Changes in nuclear morphology are observed in diverse developmental processes as well as in pathological conditions. Modification of nuclear membrane and nuclear lamina protein levels results in altered nuclear shapes, as it has been demonstrated in experimental systems ranging from yeast to human cells. The important role of nuclear membrane components in regulating nuclear morphology is additionally highlighted by the abnormally shaped nuclei observed in diseases where nuclear lamina proteins are mutated. Even though the effect of nuclear envelope components on nuclear shape has been thoroughly described, not much is known about the molecular mechanisms that govern these events. In addition to the known role of intermediate filament formation by lamins, here we discuss several mechanisms that might alone or in combination participate in the regulation of nuclear shape observed upon modification of the levels of nuclear membrane and lamina proteins. Based on recent work with the two farnesylated nuclear membrane Drosophila proteins, kugelkern and lamin Dm0, we propose that the direct interaction of farnesylated nuclear membrane proteins with the phospholipid bilayer leads to nuclear envelope deformation. In addition to this mechanism, we suggest that the interaction of nuclear membrane and lamina proteins with cytoskeletal elements and chromatin, and modifications in lipid biosynthesis might also be involved in the formation of abnormally shaped nuclei.

中文翻译：

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确定核形状：法尼基化核膜蛋白的作用


在不同的发育过程以及病理条件下观察到核形态的变化。核膜和核纤层蛋白水平的改变会导致核形状的改变，这一点已在从酵母到人类细胞的实验系统中得到证实。在核纤层蛋白突变的疾病中观察到的异常形状的细胞核进一步强调了核膜成分在调节核形态中的重要作用。尽管核膜成分对核形状的影响已被彻底描述，但人们对控制这些事件的分子机制知之甚少。除了核纤层蛋白形成中间丝的已知作用之外，在这里我们讨论了几种可能单独或组合参与核膜和核纤层蛋白水平修饰时观察到的核形状调节的机制。基于最近对两种法尼基化核膜果蝇蛋白 kugelkern 和核纤层蛋白 Dm0 的研究，我们提出法尼基化核膜蛋白与磷脂双层的直接相互作用导致核膜变形。除了这种机制之外，我们认为核膜和核纤层蛋白与细胞骨架元件和染色质的相互作用以及脂质生物合成的修饰也可能参与异常形状的细胞核的形成。