Correlation Engine 2.0
Clear Search sequence regions

  • cell nucleolus (1)
  • cell nucleus (1)
  • factors (2)
  • filament (2)
  • gene (1)
  • human (2)
  • Mdm1 (6)
  • nexin (5)
  • nucleolar proteins (3)
  • nutrient (2)
  • protein complex (1)
  • protein human (1)
  • regulates (1)
  • rrna gene (1)
  • sirolimus (2)
  • SNX14 (3)
  • TORC1 (7)
  • vacuole (6)
  • yeast (1)
  • Sizes of these terms reflect their relevance to your search.

    The degradation of nucleolar proteins - nucleophagy - is elicited by nutrient starvation or the inactivation of target of rapamycin complex 1 (TORC1) protein kinase in budding yeast. Prior to nucleophagy, nucleolar proteins migrate to the nucleus-vacuole junction (NVJ), where micronucleophagy occurs, whereas rDNA (rRNA gene) repeat regions are condensed and escape towards NVJ-distal sites. This suggests that the NVJ controls nucleolar dynamics from outside of the nucleus after TORC1 inactivation, but its molecular mechanism is unclear. Here, we show that sorting nexin (SNX) Mdm1, an inter-organelle tethering protein at the NVJ, mediates TORC1 inactivation-induced nucleolar dynamics. Furthermore, Mdm1 was required for proper nucleophagic degradation of nucleolar proteins after TORC1 inactivation, where it was dispensable for the induction of nucleophagic flux itself. This indicated that nucleophagy and nucleolar dynamics are independently regulated by TORC1 inactivation. Finally, Mdm1 was critical for survival during nutrient starvation conditions. Mutations of SNX14, a human Mdm1 homolog, cause neurodevelopmental disorders. This study provides a novel insight into relationship between sorting nexin-mediated microautophagy and neurodevelopmental disorders. Copyright © 2021 Elsevier Inc. All rights reserved.


    Tasnuva Sharmin, Tsuneyuki Takuma, Shamsul Morshed, Takashi Ushimaru. Sorting nexin Mdm1/SNX14 regulates nucleolar dynamics at the NVJ after TORC1 inactivation. Biochemical and biophysical research communications. 2021 May 07;552:1-8

    Expand section icon Mesh Tags

    Expand section icon Substances

    PMID: 33740659

    View Full Text