Mispositioned nuclei are a hallmark of skeletal muscle disease. Many of the genes that are linked to Emery-Dreifuss muscular dystrophy (EDMD) encode proteins that are critical for nuclear movement in various cells, suggesting that disruptions in nuclear movement and position may contribute to disease progression. However, how these genes are coordinated to move nuclei is not known. Here, we focussed on two different emerin proteins in Drosophila, Bocksbeutel and Otefin, and their effects on nuclear movement. Although nuclear position was dependent on both, elimination of either Bocksbeutel or Otefin produced distinct phenotypes that were based in differential effects on the KASH-domain protein Klarsicht. Specifically, loss of Bocksbeutel reduced Klarsicht localization to the nucleus and resulted in a disruption in nuclear separation. Loss of Otefin increased the transcription of Klarsicht and led to premature separation of nuclei and their positioning closer to the edge of the muscle. Consistent with opposing functions, nuclear position is normal in otefin; bocksbeutel double mutants. These data indicate emerin-dependent regulation of Klarsicht levels in the nuclear envelope is a critical determinant of nuclear position.

中文翻译：

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果蝇Emerins控制LINC复合体的定位和转录以调节肌核位置。

核位置不正确是骨骼肌疾病的标志。与金刚砂-Dreifuss肌营养不良症（EDMD）相关的许多基因编码的蛋白质对于各种细胞的核运动至关重要，这表明核运动和位置的破坏可能有助于疾病的进展。但是，如何协调这些基因移动核尚不清楚。在这里，我们专注于果蝇中的两种不同的Emerin蛋白，Bocksbeutel和Otefin，及其对核运动的影响。尽管核位置都依赖于两者，但是消除Bocksbeutel或Otefin会产生不同的表型，这是基于对KASH域蛋白Klarsicht的不同影响。具体而言，Bocksbeutel的丢失减少了克拉西克特在细胞核中的定位，并导致了核分离的中断。Otefin的丢失会增加Klarsicht的转录，并导致核的过早分离以及它们靠近肌肉边缘的定位。与相反的功能一致，otefin的核位置是正常的；bocksbeutel双突变体。这些数据表明，核包膜中克拉霉素水平的依赖于神经磷酸的调节是决定核位置的关键。