Distinct RanBP1 nuclear export and cargo dissociation mechanisms between fungi and animals
- West China Hospital, Sichuan University, China
- West China Second University Hospital, Sichuan University, China
Abstract
Ran binding protein 1 (RanBP1) is a cytoplasmic-enriched and nuclear-cytoplasmic shuttling protein, playing important roles in nuclear transport. Much of what we know about RanBP1 is learned from fungi. Intrigued by the long-standing paradox of harbouring an extra NES in animal RanBP1, we discovered utterly unexpected cargo dissociation and nuclear export mechanisms for animal RanBP1. In contrast to CRM1-RanGTP sequestration mechanism of cargo dissociation in fungi, animal RanBP1 solely sequestered RanGTP from nuclear export complexes. In fungi, RanBP1, CRM1 and RanGTP formed a 1:1:1 nuclear export complex; in contrast, animal RanBP1, CRM1 and RanGTP formed a 1:1:2 nuclear export complex. The key feature for the two mechanistic changes from fungi to animals was the loss of affinity between RanBP1-RanGTP and CRM1, since residues mediating their interaction in fungi were not conserved in animals. The biological significances of these different mechanisms in fungi and animals were also studied.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Natural Science Foundation of China (80502629)
- Qingxiang Sun
National Natural Science Foundation of China (31671477)
- Da Jia
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Karsten Weis, ETH Zurich, Switzerland
Version history
- Received: August 22, 2018
- Accepted: April 24, 2019
- Accepted Manuscript published: April 25, 2019 (version 1)
- Version of Record published: May 17, 2019 (version 2)
Copyright
© 2019, Li et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Distinct RanBP1 nuclear export and cargo dissociation mechanisms between fungi and animals
eLife 8:e41331.
https://doi.org/10.7554/eLife.41331
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