Entry into the nuclear pore complex is controlled by a cytoplasmic exclusion zone containing dynamic GLFG-repeat nucleoporin domains

Fiserova, J.; Spink, M.; Richards, S.A.; Saunter, C.; Goldberg, M.W.

doi:10.1242/jcs.133272

Entry into the nuclear pore complex is controlled by a cytoplasmic exclusion zone containing dynamic GLFG-repeat nucleoporin domains

Fiserova, J.; Spink, M.; Richards, S.A.; Saunter, C.; Goldberg, M.W.

Authors

J. Fiserova

M. Spink

S.A. Richards

C. Saunter

Professor Martin Goldberg m.w.goldberg@durham.ac.uk
Professor

Abstract

Nuclear pore complexes (NPCs) mediate nucleocytoplasmic movement. The central channel contains proteins with phenylalanine-glycine (FG) repeats, or variations (GLFG, glycine-leucine-phenylalanine-glycine). These are ‘intrinsically disordered’ and often represent weak interaction sites that become ordered upon interaction. We investigated this possibility during nuclear transport. Using electron microscopy of S. cerevisiae, we show that NPC cytoplasmic filaments form a dome-shaped structure enclosing GLFG domains. GLFG domains extend out of this structure and are part of an ‘exclusion zone’ that might act as a partial barrier to entry of transport-inert proteins. The anchor domain of a GLFG nucleoporin locates exclusively to the central channel. By contrast, the localisation of the GLFG domains varied between NPCs and could be cytoplasmic, central or nucleoplasmic and could stretch up to 80 nm. These results suggest a dynamic exchange between ordered and disordered states. In contrast to diffusion through the NPC, transport cargoes passed through the exclusion zone and accumulated near the central plane. We also show that movement of cargo through the NPC is accompanied by relocation of GLFG domains, suggesting that binding, restructuring and movement of these domains could be part of the translocation mechanism.

Citation

Fiserova, J., Spink, M., Richards, S., Saunter, C., & Goldberg, M. (2014). Entry into the nuclear pore complex is controlled by a cytoplasmic exclusion zone containing dynamic GLFG-repeat nucleoporin domains. Journal of Cell Science, 127, 124-136. https://doi.org/10.1242/jcs.133272

Journal Article Type	Article
Acceptance Date	Sep 29, 2013
Online Publication Date	Jan 1, 2014
Publication Date	Jan 1, 2014
Deposit Date	Oct 1, 2013
Publicly Available Date	Aug 22, 2014
Journal	Journal of Cell Science
Print ISSN	0021-9533
Electronic ISSN	1477-9137
Publisher	The Company of Biologists
Peer Reviewed	Peer Reviewed
Volume	127
Pages	124-136
DOI	https://doi.org/10.1242/jcs.133272
Keywords	Nuclear pore, Transport, Phenylalanine-glycine repeat, GLFG.