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.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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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.
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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