单一的连续膜系统，在这些异核体。这些观察结果的一个含义是，至少一些整合蛋白在内核膜中的积累可能是通过与其他核组分的相互作用介导的，并且可能不需要单个定义的靶向序列。
The movement between nuclei of an integral protein of the inner nuclear membrane has been studied in rat/mouse and rat/hamster heterokaryons. This protein, p55, was found to equilibrate between nuclei over a period of approximately 6 h in the absence of new protein synthesis. When rat/mouse heterokaryons were constructed using an undifferentiated murine embryonal carcinoma (P19), which lacks lamins A and C, no accumulation of p55 in the mouse cell nucleus was observed. However, P19 nuclei could be rendered competent to accumulate p55 by transfecting the parent cells with human lamin A before cell fusion, supporting the notion that p55 may interact with the nuclear lamina. Since p55 does not appear to be able to dissociate from the nuclear membrane, it is concluded that this exchange between nuclei does not occur in the aqueous phase and instead is probably membrane mediated. It is proposed that this protein may be free to move between the inner and outer nuclear membranes via the continuities at the nuclear pore complexes and that transfer between nuclei occurs via lateral diffusion through the peripheral ER, which appears to form a single continuous membrane system in these heterokaryons. One implication of these observations is that accumulation of at least some integral proteins in the inner nuclear membrane may be mediated by interactions with other nuclear components and may not require a single defined targeting sequence.
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大鼠肝核纤层蛋白多肽家族的其他成员。
DOI：
--
发表时间：
1989
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Kaufmann,SH
通讯作者：
Kaufmann,SH
细胞核：结构、功能和动力学。
影响因子：
16.6
作者：
Newport,JW;Forbes,DJ
通讯作者：
Forbes,DJ
核膜中的核纤层蛋白 B 受体。
DOI：
10.1073/pnas.85.22.8531
发表时间：
1988
影响因子：
11.1
作者：
Worman,HJ;Yuan,J;Blobel,G;Georgatos,SD
通讯作者：
Georgatos,SD
DOI：
10.1042/bj2410039
发表时间：
1987
期刊：
The Biochemical journal
影响因子：
--
作者：
C. Kaetzel;C. K. Rao;M. Lamm
通讯作者：
C. Kaetzel;C. K. Rao;M. Lamm