A selective block of nuclear actin export stabilizes the giant nuclei of Xenopus oocytes

  title={A selective block of nuclear actin export stabilizes the giant nuclei of Xenopus oocytes},
  author={Markus T. Bohnsack and Theis St{\"u}ven and Christa Kuhn and Volker C. Cordes and Dirk G{\"o}rlich},
  journal={Nature Cell Biology},
Actin is a major cytoskeletal element and is normally kept cytoplasmic by exportin 6 (Exp6)-driven nuclear export. Here, we show that Exp6 recognizes actin features that are conserved from yeast to human. Surprisingly however, microinjected actin was not exported from Xenopus laevis oocyte nuclei, unless Exp6 was co-injected, indicating that the pathway is inactive in this cell type. Indeed, Exp6 is undetectable in oocytes, but is synthesized from meiotic maturation onwards, which explains how… 

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