Rxivist logo

ESCRT recruitment by the inner nuclear membrane protein Heh1 is regulated by Hub1-mediated alternative splicing

By Matias Capella, Lucia Martin Caballero, Boris Pfander, Sigurd Braun, Stefan Jentsch

Posted 26 Jun 2020
bioRxiv DOI: 10.1101/2020.06.25.171694

Misassembled nuclear pore complexes (NPCs) are removed by sealing off the surrounding nuclear envelope (NE), which is mediated by members of the ESCRT (endosomal sorting complexes required for transport) machinery. Recruitment of ESCRT proteins to the NE is mediated by the interaction between the ESCRT member Chm7 and the inner nuclear membrane protein Heh1, which belongs to the conserved LEM family. Increased ESCRT recruitment results in excessive membrane scission at damage sites but its regulation remains poorly understood. Here, we show that Hub1-mediated alternative splicing of HEH1 pre-mRNA, resulting into its shorter form Heh1-S, is critical for the integrity of the NE. ESCRT-III mutants lacking Hub1 or Heh1-S display severe growth defects and accumulate improperly assembled NPCs. This depends on the interaction of Chm7 with the conserved MSC domain only present in the longer spliced variant Heh1-L. Heh1 variants assemble into heterodimers and we demonstrate that a unique splice segment in Heh1-S suppresses growth defects associated with uncontrolled interaction between Heh1-L and Chm7. Together, our findings reveal that Hub1-mediated splicing generates Heh1-S to regulate ESCRT recruitment to the nuclear envelope.

Download data

  • Downloaded 378 times
  • Download rankings, all-time:
    • Site-wide: 131,300
    • In cell biology: 5,923
  • Year to date:
    • Site-wide: 172,947
  • Since beginning of last month:
    • Site-wide: 173,130

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide