Department of Zoology and Animal Biology, University of Geneva, quai Ernest-Ansermet 30, CH-1211 Geneva 4, Switzerland.
Nucleic Acids Res. 2010 Jul;38(13):4254-62. doi: 10.1093/nar/gkq168. Epub 2010 Mar 18.
In Drosophila, SU(VAR)3-7 is an essential heterochromatin component. It is required for proper chromatin condensation, and changing its dose modifies position-effect variegation. Sumoylation is a post-translational modification shown to play a role in diverse biological processes. Here, we demonstrate that sumoylation is essential for proper heterochromatin function in Drosophila through modification of SU(VAR)3-7. Indeed, SU(VAR)3-7 is sumoylated at lysine K839; this modification is required for localization of SU(VAR)3-7 at pericentric heterochromatin, chromosome 4, and telomeres. In addition, sumoylation of SU(VAR)3-7 is a prerequisite for its ability to enhance position-effect variegation. Thus, these results show that the heterochromatic function of SU(VAR)3-7 depends on its own sumoylation, and unveil a role for sumoylation in Drosophila heterochromatin.
在果蝇中，SU(VAR)3-7 是一种必需的异染色质成分。它对于适当的染色质凝聚是必需的，并且改变其剂量会改变位置效应的斑驳现象。SUMO 化是一种已被证明在多种生物学过程中发挥作用的翻译后修饰。在这里，我们通过 SU(VAR)3-7 的修饰证明 SUMO 化对于果蝇中适当的异染色质功能是必需的。事实上，SU(VAR)3-7 在赖氨酸 K839 处被 SUMO 化；这种修饰对于 SU(VAR)3-7 在着丝粒异染色质、染色体 4 和端粒处的定位是必需的。此外，SU(VAR)3-7 的 SUMO 化是其增强位置效应斑驳现象能力的前提。因此，这些结果表明 SU(VAR)3-7 的异染色质功能取决于其自身的 SUMO 化，并揭示了 SUMO 化在果蝇异染色质中的作用。
